diff --git a/user/src/com/google/gwt/user/cellview/client/AbstractHasData.java b/user/src/com/google/gwt/user/cellview/client/AbstractHasData.java
index 79cf0a4..234e6bd 100644
--- a/user/src/com/google/gwt/user/cellview/client/AbstractHasData.java
+++ b/user/src/com/google/gwt/user/cellview/client/AbstractHasData.java
@@ -28,7 +28,6 @@
 import com.google.gwt.event.shared.HandlerRegistration;
 import com.google.gwt.safehtml.shared.SafeHtml;
 import com.google.gwt.safehtml.shared.SafeHtmlBuilder;
-import com.google.gwt.user.cellview.client.HasDataPresenter.ElementIterator;
 import com.google.gwt.user.cellview.client.HasDataPresenter.LoadingState;
 import com.google.gwt.user.client.DOM;
 import com.google.gwt.user.client.Event;
@@ -75,30 +74,15 @@
       return hasData.addHandler(handler, type);
     }
 
-    public boolean dependsOnSelection() {
-      return hasData.dependsOnSelection();
-    }
-
-    public int getChildCount() {
-      return hasData.getChildCount();
-    }
-
-    public ElementIterator getChildIterator() {
-      return new HasDataPresenter.DefaultElementIterator(this,
-          hasData.getChildContainer().getFirstChildElement());
-    }
-
-    public void onUpdateSelection() {
-      hasData.onUpdateSelection();
-    }
-
     public void render(SafeHtmlBuilder sb, List<T> values, int start,
         SelectionModel<? super T> selectionModel) {
       hasData.renderRowValues(sb, values, start, selectionModel);
     }
 
-    public void replaceAllChildren(List<T> values, SafeHtml html) {
+    public void replaceAllChildren(List<T> values, SafeHtml html,
+        boolean stealFocus) {
       // Removing elements can fire a blur event, which we ignore.
+      hasData.isFocused = hasData.isFocused || stealFocus;
       wasFocused = hasData.isFocused;
       hasData.isRefreshing = true;
       hasData.replaceAllChildren(values, html);
@@ -106,8 +90,10 @@
       fireValueChangeEvent();
     }
 
-    public void replaceChildren(List<T> values, int start, SafeHtml html) {
+    public void replaceChildren(List<T> values, int start, SafeHtml html,
+        boolean stealFocus) {
       // Removing elements can fire a blur event, which we ignore.
+      hasData.isFocused = hasData.isFocused || stealFocus;
       wasFocused = hasData.isFocused;
       hasData.isRefreshing = true;
       hasData.replaceChildren(values, start, html);
@@ -132,6 +118,7 @@
 
     public void setKeyboardSelected(int index, boolean seleted,
         boolean stealFocus) {
+      hasData.isFocused = hasData.isFocused || stealFocus;
       hasData.setKeyboardSelected(index, seleted, stealFocus);
     }
 
@@ -141,10 +128,6 @@
       hasData.isRefreshing = false;
     }
 
-    public void setSelected(Element elem, boolean selected) {
-      hasData.setSelected(elem, selected);
-    }
-
     /**
      * Fire a value change event.
      */
@@ -321,7 +304,7 @@
    */
   public T getDisplayedItem(int indexOnPage) {
     checkRowBounds(indexOnPage);
-    return presenter.getRowData().get(indexOnPage);
+    return presenter.getRowDataValue(indexOnPage);
   }
 
   /**
@@ -330,7 +313,12 @@
    * @return a List of displayed items
    */
   public List<T> getDisplayedItems() {
-    return new ArrayList<T>(presenter.getRowData());
+    List<T> list = new ArrayList<T>();
+    int rowCount = presenter.getRowDataSize();
+    for (int i = 0; i < rowCount; i++) {
+      list.add(presenter.getRowDataValue(i));
+    }
+    return list;
   }
 
   public KeyboardPagingPolicy getKeyboardPagingPolicy() {
@@ -376,6 +364,7 @@
    * @return the {@link Element} that contains the rendered row values
    */
   public Element getRowContainer() {
+    presenter.flush();
     return getChildContainer();
   }
 
@@ -664,7 +653,8 @@
    */
   protected Object getValueKey(T value) {
     ProvidesKey<T> keyProvider = getKeyProvider();
-    return keyProvider == null ? value : keyProvider.getKey(value);
+    return (keyProvider == null || value == null) ? value
+        : keyProvider.getKey(value);
   }
 
   /**
@@ -676,14 +666,13 @@
   protected abstract boolean isKeyboardNavigationSuppressed();
 
   /**
-   * Checks that the row is within the correct bounds.
+   * Checks that the row is within bounds of the view.
    *
    * @param row row index to check
    * @return true if within bounds, false if not
    */
   protected boolean isRowWithinBounds(int row) {
-    return row >= 0 && row < getChildCount()
-        && row < presenter.getRowData().size();
+    return row >= 0 && row < presenter.getRowDataSize();
   }
 
   /**
@@ -714,7 +703,12 @@
 
   /**
    * Called when selection changes.
+   * 
+   * @deprecated this method is never called by AbstractHasData, render the
+   *             selected styles in
+   *             {@link #renderRowValues(SafeHtmlBuilder, List, int, SelectionModel)}
    */
+  @Deprecated
   protected void onUpdateSelection() {
   }
 
@@ -723,7 +717,7 @@
    *
    * @param sb the {@link SafeHtmlBuilder} to render into
    * @param values the row values
-   * @param start the start index of the values
+   * @param start the absolute start index of the values
    * @param selectionModel the {@link SelectionModel}
    */
   protected abstract void renderRowValues(SafeHtmlBuilder sb, List<T> values,
@@ -746,7 +740,7 @@
    * should be appended.
    *
    * @param values the values of the new children
-   * @param start the start index to be replaced
+   * @param start the start index to be replaced, relative to the page start
    * @param html the HTML to convert
    */
   protected void replaceChildren(List<T> values, int start, SafeHtml html) {
@@ -799,8 +793,14 @@
    *
    * @param elem the element to update
    * @param selected true if selected, false if not
+   * @deprecated this method is never called by AbstractHasData, render the
+   *             selected styles in
+   *             {@link #renderRowValues(SafeHtmlBuilder, List, int, SelectionModel)}
    */
-  protected abstract void setSelected(Element elem, boolean selected);
+  @Deprecated
+  protected void setSelected(Element elem, boolean selected) {
+    // Never called.
+  }
 
   /**
    * Add a {@link ValueChangeHandler} that is called when the display values
@@ -815,47 +815,11 @@
     return addHandler(handler, ValueChangeEvent.getType());
   }
 
-  /**
-   * Return the number of child elements.
-   */
-  int getChildCount() {
-    return getChildContainer().getChildCount();
-  }
-
   HasDataPresenter<T> getPresenter() {
     return presenter;
   }
 
   /**
-   * Get the first index of a displayed item according to its key.
-   *
-   * @param value the value
-   * @return the index of the item, or -1 of not found
-   */
-  int indexOf(T value) {
-    ProvidesKey<T> keyProvider = getKeyProvider();
-    List<T> items = getDisplayedItems();
-
-    // If no key provider is present, just compare the objets.
-    if (keyProvider == null) {
-      return items.indexOf(value);
-    }
-
-    // Compare the keys of each object.
-    Object key = keyProvider.getKey(value);
-    if (key == null) {
-      return -1;
-    }
-    int itemCount = items.size();
-    for (int i = 0; i < itemCount; i++) {
-      if (key.equals(keyProvider.getKey(items.get(i)))) {
-        return i;
-      }
-    }
-    return -1;
-  }
-
-  /**
    * Set the current loading state of the data.
    *
    * @param state the loading state
diff --git a/user/src/com/google/gwt/user/cellview/client/CellBasedWidgetImpl.java b/user/src/com/google/gwt/user/cellview/client/CellBasedWidgetImpl.java
index d8dde3a..2e179f8 100644
--- a/user/src/com/google/gwt/user/cellview/client/CellBasedWidgetImpl.java
+++ b/user/src/com/google/gwt/user/cellview/client/CellBasedWidgetImpl.java
@@ -17,10 +17,12 @@
 
 import com.google.gwt.core.client.GWT;
 import com.google.gwt.core.client.Scheduler.ScheduledCommand;
+import com.google.gwt.dom.client.Element;
 import com.google.gwt.safehtml.shared.SafeHtml;
 import com.google.gwt.user.client.Event;
 import com.google.gwt.user.client.ui.Widget;
 
+import java.util.HashSet;
 import java.util.Set;
 
 /**
@@ -45,7 +47,31 @@
     return impl;
   }
 
+  /**
+   * The set of natively focusable elements.
+   */
+  private final Set<String> focusableTypes;
+
   CellBasedWidgetImpl() {
+    focusableTypes = new HashSet<String>();
+    focusableTypes.add("select");
+    focusableTypes.add("input");
+    focusableTypes.add("textarea");
+    focusableTypes.add("option");
+    focusableTypes.add("button");
+    focusableTypes.add("label");
+  }
+
+  /**
+   * Check if an element is focusable. If an element is focusable, the cell
+   * widget should not steal focus from it.
+   * 
+   * @param elem the element
+   * @return
+   */
+  public boolean isFocusable(Element elem) {
+    return focusableTypes.contains(elem.getTagName().toLowerCase())
+        || elem.getTabIndex() >= 0;
   }
 
   /**
diff --git a/user/src/com/google/gwt/user/cellview/client/CellBrowser.java b/user/src/com/google/gwt/user/cellview/client/CellBrowser.java
index 8dcd61d..2ef939b 100644
--- a/user/src/com/google/gwt/user/cellview/client/CellBrowser.java
+++ b/user/src/com/google/gwt/user/cellview/client/CellBrowser.java
@@ -41,6 +41,7 @@
 import com.google.gwt.safehtml.shared.SafeHtml;
 import com.google.gwt.safehtml.shared.SafeHtmlBuilder;
 import com.google.gwt.safehtml.shared.SafeHtmlUtils;
+import com.google.gwt.user.cellview.client.HasKeyboardSelectionPolicy.KeyboardSelectionPolicy;
 import com.google.gwt.user.client.DOM;
 import com.google.gwt.user.client.Event;
 import com.google.gwt.user.client.ui.AbstractImagePrototype;
@@ -208,15 +209,20 @@
     private Object focusedKey;
 
     /**
-     * The value of the currently focused item.
+     * A boolean indicating that this widget is no longer used.
      */
-    private T focusedValue;
+    private boolean isDestroyed;
 
     /**
      * Indicates whether or not the focused value is open.
      */
     private boolean isFocusedOpen;
 
+    /**
+     * Temporary element used to create elements from HTML.
+     */
+    private final Element tmpElem = Document.get().createDivElement();
+
     public BrowserCellList(final Cell<T> cell, int level,
         ProvidesKey<T> keyProvider) {
       super(cell, cellListResources, keyProvider);
@@ -229,6 +235,17 @@
     }
 
     @Override
+    protected boolean isKeyboardNavigationSuppressed() {
+      /*
+       * Keyboard selection is never disabled in this list because we use it to
+       * track the open node, but we want to suppress keyboard navigation if the
+       * user disables it.
+       */
+      return KeyboardSelectionPolicy.DISABLED == CellBrowser.this.getKeyboardSelectionPolicy()
+          || super.isKeyboardNavigationSuppressed();
+    }
+
+    @Override
     protected void onBrowserEvent2(Event event) {
       super.onBrowserEvent2(event);
 
@@ -270,11 +287,9 @@
       int end = start + length;
       for (int i = start; i < end; i++) {
         T value = values.get(i - start);
-        Object key = getValueKey(value);
         boolean isSelected = selectionModel == null ? false
             : selectionModel.isSelected(value);
-        boolean isOpen = (focusedKey == null || !isFocusedOpen) ? false
-            : focusedKey.equals(key);
+        boolean isOpen = isOpen(i);
         StringBuilder classesBuilder = new StringBuilder();
         classesBuilder.append(i % 2 == 0 ? evenItem : oddItem);
         if (isOpen) {
@@ -285,7 +300,7 @@
         }
 
         SafeHtmlBuilder cellBuilder = new SafeHtmlBuilder();
-        cell.render(value, null, cellBuilder);
+        cell.render(value, getValueKey(value), cellBuilder);
 
         // Figure out which image to use.
         SafeHtml image;
@@ -316,15 +331,54 @@
               image, cellBuilder.toSafeHtml()));
         }
       }
+
+      // Update the child state.
+      updateChildState(this, true);
     }
 
     @Override
-    void doKeyboardSelection(Event event, T value, int indexOnPage) {
-      super.doKeyboardSelection(event, value, indexOnPage);
+    protected void setKeyboardSelected(int index, boolean selected,
+        boolean stealFocus) {
+      super.setKeyboardSelected(index, selected, stealFocus);
+      if (!isRowWithinBounds(index)) {
+        return;
+      }
 
-      // Open the selected row. If keyboard selection updates the selection
-      // model, this is a no-op.
-      setChildState(this, value, true, true, true);
+      // Update the style.
+      Element elem = getRowElement(index);
+      T value = getPresenter().getRowDataValue(index);
+      boolean isOpen = selected && isOpen(index);
+      setStyleName(elem, style.cellBrowserOpenItem(), isOpen);
+
+      // Update the image.
+      SafeHtml image = null;
+      if (isOpen) {
+        image = openImageHtml;
+      } else if (getTreeViewModel().isLeaf(value)) {
+        image = LEAF_IMAGE;
+      } else {
+        image = closedImageHtml;
+      }
+      tmpElem.setInnerHTML(image.asString());
+      elem.replaceChild(tmpElem.getFirstChildElement(),
+          elem.getFirstChildElement());
+
+      // Update the open state.
+      updateChildState(this, true);
+    }
+
+    /**
+     * Check if the specified index is currently open. An index is open if it is
+     * the keyboard selected index, there is an associated keyboard selected
+     * value, and the value is not a leaf.
+     * 
+     * @param index the index
+     * @return true if open, false if not
+     */
+    private boolean isOpen(int index) {
+      T value = getPresenter().getKeyboardSelectedRowValue();
+      return index == getKeyboardSelectedRow() && value != null
+          && !getTreeViewModel().isLeaf(value);
     }
 
     /**
@@ -338,14 +392,8 @@
       // Move to the child node.
       if (level < treeNodes.size() - 1) {
         TreeNodeImpl<?> treeNode = treeNodes.get(level + 1);
-        treeNode.display.setFocus(true);
-
-        // Select the element.
-        int selected = getKeyboardSelectedRow();
-        if (isRowWithinBounds(selected)) {
-          T value = getDisplayedItem(selected);
-          setChildState(this, value, true, true, true);
-        }
+        treeNode.display.getPresenter().setKeyboardSelectedRow(
+            treeNode.display.getKeyboardSelectedRow(), true);
       }
     }
 
@@ -415,7 +463,7 @@
 
     public int getChildCount() {
       assertNotDestroyed();
-      return display.getChildCount();
+      return display.getPresenter().getRowDataSize();
     }
 
     public C getChildValue(int index) {
@@ -432,7 +480,7 @@
 
     public TreeNodeImpl<?> getParent() {
       assertNotDestroyed();
-      return (display.level == 0) ? null : treeNodes.get(display.level - 1);
+      return getParentImpl();
     }
 
     public Object getValue() {
@@ -454,6 +502,16 @@
     }
 
     public boolean isDestroyed() {
+      if (nodeInfo != null) {
+        /*
+         * Flush the parent display because the user may have replaced this
+         * node, which would destroy it.
+         */
+        TreeNodeImpl<?> parent = getParentImpl();
+        if (parent != null && !parent.isDestroyed()) {
+          parent.display.getPresenter().flush();
+        }
+      }
       return nodeInfo == null;
     }
 
@@ -464,8 +522,22 @@
     public TreeNode setChildOpen(int index, boolean open, boolean fireEvents) {
       assertNotDestroyed();
       checkChildBounds(index);
-      return setChildState(display, getChildValue(index), open, fireEvents,
-          true);
+      if (open) {
+        // Open the child node.
+        display.getPresenter().setKeyboardSelectedRow(index, false);
+        return updateChildState(display, fireEvents);
+      } else {
+        // Close the child node if it is currently open.
+        if (index == display.getKeyboardSelectedRow()) {
+          display.getPresenter().clearKeyboardSelectedRowValue();
+          updateChildState(display, fireEvents);
+        }
+        return null;
+      }
+    }
+
+    BrowserCellList<C> getDisplay() {
+      return display;
     }
 
     /**
@@ -507,6 +579,7 @@
      * Unregister the list view and remove it from the widget.
      */
     private void destroy() {
+      display.isDestroyed = true;
       valueChangeHandler.removeHandler();
       display.setSelectionModel(null);
       nodeInfo.unsetDataDisplay();
@@ -520,8 +593,16 @@
      * @return the index of the open item, or -1 if not found
      */
     private int getOpenIndex() {
-      return display.isFocusedOpen ? display.indexOf(display.focusedValue)
-          : null;
+      return display.isFocusedOpen ? display.getKeyboardSelectedRow() : -1;
+    }
+
+    /**
+     * Get the parent node without checking if this node is destroyed.
+     * 
+     * @return the parent node, or null if the node has no parent
+     */
+    private TreeNodeImpl<?> getParentImpl() {
+      return (display.level == 0) ? null : treeNodes.get(display.level - 1);
     }
   }
 
@@ -832,6 +913,12 @@
   @Override
   public void setKeyboardSelectionPolicy(KeyboardSelectionPolicy policy) {
     super.setKeyboardSelectionPolicy(policy);
+
+    /*
+     * Set the policy on all lists. We use keyboard selection to track the open
+     * node, so we never actually disable keyboard selection on the lists.
+     */
+    policy = getKeyboardSelectionPolicyForLists();
     for (TreeNodeImpl<?> treeNode : treeNodes) {
       treeNode.display.setKeyboardSelectionPolicy(policy);
     }
@@ -883,7 +970,7 @@
    * @param nodeInfo the info about the node
    * @param value the value of the open node
    */
-  private <C> void appendTreeNode(final NodeInfo<C> nodeInfo, Object value) {
+  private <C> TreeNode appendTreeNode(final NodeInfo<C> nodeInfo, Object value) {
     // Create the list view.
     final int level = treeNodes.size();
     final BrowserCellList<C> view = createDisplay(nodeInfo, level);
@@ -924,6 +1011,7 @@
 
     // Scroll to the right.
     animation.scrollToEnd();
+    return treeNode;
   }
 
   /**
@@ -939,7 +1027,10 @@
     BrowserCellList<C> display = new BrowserCellList<C>(nodeInfo.getCell(),
         level, nodeInfo.getProvidesKey());
     display.setValueUpdater(nodeInfo.getValueUpdater());
-    display.setKeyboardSelectionPolicy(getKeyboardSelectionPolicy());
+
+    // Set the keyboard selection policy, but never disable it.
+    KeyboardSelectionPolicy keyboardPolicy = getKeyboardSelectionPolicyForLists();
+    display.setKeyboardSelectionPolicy(keyboardPolicy);
     return display;
   }
 
@@ -958,8 +1049,21 @@
   }
 
   /**
+   * Get the {@link KeyboardSelectionPolicy} to apply to lists. We use keyboard
+   * selection to track the open node, so we never actually disable keyboard
+   * selection on the lists.
+   * 
+   * @return the {@link KeyboardSelectionPolicy} to use on lists
+   */
+  private KeyboardSelectionPolicy getKeyboardSelectionPolicyForLists() {
+    KeyboardSelectionPolicy policy = getKeyboardSelectionPolicy();
+    return KeyboardSelectionPolicy.DISABLED == policy
+        ? KeyboardSelectionPolicy.ENABLED : policy;
+  }
+
+  /**
    * Get the {@link SplitLayoutPanel} used to lay out the views.
-   *
+   * 
    * @return the {@link SplitLayoutPanel}
    */
   private SplitLayoutPanel getSplitLayoutPanel() {
@@ -967,86 +1071,6 @@
   }
 
   /**
-   * Set the open state of a tree node.
-   * 
-   * @param cellList the CellList that changed state.
-   * @param value the value to open
-   * @param open true to open, false to close
-   * @param fireEvents true to fireEvents
-   * @return the open {@link TreeNode}, or null if not opened
-   */
-  private <C> TreeNode setChildState(BrowserCellList<C> cellList, C value,
-      boolean open, boolean fireEvents, boolean redraw) {
-
-    // Get the key of the value to open.
-    Object newKey = cellList.getValueKey(value);
-
-    if (open) {
-      if (newKey == null) {
-        // Early exit if opening but the specified node has no key.
-        return null;
-      } else if (newKey.equals(cellList.focusedKey)) {
-        // Early exit if opening but the specified node is already open.
-        return cellList.isFocusedOpen ? treeNodes.get(cellList.level + 1)
-            : null;
-      }
-
-      // Close the currently open node.
-      if (cellList.focusedKey != null) {
-        setChildState(cellList, cellList.focusedValue, false, fireEvents, false);
-      }
-
-      // Update the cell so it renders the styles correctly.
-      cellList.focusedValue = value;
-      cellList.focusedKey = cellList.getValueKey(value);
-
-      // Add the child node.
-      NodeInfo<?> childNodeInfo = isLeaf(value) ? null : getNodeInfo(value);
-      if (childNodeInfo != null) {
-        cellList.isFocusedOpen = true;
-        appendTreeNode(childNodeInfo, value);
-      } else {
-        cellList.isFocusedOpen = false;
-      }
-
-      // Refresh the display to update the styles for this node.
-      if (redraw) {
-        treeNodes.get(cellList.level).display.redraw();
-      }
-
-      if (cellList.isFocusedOpen) {
-        TreeNodeImpl<?> node = treeNodes.get(cellList.level + 1);
-        if (fireEvents) {
-          OpenEvent.fire(this, node);
-        }
-        return node.isDestroyed() ? null : node;
-      }
-      return null;
-    } else {
-      // Early exit if closing and the specified node or all nodes are closed.
-      if (cellList.focusedKey == null || !cellList.focusedKey.equals(newKey)) {
-        return null;
-      }
-
-      // Close the node.
-      TreeNode closedNode = (cellList.isFocusedOpen && (treeNodes.size() > cellList.level + 1))
-          ? treeNodes.get(cellList.level + 1) : null;
-      trimToLevel(cellList.level);
-
-      // Refresh the display to update the styles for this node.
-      if (redraw) {
-        treeNodes.get(cellList.level).display.redraw();
-      }
-
-      if (fireEvents && closedNode != null) {
-        CloseEvent.fire(this, closedNode);
-      }
-    }
-
-    return null;
-  }
-
-  /**
    * Reduce the number of {@link HasData}s down to the specified level.
    *
    * @param level the level to trim to
@@ -1067,8 +1091,83 @@
     if (level < treeNodes.size()) {
       TreeNodeImpl<?> node = treeNodes.get(level);
       node.display.focusedKey = null;
-      node.display.focusedValue = null;
       node.display.isFocusedOpen = false;
     }
   }
+
+  /**
+   * Update the state of a child node based on the keyboard selection of the
+   * specified {@link BrowserCellList}. This method will open/close child
+   * {@link TreeNode}s as needed.
+   * 
+   * @param cellList the CellList that changed state.
+   * @param value the value to open
+   * @param open true to open, false to close
+   * @param fireEvents true to fireEvents
+   * @return the open {@link TreeNode}, or null if not opened
+   */
+  private <C> TreeNode updateChildState(BrowserCellList<C> cellList,
+      boolean fireEvents) {
+    /*
+     * Verify that the specified list is still in the browser. It possible for
+     * the list to receive deferred updates after it has been removed 
+     */
+    if (cellList.isDestroyed) {
+      return null;
+    }
+
+    // Get the key of the value to open.
+    C newValue = cellList.getPresenter().getKeyboardSelectedRowValue();
+    Object newKey = cellList.getValueKey(newValue);
+
+    // Close the current open node.
+    TreeNode closedNode = null;
+    if (cellList.focusedKey != null && cellList.isFocusedOpen
+        && !cellList.focusedKey.equals(newKey)) {
+      // Get the node to close.
+      closedNode = (treeNodes.size() > cellList.level + 1)
+          ? treeNodes.get(cellList.level + 1) : null;
+
+      // Close the node.
+      trimToLevel(cellList.level);
+    }
+
+    // Open the new node.
+    TreeNode openNode = null;
+    boolean justOpenedNode = false;
+    if (newKey != null) {
+      if (newKey.equals(cellList.focusedKey)) {
+        // The node is already open.
+        openNode = cellList.isFocusedOpen ? treeNodes.get(cellList.level + 1)
+            : null;
+      } else {
+        // Add the child node.
+        cellList.focusedKey = newKey;
+        NodeInfo<?> childNodeInfo = isLeaf(newValue) ? null
+            : getNodeInfo(newValue);
+        if (childNodeInfo != null) {
+          cellList.isFocusedOpen = true;
+          justOpenedNode = true;
+          openNode = appendTreeNode(childNodeInfo, newValue);
+        }
+      }
+    }
+
+    /*
+     * Fire event. We fire events after updating the view in case user event
+     * handlers modify the open state of nodes, which would interrupt the
+     * process.
+     */
+    if (fireEvents) {
+      if (closedNode != null) {
+        CloseEvent.fire(this, closedNode);
+      }
+      if (openNode != null && justOpenedNode) {
+        OpenEvent.fire(this, openNode);
+      }
+    }
+
+    // Return the open node if it is still open.
+    return (openNode == null || openNode.isDestroyed()) ? null : openNode;
+  }
 }
diff --git a/user/src/com/google/gwt/user/cellview/client/CellList.java b/user/src/com/google/gwt/user/cellview/client/CellList.java
index 2906315..37f7c8c 100644
--- a/user/src/com/google/gwt/user/cellview/client/CellList.java
+++ b/user/src/com/google/gwt/user/cellview/client/CellList.java
@@ -239,6 +239,7 @@
    *           page
    */
   public Element getRowElement(int indexOnPage) {
+    getPresenter().flush();
     checkRowBounds(indexOnPage);
     if (childContainer.getChildCount() > indexOnPage) {
       return childContainer.getChild(indexOnPage).cast();
@@ -335,8 +336,12 @@
 
   @Override
   protected Element getKeyboardSelectedElement() {
+    // Do not use getRowElement() because that will flush the presenter.
     int rowIndex = getKeyboardSelectedRow();
-    return isRowWithinBounds(rowIndex) ? getRowElement(rowIndex) : null;
+    if (childContainer.getChildCount() > rowIndex) {
+      return childContainer.getChild(rowIndex).cast();
+    }
+    return null;
   }
 
   @Override
@@ -360,13 +365,14 @@
     if (!Element.is(eventTarget)) {
       return;
     }
-    Element target = event.getEventTarget().cast();
+    final Element target = event.getEventTarget().cast();
 
     // Forward the event to the cell.
     String idxString = "";
-    while ((target != null)
-        && ((idxString = target.getAttribute("__idx")).length() == 0)) {
-      target = target.getParentElement();
+    Element cellTarget = target;
+    while ((cellTarget != null)
+        && ((idxString = cellTarget.getAttribute("__idx")).length() == 0)) {
+      cellTarget = cellTarget.getParentElement();
     }
     if (idxString.length() > 0) {
       // Select the item if the cell does not consume events. Selection occurs
@@ -382,16 +388,22 @@
       }
 
       // Get the cell parent before doing selection in case the list is redrawn.
-      Element cellParent = getCellParent(target);
+      Element cellParent = getCellParent(cellTarget);
       T value = getDisplayedItem(indexOnPage);
       if (isMouseDown && !cell.handlesSelection()) {
         doSelection(event, value, indexOnPage);
       }
 
       // Focus on the cell.
-      if ("focus".equals(eventType) || isMouseDown) {
-        isFocused = true;
-        doKeyboardSelection(event, value, indexOnPage);
+      if (isMouseDown
+          && getPresenter().getKeyboardSelectedRowInView() != indexOnPage) {
+        /*
+         * If the selected element is natively focusable, then we do not want to
+         * steal focus away from it.
+         */
+        boolean isFocusable = CellBasedWidgetImpl.get().isFocusable(target);
+        isFocused = isFocused || isFocusable;
+        getPresenter().setKeyboardSelectedRow(indexOnPage, !isFocusable);
       }
 
       // Fire the event to the cell if the list has not been refreshed.
@@ -483,24 +495,17 @@
     }
   }
 
+  /**
+   * @deprecated this method is never called by AbstractHasData, render the
+   *             selected styles in
+   *             {@link #renderRowValues(SafeHtmlBuilder, List, int, SelectionModel)}
+   */
   @Override
+  @Deprecated
   protected void setSelected(Element elem, boolean selected) {
     setStyleName(elem, style.cellListSelectedItem(), selected);
   }
 
-  /**
-   * Called when the user selects a cell with the mouse or tab key.
-   *
-   * @param event the event
-   * @param value the value that is selected
-   * @param indexOnPage the index on the page
-   */
-  void doKeyboardSelection(Event event, T value, int indexOnPage) {
-    if (getPresenter().getKeyboardSelectedRow() != indexOnPage) {
-      getPresenter().setKeyboardSelectedRow(indexOnPage, false);
-    }
-  }
-
   @Override
   void setLoadingState(LoadingState state) {
     showOrHide(emptyMessageElem, state == LoadingState.EMPTY);
diff --git a/user/src/com/google/gwt/user/cellview/client/CellTable.java b/user/src/com/google/gwt/user/cellview/client/CellTable.java
index 33e05e3..305c502 100644
--- a/user/src/com/google/gwt/user/cellview/client/CellTable.java
+++ b/user/src/com/google/gwt/user/cellview/client/CellTable.java
@@ -459,29 +459,6 @@
 
   private int keyboardSelectedColumn = 0;
 
-  /**
-   * Indicates whether or not the scheduled redraw has been canceled.
-   */
-  private boolean redrawCancelled;
-
-  /**
-   * The command used to redraw the table after adding columns.
-   */
-  private final Scheduler.ScheduledCommand redrawCommand = new Scheduler.ScheduledCommand() {
-    public void execute() {
-      redrawScheduled = false;
-      if (redrawCancelled) {
-        redrawCancelled = false;
-        return;
-      }
-      redraw();
-    }
-  };
-
-  /**
-   * Indicates whether or not a redraw is scheduled.
-   */
-  private boolean redrawScheduled;
   private RowStyles<T> rowStyles;
   private final Style style;
   private final TableElement table;
@@ -653,7 +630,7 @@
     }
     CellBasedWidgetImpl.get().sinkEvents(this, consumedEvents);
 
-    scheduleRedraw();
+    redraw();
   }
 
   /**
@@ -701,7 +678,7 @@
     addColumn(col, new SafeHtmlHeader(headerHtml), new SafeHtmlHeader(
         footerHtml));
   }
-  
+
   /**
    * Add a style name to the {@link TableColElement} at the specified index,
    * creating it if necessary.
@@ -743,6 +720,7 @@
    *           current page
    */
   public TableRowElement getRowElement(int row) {
+    getPresenter().flush();
     checkRowBounds(row);
     NodeList<TableRowElement> rows = tbody.getRows();
     return rows.getLength() > row ? rows.getItem(row) : null;
@@ -805,7 +783,7 @@
     }
 
     // Redraw the table asynchronously.
-    scheduleRedraw();
+    redraw();
 
     // We don't unsink events because other handlers or user code may have sunk
     // them intentionally.
@@ -867,9 +845,11 @@
 
   @Override
   protected Element getKeyboardSelectedElement() {
+    // Do not use getRowElement() because that will flush the presenter.
     int rowIndex = getKeyboardSelectedRow();
-    if (isRowWithinBounds(rowIndex) && columns.size() > 0) {
-      TableRowElement tr = getRowElement(rowIndex);
+    NodeList<TableRowElement> rows = tbody.getRows();
+    if (rowIndex < rows.getLength() && columns.size() > 0) {
+      TableRowElement tr = rows.getItem(rowIndex);
       TableCellElement td = tr.getCells().getItem(keyboardSelectedColumn);
       return getCellParent(td);
     }
@@ -900,7 +880,7 @@
     if (!Element.is(eventTarget)) {
       return;
     }
-    Element target = event.getEventTarget().cast();
+    final Element target = event.getEventTarget().cast();
 
     // Ignore keydown events unless the cell is in edit mode
     String eventType = event.getType();
@@ -937,13 +917,11 @@
     if (section == thead) {
       Header<?> header = headers.get(col);
       if (header != null && cellConsumesEventType(header.getCell(), eventType)) {
-
         header.onBrowserEvent(tableCell, event);
       }
     } else if (section == tfoot) {
       Header<?> footer = footers.get(col);
       if (footer != null && cellConsumesEventType(footer.getCell(), eventType)) {
-
         footer.onBrowserEvent(tableCell, event);
       }
     } else if (section == tbody) {
@@ -963,16 +941,15 @@
         setRowStyleName(hoveringRow, style.cellTableHoveredRow(),
             style.cellTableHoveredRowCell(), false);
         hoveringRow = null;
-      } else if ("focus".equals(eventType) || isMouseDown) {
+      } else if (isMouseDown
+          && ((getPresenter().getKeyboardSelectedRowInView() != row)
+          || (keyboardSelectedColumn != col))) {
         // Move keyboard focus. Since the user clicked, allow focus to go to a
         // non-interactive column.
-        isFocused = true;
-        if (getPresenter().getKeyboardSelectedRow() != row
-            || keyboardSelectedColumn != col) {
-          deselectKeyboardRow(getKeyboardSelectedRow());
-          keyboardSelectedColumn = col;
-          getPresenter().setKeyboardSelectedRow(row, false);
-        }
+        boolean isFocusable = CellBasedWidgetImpl.get().isFocusable(target);
+        isFocused = isFocused || isFocusable;
+        keyboardSelectedColumn = col;
+        getPresenter().setKeyboardSelectedRow(row, !isFocusable);
       }
 
       // Update selection. Selection occurs before firing the event to the cell
@@ -1004,25 +981,6 @@
   }
 
   @Override
-  protected void onUpdateSelection() {
-    // Refresh headers.
-    for (Header<?> header : headers) {
-      if (header != null && header.getCell().dependsOnSelection()) {
-        createHeaders(false);
-        break;
-      }
-    }
-
-    // Refresh footers.
-    for (Header<?> footer : footers) {
-      if (footer != null && footer.getCell().dependsOnSelection()) {
-        createHeaders(true);
-        break;
-      }
-    }
-  }
-
-  @Override
   protected void renderRowValues(SafeHtmlBuilder sb, List<T> values, int start,
       SelectionModel<? super T> selectionModel) {
     createHeadersAndFooters();
@@ -1117,10 +1075,6 @@
 
   @Override
   protected void replaceAllChildren(List<T> values, SafeHtml html) {
-    // Cancel any pending redraw.
-    if (redrawScheduled) {
-      redrawCancelled = true;
-    }
     TABLE_IMPL.replaceAllRows(CellTable.this, tbody,
         CellBasedWidgetImpl.get().processHtml(html));
   }
@@ -1144,15 +1098,27 @@
     }
 
     TableRowElement tr = getRowElement(index);
-    TableCellElement td = tr.getCells().getItem(keyboardSelectedColumn);
-    final com.google.gwt.user.client.Element cellParent = getCellParent(td).cast();
-    if (!selected || isFocused || stealFocus) {
-      setRowStyleName(tr, style.cellTableKeyboardSelectedRow(),
-          style.cellTableKeyboardSelectedRowCell(), selected);
-      setStyleName(td, style.cellTableKeyboardSelectedCell(), selected);
+    String cellStyle = style.cellTableKeyboardSelectedCell();
+    boolean updatedSelection = !selected || isFocused || stealFocus;
+    setRowStyleName(tr, style.cellTableKeyboardSelectedRow(),
+        style.cellTableKeyboardSelectedRowCell(), selected);
+    NodeList<TableCellElement> cells = tr.getCells();
+    for (int i = 0; i < cells.getLength(); i++) {
+      TableCellElement td = cells.getItem(i);
+
+      // Update the selected style.
+      setStyleName(td, cellStyle, updatedSelection && selected
+          && i == keyboardSelectedColumn);
+
+      // Mark as focusable.
+      final com.google.gwt.user.client.Element cellParent = getCellParent(td).cast();
+      setFocusable(cellParent, selected && i == keyboardSelectedColumn);
     }
-    setFocusable(cellParent, selected);
+
+    // Move focus to the cell.
     if (selected && stealFocus) {
+      TableCellElement td = tr.getCells().getItem(keyboardSelectedColumn);
+      final com.google.gwt.user.client.Element cellParent = getCellParent(td).cast();
       CellBasedWidgetImpl.get().resetFocus(new Scheduler.ScheduledCommand() {
         public void execute() {
           cellParent.focus();
@@ -1161,7 +1127,13 @@
     }
   }
 
+  /**
+   * @deprecated this method is never called by AbstractHasData, render the
+   *             selected styles in
+   *             {@link #renderRowValues(SafeHtmlBuilder, List, int, SelectionModel)}
+   */
   @Override
+  @Deprecated
   protected void setSelected(Element elem, boolean selected) {
     TableRowElement tr = elem.cast();
     setRowStyleName(tr, style.cellTableSelectedRow(),
@@ -1249,10 +1221,6 @@
     createHeaders(true);
   }
 
-  private void deselectKeyboardRow(int row) {
-    setKeyboardSelected(row, false, false);
-  }
-
   /**
    * Get the {@link TableColElement} at the specified index, creating it if
    * necessary.
@@ -1380,7 +1348,6 @@
       if (nextColumn <= keyboardSelectedColumn) {
         // Wrap to the next row.
         if (presenter.hasKeyboardNext()) {
-          deselectKeyboardRow(oldRow);
           keyboardSelectedColumn = nextColumn;
           presenter.keyboardNext();
           event.preventDefault();
@@ -1388,9 +1355,8 @@
         }
       } else {
         // Reselect the row to move the selected column.
-        deselectKeyboardRow(oldRow);
         keyboardSelectedColumn = nextColumn;
-        setKeyboardSelected(oldRow, true, true);
+        getPresenter().setKeyboardSelectedRow(oldRow, true);
         event.preventDefault();
         return true;
       }
@@ -1399,7 +1365,6 @@
       if (prevColumn >= keyboardSelectedColumn) {
         // Wrap to the previous row.
         if (presenter.hasKeyboardPrev()) {
-          deselectKeyboardRow(oldRow);
           keyboardSelectedColumn = prevColumn;
           presenter.keyboardPrev();
           event.preventDefault();
@@ -1407,9 +1372,8 @@
         }
       } else {
         // Reselect the row to move the selected column.
-        deselectKeyboardRow(oldRow);
         keyboardSelectedColumn = prevColumn;
-        setKeyboardSelected(oldRow, true, true);
+        getPresenter().setKeyboardSelectedRow(oldRow, true);
         event.preventDefault();
         return true;
       }
@@ -1436,17 +1400,6 @@
   }
 
   /**
-   * Schedule a redraw for the end of the event loop.
-   */
-  private void scheduleRedraw() {
-    redrawCancelled = false;
-    if (!redrawScheduled) {
-      redrawScheduled = true;
-      Scheduler.get().scheduleFinally(redrawCommand);
-    }
-  }
-
-  /**
    * Show or hide the loading icon.
    *
    * @param visible true to show, false to hide.
diff --git a/user/src/com/google/gwt/user/cellview/client/CellTree.java b/user/src/com/google/gwt/user/cellview/client/CellTree.java
index bbe2b4d..90b2ddd 100644
--- a/user/src/com/google/gwt/user/cellview/client/CellTree.java
+++ b/user/src/com/google/gwt/user/cellview/client/CellTree.java
@@ -18,7 +18,6 @@
 import com.google.gwt.animation.client.Animation;
 import com.google.gwt.core.client.GWT;
 import com.google.gwt.core.client.Scheduler;
-import com.google.gwt.core.client.Scheduler.ScheduledCommand;
 import com.google.gwt.dom.client.Element;
 import com.google.gwt.dom.client.Style.Display;
 import com.google.gwt.dom.client.Style.Overflow;
@@ -521,6 +520,11 @@
    */
   boolean isRefreshing;
 
+  /**
+   * The hidden root node in the tree. Visible for testing.
+   */
+  final CellTreeNodeView<?> rootNode;
+
   private char accessKey = 0;
 
   /**
@@ -554,11 +558,6 @@
   private boolean isAnimationEnabled;
 
   /**
-   * The deferred command used to keyboard select a node. 
-   */
-  private ScheduledCommand keyboardSelectCommand;
-
-  /**
    * The {@link CellTreeNodeView} whose children are currently being selected
    * using the keyboard.
    */
@@ -580,11 +579,6 @@
   private final SafeHtml openImageTopHtml;
 
   /**
-   * The hidden root node in the tree.
-   */
-  private final CellTreeNodeView<?> rootNode;
-
-  /**
    * The styles used by this widget.
    */
   private final Style style;
@@ -731,11 +725,11 @@
       }
     }
 
-    Element target = event.getEventTarget().cast();
+    final Element target = event.getEventTarget().cast();
     ArrayList<Element> chain = new ArrayList<Element>();
     collectElementChain(chain, getElement(), target);
 
-    boolean isMouseDown = "mousedown".equals(eventType);
+    final boolean isMouseDown = "mousedown".equals(eventType);
     final CellTreeNodeView<?> nodeView = findItemByChain(chain, 0, rootNode);
     if (nodeView != null && nodeView != rootNode) {
       if (isMouseDown) {
@@ -754,19 +748,14 @@
       // Forward the event to the cell
       if (nodeView.getSelectionElement().isOrHasChild(target)) {
         // Move the keyboard focus to the clicked item.
-        if ("focus".equals(eventType) || isMouseDown) {
-          // Wait until any pending blur event has fired.
-          final boolean targetsCellParent = nodeView.getCellParent().isOrHasChild(target);
-          keyboardSelectCommand = new ScheduledCommand() {
-            public void execute() {
-              if (keyboardSelectCommand == this && !nodeView.isDestroyed()) {
-                isFocused = true;
-                keyboardSelectCommand = null;
-                keyboardSelect(nodeView, !targetsCellParent);
-              }
-            }
-          };
-          Scheduler.get().scheduleDeferred(keyboardSelectCommand);
+        if (isMouseDown) {
+          /*
+           * If the selected element is natively focusable, then we do not want to
+           * steal focus away from it.
+           */
+          boolean isFocusable = CellBasedWidgetImpl.get().isFocusable(target);
+          isFocused = isFocused || isFocusable;
+          keyboardSelect(nodeView, !isFocusable);
         }
 
         nodeView.fireEventToCell(event);
diff --git a/user/src/com/google/gwt/user/cellview/client/CellTreeNodeView.java b/user/src/com/google/gwt/user/cellview/client/CellTreeNodeView.java
index 2a6c71b..4b87828 100644
--- a/user/src/com/google/gwt/user/cellview/client/CellTreeNodeView.java
+++ b/user/src/com/google/gwt/user/cellview/client/CellTreeNodeView.java
@@ -36,7 +36,6 @@
 import com.google.gwt.safehtml.shared.SafeHtml;
 import com.google.gwt.safehtml.shared.SafeHtmlBuilder;
 import com.google.gwt.safehtml.shared.SafeHtmlUtils;
-import com.google.gwt.user.cellview.client.HasDataPresenter.ElementIterator;
 import com.google.gwt.user.cellview.client.HasDataPresenter.LoadingState;
 import com.google.gwt.user.cellview.client.HasKeyboardSelectionPolicy.KeyboardSelectionPolicy;
 import com.google.gwt.user.client.ui.UIObject;
@@ -103,22 +102,6 @@
         return handlerManger.addHandler(type, handler);
       }
 
-      public boolean dependsOnSelection() {
-        return cell.dependsOnSelection();
-      }
-
-      public int getChildCount() {
-        return childContainer.getChildCount();
-      }
-
-      public ElementIterator getChildIterator() {
-        return new HasDataPresenter.DefaultElementIterator(this,
-            childContainer.getFirstChildElement());
-      }
-
-      public void onUpdateSelection() {
-      }
-
       public void render(SafeHtmlBuilder sb, List<C> values, int start,
           SelectionModel<? super C> selectionModel) {
         // Cache the style names that will be used for each child.
@@ -197,7 +180,8 @@
         }
       }
 
-      public void replaceAllChildren(List<C> values, SafeHtml html) {
+      public void replaceAllChildren(List<C> values, SafeHtml html,
+          boolean stealFocus) {
         // Hide the child container so we can animate it.
         if (nodeView.tree.isAnimationEnabled()) {
           nodeView.ensureAnimationFrame().getStyle().setDisplay(Display.NONE);
@@ -233,8 +217,10 @@
         }
       }
 
-      public void replaceChildren(List<C> values, int start, SafeHtml html) {
-        Map<Object, CellTreeNodeView<?>> savedViews = saveChildState(values, 0);
+      public void replaceChildren(List<C> values, int start, SafeHtml html,
+          boolean stealFocus) {
+        Map<Object, CellTreeNodeView<?>> savedViews = saveChildState(values,
+            start);
 
         nodeView.tree.isRefreshing = true;
         Element newChildren = AbstractHasData.convertToElements(nodeView.tree,
@@ -243,7 +229,7 @@
             newChildren, start, html);
         nodeView.tree.isRefreshing = false;
 
-        loadChildState(values, 0, savedViews);
+        loadChildState(values, start, savedViews);
       }
 
       public void resetFocus() {
@@ -263,11 +249,6 @@
         showOrHide(nodeView.emptyMessageElem, state == LoadingState.EMPTY);
       }
 
-      public void setSelected(Element elem, boolean selected) {
-        setStyleName(getSelectionElement(elem),
-            nodeView.tree.getStyle().cellTreeSelectedItem(), selected);
-      }
-
       /**
        * Reload the open children after rendering new items in this node.
        *
@@ -283,7 +264,7 @@
         ProvidesKey<C> keyProvider = nodeInfo.getProvidesKey();
 
         Element container = nodeView.ensureChildContainer();
-        Element childElem = container.getFirstChildElement();
+        Element childElem = container.getChild(start).cast();
         CellTreeNodeView<?> keyboardSelected = nodeView.tree.getKeyboardSelectedNode();
         for (int i = start; i < end; i++) {
           C childValue = values.get(i - start);
@@ -428,9 +409,13 @@
       this.nodeView = nodeView;
       cell = nodeInfo.getCell();
 
+      // Create a presenter.
       presenter = new HasDataPresenter<C>(this, new View(
           nodeView.ensureChildContainer()), pageSize, nodeInfo.getProvidesKey());
 
+      // Disable keyboard selection because it is handled by CellTree.
+      presenter.setKeyboardSelectionPolicy(KeyboardSelectionPolicy.DISABLED);
+
       // Use a pager to update buttons.
       presenter.addRowCountChangeHandler(new RowCountChangeEvent.Handler() {
         public void onRowCountChange(RowCountChangeEvent event) {
@@ -529,12 +514,14 @@
 
     public int getChildCount() {
       assertNotDestroyed();
+      flush();
       return nodeView.getChildCount();
     }
 
     public Object getChildValue(int index) {
       assertNotDestroyed();
       checkChildBounds(index);
+      flush();
       return nodeView.getChildNode(index).value;
     }
 
@@ -546,7 +533,7 @@
 
     public TreeNode getParent() {
       assertNotDestroyed();
-      return nodeView.isRootNode() ? null : nodeView.parentNode.treeNode;
+      return getParentImpl();
     }
 
     public Object getValue() {
@@ -556,16 +543,28 @@
     public boolean isChildLeaf(int index) {
       assertNotDestroyed();
       checkChildBounds(index);
+      flush();
       return nodeView.getChildNode(index).isLeaf();
     }
 
     public boolean isChildOpen(int index) {
       assertNotDestroyed();
       checkChildBounds(index);
+      flush();
       return nodeView.getChildNode(index).isOpen();
     }
 
     public boolean isDestroyed() {
+      if (!nodeView.isDestroyed) {
+        /*
+         * Flush the parent display because the user may have replaced this
+         * node, which would destroy it.
+         */
+        TreeNodeImpl parent = getParentImpl();
+        if (parent != null && !parent.isDestroyed()) {
+          parent.flush();
+        }
+      }
       return nodeView.isDestroyed || !nodeView.isOpen();
     }
 
@@ -600,6 +599,24 @@
         throw new IndexOutOfBoundsException();
       }
     }
+
+    /**
+     * Flush pending changes in the view.
+     */
+    private void flush() {
+      if (nodeView.listView != null) {
+        nodeView.listView.presenter.flush();
+      }
+    }
+
+    /**
+     * Get the parent node without checking if this node is destroyed.
+     * 
+     * @return the parent node, or null if the node has no parent
+     */
+    private TreeNodeImpl getParentImpl() {
+      return nodeView.isRootNode() ? null : nodeView.parentNode.treeNode;
+    }
   }
 
   /**
@@ -1173,6 +1190,10 @@
    * @param stealFocus true to steal focus
    */
   void setKeyboardSelected(boolean selected, boolean stealFocus) {
+    if (tree.isKeyboardSelectionDisabled()) {
+      return;
+    }
+
     // Apply the selected style.
     if (!selected || tree.isFocused || stealFocus) {
       setKeyboardSelectedStyle(selected);
diff --git a/user/src/com/google/gwt/user/cellview/client/HasDataPresenter.java b/user/src/com/google/gwt/user/cellview/client/HasDataPresenter.java
index e158c81..a130edd 100644
--- a/user/src/com/google/gwt/user/cellview/client/HasDataPresenter.java
+++ b/user/src/com/google/gwt/user/cellview/client/HasDataPresenter.java
@@ -1,12 +1,12 @@
 /*
  * Copyright 2010 Google Inc.
- *
+ * 
  * Licensed under the Apache License, Version 2.0 (the "License"); you may not
  * use this file except in compliance with the License. You may obtain a copy of
  * the License at
- *
+ * 
  * http://www.apache.org/licenses/LICENSE-2.0
- *
+ * 
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
@@ -15,12 +15,15 @@
  */
 package com.google.gwt.user.cellview.client;
 
+import com.google.gwt.core.client.Scheduler;
+import com.google.gwt.core.client.Scheduler.ScheduledCommand;
 import com.google.gwt.dom.client.Element;
 import com.google.gwt.event.shared.EventHandler;
 import com.google.gwt.event.shared.GwtEvent;
 import com.google.gwt.event.shared.HandlerRegistration;
 import com.google.gwt.safehtml.shared.SafeHtml;
 import com.google.gwt.safehtml.shared.SafeHtmlBuilder;
+import com.google.gwt.user.cellview.client.HasKeyboardSelectionPolicy.KeyboardSelectionPolicy;
 import com.google.gwt.view.client.HasData;
 import com.google.gwt.view.client.HasKeyProvider;
 import com.google.gwt.view.client.ProvidesKey;
@@ -34,8 +37,8 @@
 import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
-import java.util.NoSuchElementException;
 import java.util.Set;
+import java.util.TreeSet;
 
 /**
  * <p>
@@ -50,63 +53,27 @@
  * the presenter, which then updates the widget via the view. This keeps the
  * user facing API simpler.
  * <p>
- *
+ * <p>
+ * Updates are not pushed to the view immediately. Instead, the presenter
+ * collects updates and resolves them all in a finally command. This reduces the
+ * total number of DOM manipulations, and makes it easier to handle side effects
+ * in user code triggered by the rendering pass. The view is responsible for
+ * called {@link #flush()} to force the presenter to synchronize the view when
+ * needed.
+ * </p>
+ * 
  * @param <T> the data type of items in the list
  */
 class HasDataPresenter<T> implements HasData<T>, HasKeyProvider<T>,
     HasKeyboardPagingPolicy {
 
   /**
-   * Default iterator over DOM elements.
-   */
-  static class DefaultElementIterator implements ElementIterator {
-    private Element current;
-    private Element next;
-    private final View<?> view;
-
-    public DefaultElementIterator(View<?> view, Element first) {
-      this.view = view;
-      next = first;
-    }
-
-    public boolean hasNext() {
-      return next != null;
-    }
-
-    public Element next() {
-      if (!hasNext()) {
-        throw new NoSuchElementException();
-      }
-      current = next;
-      next = next.getNextSiblingElement();
-      return current;
-    }
-
-    public void remove() {
-      throw new UnsupportedOperationException();
-    }
-
-    /**
-     * Set the selection state of the current element.
-     *
-     * @param selected the selection state
-     * @throws IllegalStateException if {@link #next()} has not been called
-     */
-    public void setSelected(boolean selected) throws IllegalStateException {
-      if (current == null) {
-        throw new IllegalStateException();
-      }
-      view.setSelected(current, selected);
-    }
-  }
-
-  /**
    * An iterator over DOM elements.
    */
   static interface ElementIterator extends Iterator<Element> {
     /**
      * Set the selection state of the current element.
-     *
+     * 
      * @param selected the selection state
      * @throws IllegalStateException if {@link #next()} has not been called
      */
@@ -125,14 +92,14 @@
 
   /**
    * The view that this presenter presents.
-   *
+   * 
    * @param <T> the data type
    */
   static interface View<T> {
 
     /**
      * Add a handler to the view.
-     *
+     * 
      * @param <H> the handler type
      * @param handler the handler to add
      * @param type the event type
@@ -141,38 +108,12 @@
         GwtEvent.Type<H> type);
 
     /**
-     * Check whether or not the cells in the view depend on the selection state.
-     *
-     * @return true if cells depend on selection, false if not
-     */
-    boolean dependsOnSelection();
-
-    /**
-     * Get the physical child count.
-     *
-     * @return the child count
-     */
-    int getChildCount();
-
-    /**
-     * Get an iterator over the children of the view.
-     *
-     * @return the iterator
-     */
-    ElementIterator getChildIterator();
-
-    /**
-     * Called when selection changes.
-     */
-    void onUpdateSelection();
-
-    /**
      * Construct the HTML that represents the list of values, taking the
      * selection state into account.
-     *
+     * 
      * @param sb the {@link SafeHtmlBuilder} to build into
      * @param values the values to render
-     * @param start the start index that is being rendered
+     * @param start the absolute start index that is being rendered
      * @param selectionModel the {@link SelectionModel}
      */
     void render(SafeHtmlBuilder sb, List<T> values, int start,
@@ -180,23 +121,26 @@
 
     /**
      * Replace all children with the specified html.
-     *
+     * 
      * @param values the values of the new children
      * @param html the html to render in the child
+     * @param stealFocus true if the row should steal focus, false if not
      */
-    void replaceAllChildren(List<T> values, SafeHtml html);
+    void replaceAllChildren(List<T> values, SafeHtml html, boolean stealFocus);
 
     /**
      * Convert the specified HTML into DOM elements and replace the existing
      * elements starting at the specified index. If the number of children
      * specified exceeds the existing number of children, the remaining children
      * should be appended.
-     *
+     * 
      * @param values the values of the new children
-     * @param start the start index to be replaced
+     * @param start the start index to be replaced, relative to the pageStart
      * @param html the HTML to convert
+     * @param stealFocus true if the row should steal focus, false if not
      */
-    void replaceChildren(List<T> values, int start, SafeHtml html);
+    void replaceChildren(List<T> values, int start, SafeHtml html,
+        boolean stealFocus);
 
     /**
      * Re-establish focus on an element within the view if the view already had
@@ -206,7 +150,7 @@
 
     /**
      * Update an element to reflect its keyboard selected state.
-     *
+     * 
      * @param index the index of the element relative to page start
      * @param selected true if selected, false if not
      * @param stealFocus true if the row should steal focus, false if not
@@ -215,18 +159,190 @@
 
     /**
      * Set the current loading state of the data.
-     *
+     * 
      * @param state the loading state
      */
     void setLoadingState(LoadingState state);
+  }
+
+  /**
+   * Represents the state of the presenter.
+   * 
+   * @param <T> the data type of the presenter
+   */
+  private static class DefaultState<T> implements State<T> {
+    int keyboardSelectedRow = 0;
+    T keyboardSelectedRowValue = null;
+    int pageSize;
+    int pageStart = 0;
+    int rowCount = 0;
+    boolean rowCountIsExact = false;
+    final List<T> rowData = new ArrayList<T>();
+    final Set<Integer> selectedRows = new HashSet<Integer>();
+
+    public DefaultState(int pageSize) {
+      this.pageSize = pageSize;
+    }
+
+    public int getKeyboardSelectedRow() {
+      return keyboardSelectedRow;
+    }
+
+    public T getKeyboardSelectedRowValue() {
+      return keyboardSelectedRowValue;
+    }
+
+    public int getPageSize() {
+      return pageSize;
+    }
+
+    public int getPageStart() {
+      return pageStart;
+    }
+
+    public int getRowCount() {
+      return rowCount;
+    }
+
+    public int getRowDataSize() {
+      return rowData.size();
+    }
+
+    public T getRowDataValue(int index) {
+      return rowData.get(index);
+    }
+
+    public boolean isRowCountExact() {
+      return rowCountIsExact;
+    }
 
     /**
-     * Update an element to reflect its selected state.
-     *
-     * @param elem the element to update
-     * @param selected true if selected, false if not
+     * {@inheritDoc}
+     * 
+     * <p>
+     * The set of selected rows is not maintained in the pending state. This
+     * method should only be called on the state after it has been resolved.
+     * </p>
      */
-    void setSelected(Element elem, boolean selected);
+    public boolean isRowSelected(int index) {
+      return selectedRows.contains(index);
+    }
+  }
+
+  /**
+   * Represents the pending state of the presenter.
+   * 
+   * @param <T> the data type of the presenter
+   */
+  private static class PendingState<T> extends DefaultState<T> {
+
+    /**
+     * A boolean indicating that the user has keyboard selected a new row.
+     */
+    private boolean keyboardSelectedRowChanged;
+
+    /**
+     * A boolean indicating that a change in keyboard selected should cause us
+     * to steal focus.
+     */
+    private boolean keyboardStealFocus = false;
+
+    /**
+     * Set to true if a redraw is required.
+     */
+    private boolean redrawRequired = false;
+
+    /**
+     * The list of ranges that have been replaced.
+     */
+    private final List<Range> replacedRanges = new ArrayList<Range>();
+
+    public PendingState(State<T> state) {
+      super(state.getPageSize());
+      this.keyboardSelectedRow = state.getKeyboardSelectedRow();
+      this.keyboardSelectedRowValue = state.getKeyboardSelectedRowValue();
+      this.pageSize = state.getPageSize();
+      this.pageStart = state.getPageStart();
+      this.rowCount = state.getRowCount();
+      this.rowCountIsExact = state.isRowCountExact();
+
+      // Copy the row data.
+      int rowDataSize = state.getRowDataSize();
+      for (int i = 0; i < rowDataSize; i++) {
+        this.rowData.add(state.getRowDataValue(i));
+      }
+
+      /*
+       * We do not copy the selected rows from the old state. They will be
+       * resolved from the SelectionModel.
+       */
+    }
+
+    /**
+     * Update the range of replaced data.
+     * 
+     * @param start the start index
+     * @param end the end index
+     */
+    public void replaceRange(int start, int end) {
+      replacedRanges.add(new Range(start, end - start));
+    }
+  }
+
+  /**
+   * Represents the state of the presenter.
+   * 
+   * @param <T> the data type of the presenter
+   */
+  private static interface State<T> {
+    /**
+     * Get the current keyboard selected row relative to page start. This value
+     * should never be negative.
+     */
+    int getKeyboardSelectedRow();
+
+    /**
+     * Get the last row value that was selected with the keyboard.
+     */
+    T getKeyboardSelectedRowValue();
+
+    /**
+     * Get the number of rows in the current page.
+     */
+    int getPageSize();
+
+    /**
+     * Get the absolute start index of the page.
+     */
+    int getPageStart();
+
+    /**
+     * Get the total number of rows.
+     */
+    int getRowCount();
+
+    /**
+     * Get the size of the row data.
+     */
+    int getRowDataSize();
+
+    /**
+     * Get a specific value from the row data.
+     */
+    T getRowDataValue(int index);
+
+    /**
+     * Get a boolean indicating whether the row count is exact or an estimate.
+     */
+    boolean isRowCountExact();
+
+    /**
+     * Check if a row index is selected.
+     * 
+     * @param index the row index
+     * @return true if selected, false if not
+     */
+    boolean isRowSelected(int index);
   }
 
   /**
@@ -236,18 +352,31 @@
    */
   static final int PAGE_INCREMENT = 30;
 
+  /**
+   * The maximum number of times we can try to {@link #resolvePendingState()}
+   * before we assume there is an infinite loop.
+   */
+  private static final int LOOP_MAXIMUM = 10;
+
+  /**
+   * The minimum number of rows that need to be replaced before we do a redraw.
+   */
+  private static final int REDRAW_MINIMUM = 5;
+
+  /**
+   * The threshold of new data after which we redraw the entire view instead of
+   * replacing specific rows.
+   * 
+   * TODO(jlabanca): Find the optimal value for the threshold.
+   */
+  private static final double REDRAW_THRESHOLD = 0.30;
+
   private final HasData<T> display;
 
   /**
-   * The current keyboard selected row relative to page start. This value should
-   * never be negative.
+   * A boolean indicating that we are in the process of resolving state.
    */
-  private int keyboardSelectedRow = 0;
-
-  /**
-   * The last row value that was selected with the keyboard.
-   */
-  private T keyboardSelectedRowValue;
+  private boolean isResolvingState;
 
   private KeyboardPagingPolicy keyboardPagingPolicy = KeyboardPagingPolicy.CHANGE_PAGE;
   private KeyboardSelectionPolicy keyboardSelectionPolicy = KeyboardSelectionPolicy.ENABLED;
@@ -257,43 +386,42 @@
   /**
    * As an optimization, keep track of the last HTML string that we rendered. If
    * the contents do not change the next time we render, then we don't have to
-   * set inner html.
+   * set inner html. This is useful for apps that continuously refresh the view.
    */
   private SafeHtml lastContents = null;
 
-  private int pageSize;
-  private int pageStart = 0;
+  /**
+   * The pending state of the presenter to be pushed to the view.
+   */
+  private PendingState<T> pendingState;
 
   /**
-   * Set to true when the page start changes, and we need to do a full refresh.
+   * The command used to resolve the pending state.
    */
-  private boolean pageStartChangedSinceRender;
-
-  private int rowCount = 0;
-
-  private boolean rowCountIsExact;
+  private ScheduledCommand pendingStateCommand;
 
   /**
-   * The local cache of data in the view. The 0th index in the list corresponds
-   * to the value at pageStart.
+   * A counter used to detect infinite loops in {@link #resolvePendingState()}.
+   * An infinite loop can occur if user code, such as reading the
+   * {@link SelectionModel}, causes the table to have a pending state.
    */
-  private final List<T> rowData = new ArrayList<T>();
-
-  /**
-   * A local cache of the currently selected rows. We cannot track selected keys
-   * instead because we might end up in an inconsistent state where we render a
-   * subset of a list with duplicate values, styling a value in the subset but
-   * not styling the duplicate value outside of the subset.
-   */
-  private final Set<Integer> selectedRows = new HashSet<Integer>();
+  private int pendingStateLoop = 0;
 
   private HandlerRegistration selectionHandler;
   private SelectionModel<? super T> selectionModel;
+
+  /**
+   * The current state of the presenter reflected in the view. We intentionally
+   * use the interface, which only has getters, to ensure that we do not
+   * accidently modify the current state.
+   */
+  private State<T> state;
+
   private final View<T> view;
 
   /**
    * Construct a new {@link HasDataPresenter}.
-   *
+   * 
    * @param display the display that is being presented
    * @param view the view implementation
    * @param pageSize the default page size
@@ -302,8 +430,8 @@
       ProvidesKey<T> keyProvider) {
     this.display = display;
     this.view = view;
-    this.pageSize = pageSize;
     this.keyProvider = keyProvider;
+    this.state = new DefaultState<T>(pageSize);
   }
 
   public HandlerRegistration addRangeChangeHandler(
@@ -317,6 +445,15 @@
   }
 
   /**
+   * Clear the row value associated with the keyboard selected row.
+   */
+  public void clearKeyboardSelectedRowValue() {
+    if (getKeyboardSelectedRowValue() != null) {
+      ensurePendingState().keyboardSelectedRowValue = null;
+    }
+  }
+
+  /**
    * Clear the {@link SelectionModel} without updating the view.
    */
   public void clearSelectionModel() {
@@ -336,13 +473,28 @@
   }
 
   /**
+   * Flush pending changes to the view.
+   */
+  public void flush() {
+    /*
+     * resolvePendingState can exit early user code applied more pending state,
+     * so we need to loop until we are sure that the pending state is clear. If
+     * the user calls this method while resolving pending state, then do not
+     * attempt to resolve pending state again.
+     */
+    while (pendingStateCommand != null && !isResolvingState) {
+      resolvePendingState();
+    }
+  }
+
+  /**
    * Get the current page size. This is usually the page size, but can be less
    * if the data size cannot fill the current page.
-   *
+   * 
    * @return the size of the current page
    */
   public int getCurrentPageSize() {
-    return Math.min(pageSize, rowCount - pageStart);
+    return Math.min(getPageSize(), getRowCount() - getPageStart());
   }
 
   public KeyboardPagingPolicy getKeyboardPagingPolicy() {
@@ -351,12 +503,34 @@
 
   /**
    * Get the index of the keyboard selected row relative to the page start.
-   *
+   * 
    * @return the row index, or -1 if disabled
    */
   public int getKeyboardSelectedRow() {
     return KeyboardSelectionPolicy.DISABLED == keyboardSelectionPolicy ? -1
-        : keyboardSelectedRow;
+        : getCurrentState().getKeyboardSelectedRow();
+  }
+
+  /**
+   * Get the index of the keyboard selected row relative to the page start as it
+   * appears in the view, regardless of whether or not there is a pending
+   * change.
+   * 
+   * @return the row index, or -1 if disabled
+   */
+  public int getKeyboardSelectedRowInView() {
+    return KeyboardSelectionPolicy.DISABLED == keyboardSelectionPolicy ? -1
+        : state.getKeyboardSelectedRow();
+  }
+
+  /**
+   * Get the value that the user selected.
+   * 
+   * @return the value, or null if a value was not selected
+   */
+  public T getKeyboardSelectedRowValue() {
+    return KeyboardSelectionPolicy.DISABLED == keyboardSelectionPolicy ? null
+        : getCurrentState().getKeyboardSelectedRowValue();
   }
 
   public KeyboardSelectionPolicy getKeyboardSelectionPolicy() {
@@ -369,22 +543,30 @@
 
   /**
    * Get the overall data size.
-   *
+   * 
    * @return the data size
    */
   public int getRowCount() {
-    return rowCount;
+    return getCurrentState().getRowCount();
   }
 
   /**
-   * Get the list of data within the current range. The 0th index corresponds to
-   * the first value on the page. The data may not be complete or may contain
-   * null values.
-   *
-   * @return the list of data for the current page
+   * Get the size of the list of row data.
+   * 
+   * @return the size of the row data
    */
-  public List<T> getRowData() {
-    return rowData;
+  public int getRowDataSize() {
+    return getCurrentState().getRowDataSize();
+  }
+
+  /**
+   * Get a value from the row data.
+   * 
+   * @param the index of the row data
+   * @return the value at the specified index
+   */
+  public T getRowDataValue(int index) {
+    return getCurrentState().getRowDataValue(index);
   }
 
   public SelectionModel<? super T> getSelectionModel() {
@@ -395,21 +577,21 @@
    * Return the range of data being displayed.
    */
   public Range getVisibleRange() {
-    return new Range(pageStart, pageSize);
+    return new Range(getPageStart(), getPageSize());
   }
 
   /**
    * Check if the next call to {@link #keyboardNext()} would succeed.
-   *
+   * 
    * @return true if there is another row accessible by the keyboard
    */
   public boolean hasKeyboardNext() {
     if (KeyboardSelectionPolicy.DISABLED == keyboardSelectionPolicy) {
       return false;
-    } else if (keyboardSelectedRow < rowData.size() - 1) {
+    } else if (getKeyboardSelectedRow() < getRowDataSize() - 1) {
       return true;
     } else if (!keyboardPagingPolicy.isLimitedToRange()
-        && (keyboardSelectedRow + pageStart < rowCount - 1 || !rowCountIsExact)) {
+        && (getKeyboardSelectedRow() + getPageStart() < getRowCount() - 1 || !isRowCountExact())) {
       return true;
     }
     return false;
@@ -417,22 +599,33 @@
 
   /**
    * Check if the next call to {@link #keyboardPrevious()} would succeed.
-   *
+   * 
    * @return true if there is a previous row accessible by the keyboard
    */
   public boolean hasKeyboardPrev() {
     if (KeyboardSelectionPolicy.DISABLED == keyboardSelectionPolicy) {
       return false;
-    } else if (keyboardSelectedRow > 0) {
+    } else if (getKeyboardSelectedRow() > 0) {
       return true;
-    } else if (!keyboardPagingPolicy.isLimitedToRange() && pageStart > 0) {
+    } else if (!keyboardPagingPolicy.isLimitedToRange() && getPageStart() > 0) {
       return true;
     }
     return false;
   }
 
+  /**
+   * Check whether or not there is a pending state. If there is a pending state,
+   * views might skip DOM updates and wait for the new data to be rendered when
+   * the pending state is resolved.
+   * 
+   * @return true if there is a pending state, false if not
+   */
+  public boolean hasPendingState() {
+    return pendingState != null;
+  }
+
   public boolean isRowCountExact() {
-    return rowCountIsExact;
+    return getCurrentState().isRowCountExact();
   }
 
   /**
@@ -440,7 +633,7 @@
    */
   public void keyboardEnd() {
     if (!keyboardPagingPolicy.isLimitedToRange()) {
-      setKeyboardSelectedRow(rowCount - 1, true);
+      setKeyboardSelectedRow(getRowCount() - 1, true);
     }
   }
 
@@ -449,7 +642,7 @@
    */
   public void keyboardHome() {
     if (!keyboardPagingPolicy.isLimitedToRange()) {
-      setKeyboardSelectedRow(-pageStart, true);
+      setKeyboardSelectedRow(-getPageStart(), true);
     }
   }
 
@@ -458,7 +651,7 @@
    */
   public void keyboardNext() {
     if (hasKeyboardNext()) {
-      setKeyboardSelectedRow(keyboardSelectedRow + 1, true);
+      setKeyboardSelectedRow(getKeyboardSelectedRow() + 1, true);
     }
   }
 
@@ -468,9 +661,9 @@
   public void keyboardNextPage() {
     if (KeyboardPagingPolicy.CHANGE_PAGE == keyboardPagingPolicy) {
       // 0th index of next page.
-      setKeyboardSelectedRow(pageSize, true);
+      setKeyboardSelectedRow(getPageSize(), true);
     } else if (KeyboardPagingPolicy.INCREASE_RANGE == keyboardPagingPolicy) {
-      setKeyboardSelectedRow(keyboardSelectedRow + PAGE_INCREMENT, true);
+      setKeyboardSelectedRow(getKeyboardSelectedRow() + PAGE_INCREMENT, true);
     }
   }
 
@@ -479,7 +672,7 @@
    */
   public void keyboardPrev() {
     if (hasKeyboardPrev()) {
-      setKeyboardSelectedRow(keyboardSelectedRow - 1, true);
+      setKeyboardSelectedRow(getKeyboardSelectedRow() - 1, true);
     }
   }
 
@@ -489,9 +682,9 @@
   public void keyboardPrevPage() {
     if (KeyboardPagingPolicy.CHANGE_PAGE == keyboardPagingPolicy) {
       // 0th index of previous page.
-      setKeyboardSelectedRow(-pageSize, true);
+      setKeyboardSelectedRow(-getPageSize(), true);
     } else if (KeyboardPagingPolicy.INCREASE_RANGE == keyboardPagingPolicy) {
-      setKeyboardSelectedRow(keyboardSelectedRow - PAGE_INCREMENT, true);
+      setKeyboardSelectedRow(getKeyboardSelectedRow() - PAGE_INCREMENT, true);
     }
   }
 
@@ -499,10 +692,11 @@
    * Toggle selection of the current keyboard row in the {@link SelectionModel}.
    */
   public void keyboardToggleSelect() {
+    int keyboardSelectedRow = getKeyboardSelectedRow();
     if (KeyboardSelectionPolicy.ENABLED == keyboardSelectionPolicy
         && selectionModel != null && keyboardSelectedRow >= 0
-        && keyboardSelectedRow < rowData.size()) {
-      T value = rowData.get(keyboardSelectedRow);
+        && keyboardSelectedRow < getRowDataSize()) {
+      T value = getRowDataValue(keyboardSelectedRow);
       if (value != null) {
         selectionModel.setSelected(value, !selectionModel.isSelected(value));
       }
@@ -514,7 +708,7 @@
    */
   public void redraw() {
     lastContents = null;
-    setRowData(pageStart, rowData);
+    ensurePendingState().redrawRequired = true;
   }
 
   public void setKeyboardPagingPolicy(KeyboardPagingPolicy policy) {
@@ -526,7 +720,7 @@
 
   /**
    * Set the row index of the keyboard selected element.
-   *
+   * 
    * @param index the row index
    * @param stealFocus true to steal focus
    */
@@ -535,24 +729,16 @@
     if (KeyboardSelectionPolicy.DISABLED == keyboardSelectionPolicy) {
       return;
     }
-    boolean isBound = KeyboardSelectionPolicy.BOUND_TO_SELECTION == keyboardSelectionPolicy;
-
-    // Deselect the old index.
-    if (keyboardSelectedRow >= 0 && keyboardSelectedRow < view.getChildCount()) {
-      view.setKeyboardSelected(keyboardSelectedRow, false, false);
-      if (isBound) {
-        deselectKeyboardValue();
-      }
-    }
 
     // Trim to within bounds.
+    int pageStart = getPageStart();
+    int pageSize = getPageSize();
+    int rowCount = getRowCount();
     int absIndex = pageStart + index;
-    if (absIndex < 0) {
-      absIndex = 0;
-    } else if (absIndex >= rowCount && rowCountIsExact) {
+    if (absIndex >= rowCount && isRowCountExact()) {
       absIndex = rowCount - 1;
     }
-    index = absIndex - pageStart;
+    index = Math.max(0, absIndex) - pageStart;
     if (keyboardPagingPolicy.isLimitedToRange()) {
       index = Math.max(0, Math.min(index, pageSize - 1));
     }
@@ -560,13 +746,15 @@
     // Select the new index.
     int newPageStart = pageStart;
     int newPageSize = pageSize;
-    keyboardSelectedRow = 0;
+    PendingState<T> pending = ensurePendingState();
+    pending.keyboardSelectedRow = 0;
+    pending.keyboardSelectedRowValue = null;
+    pending.keyboardSelectedRowChanged = true;
     if (index >= 0 && index < pageSize) {
-      keyboardSelectedRow = index;
-      if (isBound) {
-        selectKeyboardValue(index);
-      }
-      view.setKeyboardSelected(index, true, stealFocus);
+      pending.keyboardSelectedRow = index;
+      pending.keyboardSelectedRowValue = index < pending.getRowDataSize()
+          ? ensurePendingState().getRowDataValue(index) : null;
+      pending.keyboardStealFocus = stealFocus;
       return;
     } else if (KeyboardPagingPolicy.CHANGE_PAGE == keyboardPagingPolicy) {
       // Go to previous page.
@@ -607,8 +795,7 @@
 
     // Update the range if it changed.
     if (newPageStart != pageStart || newPageSize != pageSize) {
-      deselectKeyboardValue();
-      keyboardSelectedRow = index;
+      pending.keyboardSelectedRow = index;
       setVisibleRange(new Range(newPageStart, newPageSize), false, false);
     }
   }
@@ -630,25 +817,17 @@
   }
 
   public void setRowCount(int count, boolean isExact) {
-    if (count == this.rowCount && isExact == this.rowCountIsExact) {
+    if (count == getRowCount() && isExact == isRowCountExact()) {
       return;
     }
-    this.rowCount = count;
-    this.rowCountIsExact = isExact;
-    updateLoadingState();
+    ensurePendingState().rowCount = count;
+    ensurePendingState().rowCountIsExact = isExact;
 
-    // Update the keyboardSelectedRow.
-    if (keyboardSelectedRow >= count) {
-      keyboardSelectedRow = Math.max(0, count - 1);
-    }
-
-    // Redraw the current page if it is affected by the new data size.
-    if (updateCachedData()) {
-      redraw();
-    }
+    // Update the cached data.
+    updateCachedData();
 
     // Update the pager.
-    RowCountChangeEvent.fire(display, count, rowCountIsExact);
+    RowCountChangeEvent.fire(display, count, isExact);
   }
 
   public void setRowData(int start, List<? extends T> values) {
@@ -656,7 +835,8 @@
     int valuesEnd = start + valuesLength;
 
     // Calculate the bounded start (inclusive) and end index (exclusive).
-    int pageEnd = pageStart + pageSize;
+    int pageStart = getPageStart();
+    int pageEnd = getPageStart() + getPageSize();
     int boundedStart = Math.max(start, pageStart);
     int boundedEnd = Math.min(valuesEnd, pageEnd);
     if (start != pageStart && boundedStart >= boundedEnd) {
@@ -665,115 +845,30 @@
       return;
     }
 
-    // The data size must be at least as large as the data.
-    if (valuesEnd > rowCount) {
-      rowCount = valuesEnd;
-      RowCountChangeEvent.fire(display, rowCount, rowCountIsExact);
-    }
-
     // Create placeholders up to the specified index.
-    int cacheOffset = Math.max(0, boundedStart - pageStart - rowData.size());
+    PendingState<T> pending = ensurePendingState();
+    int cacheOffset = Math.max(0, boundedStart - pageStart - getRowDataSize());
     for (int i = 0; i < cacheOffset; i++) {
-      rowData.add(null);
-    }
-
-    // If the keyboard selected row is within the data set, clear it out. If the
-    // key still exists, it will be reset below at its new index.
-    Object keyboardSelectedKey = null;
-    int keyboardSelectedAbsoluteRow = pageStart + keyboardSelectedRow;
-    boolean keyboardSelectedInRange = false;
-    boolean keyboardSelectedStillExists = false;
-    if (keyboardSelectedAbsoluteRow >= boundedStart
-        && keyboardSelectedAbsoluteRow < boundedEnd) {
-      keyboardSelectedInRange = true;
-
-      // If the value is null, then we will select whatever value is at the
-      // selected row.
-      if (keyboardSelectedRowValue != null) {
-        keyboardSelectedKey = getRowValueKey(keyboardSelectedRowValue);
-        keyboardSelectedRow = 0; // Will be set to a non-negative number later.
-      }
+      pending.rowData.add(null);
     }
 
     // Insert the new values into the data array.
     for (int i = boundedStart; i < boundedEnd; i++) {
       T value = values.get(i - start);
       int dataIndex = i - pageStart;
-      if (dataIndex < rowData.size()) {
-        rowData.set(dataIndex, value);
+      if (dataIndex < getRowDataSize()) {
+        pending.rowData.set(dataIndex, value);
       } else {
-        rowData.add(value);
-      }
-
-      // Update our local cache of selected rows.
-      if (selectionModel != null) {
-        if (value != null && selectionModel.isSelected(value)) {
-          selectedRows.add(i);
-        } else {
-          selectedRows.remove(i);
-        }
-      }
-
-      // Update the keyboard selected index.
-      if (keyboardSelectedKey != null && value != null
-          && keyboardSelectedKey.equals(getRowValueKey(value))) {
-        keyboardSelectedRow = i - pageStart;
-        keyboardSelectedStillExists = true;
+        pending.rowData.add(value);
       }
     }
 
-    // Construct a run of elements within the range of the data and the page.
-    // boundedStart = start index of the data to replace.
-    // boundedSize = the number of items to replace.
-    boundedStart = pageStartChangedSinceRender ? pageStart : boundedStart;
-    boundedStart -= cacheOffset;
-    List<T> boundedValues = rowData.subList(boundedStart - pageStart,
-        boundedEnd - pageStart);
-    int boundedSize = boundedValues.size();
-    SafeHtmlBuilder sb = new SafeHtmlBuilder();
-    view.render(sb, boundedValues, boundedStart, selectionModel);
+    // Remember the range that has been replaced.
+    pending.replaceRange(boundedStart - cacheOffset, boundedEnd);
 
-    // Update the loading state.
-    updateLoadingState();
-
-    // Replace the DOM elements with the new rendered cells.
-    int childCount = view.getChildCount();
-    if (boundedStart == pageStart
-        && (boundedSize >= childCount || boundedSize >= getCurrentPageSize() || rowData.size() < childCount)) {
-      // If the contents have not changed, we're done.
-      SafeHtml newContents = sb.toSafeHtml();
-      if (!newContents.equals(lastContents)) {
-        lastContents = newContents;
-        view.replaceAllChildren(boundedValues, newContents);
-      }
-
-      // Allow the view to reestablish focus after being re-rendered.
-      view.resetFocus();
-    } else {
-      lastContents = null;
-      view.replaceChildren(boundedValues, boundedStart - pageStart,
-          sb.toSafeHtml());
-
-      // Only reset focus if needed.
-      if (keyboardSelectedStillExists) {
-        view.resetFocus();
-      }
-    }
-
-    // Reset the pageStartChanged boolean.
-    pageStartChangedSinceRender = false;
-
-    // Update the keyboard selected value.
-    if (keyboardSelectedInRange && !keyboardSelectedStillExists) {
-      if (keyboardSelectedKey != null) {
-        // We had a value, but its lost.
-        deselectKeyboardValue();
-      }
-
-      // Select the selected row based off the row index.
-      if (KeyboardSelectionPolicy.BOUND_TO_SELECTION == keyboardSelectionPolicy) {
-        selectKeyboardValue(keyboardSelectedRow);
-      }
+    // Fire a row count change event after updating the data.
+    if (valuesEnd > getRowCount()) {
+      setRowCount(valuesEnd, isRowCountExact());
     }
   }
 
@@ -803,55 +898,461 @@
     if (selectionModel != null) {
       selectionHandler = selectionModel.addSelectionChangeHandler(new SelectionChangeEvent.Handler() {
         public void onSelectionChange(SelectionChangeEvent event) {
-          updateSelection();
+          // Ensure that we resolve selection.
+          ensurePendingState();
         }
       });
     }
 
     // Update the current selection state based on the new model.
-    updateSelection();
+    ensurePendingState();
   }
 
   /**
-   * Deselect the keyboard selected value.
+   * Combine the modified row indexes into as many as two {@link Range}s,
+   * optimizing to have the fewest unmodified rows within the ranges. Using two
+   * ranges covers the most common use cases of selecting one row, selecting a
+   * range, moving selection from one row to another, or moving keyboard
+   * selection.
+   * 
+   * Visible for testing.
+   * 
+   * @param modifiedRows the indexes of modified rows
+   * @return up to two ranges that encompass the modified rows
    */
-  private void deselectKeyboardValue() {
-    if (selectionModel != null && keyboardSelectedRowValue != null) {
-      T curValue = keyboardSelectedRowValue;
-      keyboardSelectedRow = 0;
-      keyboardSelectedRowValue = null;
-      selectionModel.setSelected(curValue, false);
+  List<Range> calculateModifiedRanges(TreeSet<Integer> modifiedRows,
+      int pageStart, int pageEnd) {
+    int rangeStart0 = -1;
+    int rangeEnd0 = -1;
+    int rangeStart1 = -1;
+    int rangeEnd1 = -1;
+    int maxDiff = 0;
+    for (int index : modifiedRows) {
+      if (index < pageStart || index >= pageEnd) {
+        // The index is out of range of the current page.
+        continue;
+      } else if (rangeStart0 == -1) {
+        // Range0 defaults to the first index.
+        rangeStart0 = index;
+        rangeEnd0 = index;
+      } else if (rangeStart1 == -1) {
+        // Range1 defaults to the second index.
+        maxDiff = index - rangeEnd0;
+        rangeStart1 = index;
+        rangeEnd1 = index;
+      } else {
+        int diff = index - rangeEnd1;
+        if (diff > maxDiff) {
+          // Move the old range1 onto range0 and start range1 from this index.
+          rangeEnd0 = rangeEnd1;
+          rangeStart1 = index;
+          rangeEnd1 = index;
+          maxDiff = diff;
+        } else {
+          // Add this index to range1.
+          rangeEnd1 = index;
+        }
+      }
     }
+
+    // Convert the range ends to exclusive indexes for calculations.
+    rangeEnd0 += 1;
+    rangeEnd1 += 1;
+
+    // Combine the ranges if they are continuous.
+    if (rangeStart1 == rangeEnd0) {
+      rangeEnd0 = rangeEnd1;
+      rangeStart1 = -1;
+      rangeEnd1 = -1;
+    }
+
+    // Return the ranges.
+    List<Range> toRet = new ArrayList<Range>();
+    if (rangeStart0 != -1) {
+      int rangeLength0 = rangeEnd0 - rangeStart0;
+      toRet.add(new Range(rangeStart0, rangeLength0));
+    }
+    if (rangeStart1 != -1) {
+      int rangeLength1 = rangeEnd1 - rangeStart1;
+      toRet.add(new Range(rangeStart1, rangeLength1));
+    }
+    return toRet;
+  }
+
+  /**
+   * Ensure that a pending {@link DefaultState} exists and return it.
+   * 
+   * @return the pending state
+   */
+  private PendingState<T> ensurePendingState() {
+    // Create the pending state if needed.
+    if (pendingState == null) {
+      pendingState = new PendingState<T>(state);
+    }
+
+    /*
+     * Schedule a command to resolve the pending state. If a command is already
+     * scheduled, we reschedule a new one to ensure that it happens after any
+     * existing finally commands (such as SelectionModel commands).
+     */
+    pendingStateCommand = new ScheduledCommand() {
+      public void execute() {
+        // Verify that this command was the last one scheduled.
+        if (pendingStateCommand == this) {
+          resolvePendingState();
+        }
+      }
+    };
+    Scheduler.get().scheduleFinally(pendingStateCommand);
+
+    // Return the pending state.
+    return pendingState;
+  }
+
+  /**
+   * Find the index within the {@link State} of the best match for the specified
+   * row value. The best match is a row value with the same key, closest to the
+   * initial index.
+   * 
+   * @param state the state to search
+   * @param value the value to find
+   * @param initialIndex the initial index of the value
+   * @return the best match index, or -1 if not found
+   */
+  private int findIndexOfBestMatch(State<T> state, T value, int initialIndex) {
+    // Get the key for the value.
+    Object key = getRowValueKey(value);
+    if (key == null) {
+      return -1;
+    }
+
+    int bestMatchIndex = -1;
+    int bestMatchDiff = Integer.MAX_VALUE;
+    int rowDataCount = state.getRowDataSize();
+    for (int i = 0; i < rowDataCount; i++) {
+      T curValue = state.getRowDataValue(i);
+      Object curKey = getRowValueKey(curValue);
+      if (key.equals(curKey)) {
+        int diff = Math.abs(initialIndex - i);
+        if (diff < bestMatchDiff) {
+          bestMatchIndex = i;
+          bestMatchDiff = diff;
+        }
+      }
+    }
+    return bestMatchIndex;
+  }
+
+  /**
+   * Get the current state of the presenter.
+   * 
+   * @return the pending state if one exists, otherwise the state
+   */
+  private State<T> getCurrentState() {
+    return pendingState == null ? state : pendingState;
+  }
+
+  private int getPageSize() {
+    return getCurrentState().getPageSize();
+  }
+
+  private int getPageStart() {
+    return getCurrentState().getPageStart();
   }
 
   /**
    * Get the key for the specified row value.
-   *
+   * 
    * @param rowValue the row value
    * @return the key
    */
   private Object getRowValueKey(T rowValue) {
-    return keyProvider == null ? rowValue : keyProvider.getKey(rowValue);
+    return (keyProvider == null || rowValue == null) ? rowValue
+        : keyProvider.getKey(rowValue);
   }
 
   /**
-   * Select the value at the keyboard selected row.
-   *
-   * @param row the row index
+   * Resolve the pending state and push updates to the view.
    */
-  private void selectKeyboardValue(int row) {
-    if (selectionModel != null && row >= 0 && row < rowData.size()) {
-      keyboardSelectedRowValue = rowData.get(row);
-      if (keyboardSelectedRowValue != null) {
-        selectionModel.setSelected(keyboardSelectedRowValue, true);
+  private void resolvePendingState() {
+    pendingStateCommand = null;
+
+    // Early exit if there is no pending state.
+    if (pendingState == null) {
+      pendingStateLoop = 0;
+      return;
+    }
+
+    /*
+     * Check for an infinite loop. This can happen if user code accessed in this
+     * method modifies the pending state and flushes changes.
+     */
+    pendingStateLoop++;
+    if (pendingStateLoop > LOOP_MAXIMUM) {
+      pendingStateLoop = 0; // Let user code handle exception and try again.
+      throw new IllegalStateException(
+          "A possible infinite loop has been detected in a Cell Widget. This "
+              + "usually happens when your SelectionModel triggers a "
+              + "SelectionChangeEvent when SelectionModel.isSelection() is "
+              + "called, which causes the table to redraw continuously.");
+    }
+
+    /*
+     * Check for conflicting state resolution code. This can happen if the
+     * View's render methods modify the view and flush the pending state.
+     */
+    if (isResolvingState) {
+      throw new IllegalStateException(
+          "The Cell Widget is attempting to render itself within the render "
+              + "loop. This usually happens when your render code modifies the "
+              + "state of the Cell Widget then accesses data or elements "
+              + "within the Widget.");
+    }
+    isResolvingState = true;
+
+    // Keep track of the absolute indexes of modified rows.
+    TreeSet<Integer> modifiedRows = new TreeSet<Integer>();
+
+    // Get the values used for calculations.
+    State<T> oldState = state;
+    PendingState<T> pending = pendingState;
+    int pageStart = pending.getPageStart();
+    int pageSize = pending.getPageSize();
+    int pageEnd = pageStart + pageSize;
+    int rowDataCount = pending.getRowDataSize();
+
+    /*
+     * Resolve keyboard selection. If the row value still exists, use its index.
+     * If the row value exists in multiple places, use the closest index. If the
+     * row value not longer exists, use the current index.
+     */
+    pending.keyboardSelectedRow = Math.max(0,
+        Math.min(pending.keyboardSelectedRow, rowDataCount - 1));
+    if (KeyboardSelectionPolicy.DISABLED == keyboardSelectionPolicy) {
+      // Clear the keyboard selected state.
+      pending.keyboardSelectedRow = 0;
+      pending.keyboardSelectedRowValue = null;
+    } else if (pending.keyboardSelectedRowChanged) {
+      // Choose the row value based on the index.
+      pending.keyboardSelectedRowValue = rowDataCount > 0
+          ? pending.getRowDataValue(pending.keyboardSelectedRow) : null;
+    } else if (pending.keyboardSelectedRowValue != null) {
+      // Choose the index based on the row value.
+      int bestMatchIndex = findIndexOfBestMatch(pending,
+          pending.keyboardSelectedRowValue, pending.keyboardSelectedRow);
+      if (bestMatchIndex >= 0) {
+        // A match was found.
+        pending.keyboardSelectedRow = bestMatchIndex;
+        pending.keyboardSelectedRowValue = rowDataCount > 0
+            ? pending.getRowDataValue(pending.keyboardSelectedRow) : null;
+      } else {
+        // No match was found, so reset to 0.
+        pending.keyboardSelectedRow = 0;
+        pending.keyboardSelectedRowValue = null;
       }
     }
+
+    /*
+     * Update the SelectionModel based on the keyboard selected value. This must
+     * happen before we read the selection state.
+     */
+    if (KeyboardSelectionPolicy.BOUND_TO_SELECTION == keyboardSelectionPolicy
+        && selectionModel != null) {
+      T oldValue = oldState.getRowDataSize() > 0
+          ? oldState.getRowDataValue(oldState.getKeyboardSelectedRow()) : null;
+      Object oldKey = getRowValueKey(oldValue);
+      T newValue = rowDataCount > 0
+          ? pending.getRowDataValue(pending.getKeyboardSelectedRow()) : null;
+      Object newKey = getRowValueKey(newValue);
+      if ((oldKey == null) ? newKey != null : !oldKey.equals(newKey)) {
+        // Deselect the old value.
+        if (oldValue != null && selectionModel.isSelected(oldValue)) {
+          selectionModel.setSelected(oldValue, false);
+        }
+
+        // Select the new value.
+        if (newValue != null && !selectionModel.isSelected(newValue)) {
+          selectionModel.setSelected(newValue, true);
+        }
+      }
+    }
+
+    // If the keyboard row changes, add it to the modified set.
+    boolean keyboardRowChanged = pending.keyboardSelectedRowChanged
+        || (oldState.getKeyboardSelectedRow() != pending.keyboardSelectedRow)
+        || (oldState.getKeyboardSelectedRowValue() == null && pending.keyboardSelectedRowValue != null);
+
+    /*
+     * Resolve selection. Check the selection status of all row values in the
+     * pending state and compare them to the status in the old state. If we know
+     * longer have a SelectionModel but had selected rows, we still need to
+     * update the rows.
+     */
+    for (int i = pageStart; i < pageStart + rowDataCount; i++) {
+      // Check the new selection state.
+      T rowValue = pending.getRowDataValue(i - pageStart);
+      boolean isSelected = (rowValue != null && selectionModel != null && selectionModel.isSelected(rowValue));
+
+      // Compare to the old selection state.
+      boolean wasSelected = oldState.isRowSelected(i);
+      if (isSelected) {
+        pending.selectedRows.add(i);
+        if (!wasSelected) {
+          modifiedRows.add(i);
+        }
+      } else if (wasSelected) {
+        modifiedRows.add(i);
+      }
+    }
+
+    /*
+     * We called methods in user code that could modify the view, so early exit
+     * if there is a new pending state waiting to be resolved.
+     */
+    if (pendingStateCommand != null) {
+      isResolvingState = false;
+      return;
+    }
+    pendingStateLoop = 0;
+
+    // Swap the states.
+    state = pendingState;
+    pendingState = null;
+
+    // Add the replaced ranges as modified rows.
+    boolean replacedEmptyRange = false;
+    for (Range replacedRange : pending.replacedRanges) {
+      int start = replacedRange.getStart();
+      int length = replacedRange.getLength();
+      // If the user set an empty range, pass it through to the view.
+      if (length == 0) {
+        replacedEmptyRange = true;
+      }
+      for (int i = start; i < start + length; i++) {
+        modifiedRows.add(i);
+      }
+    }
+
+    // Add keyboard rows to modified rows if we are going to render anyway.
+    if (modifiedRows.size() > 0 && keyboardRowChanged) {
+      modifiedRows.add(oldState.getKeyboardSelectedRow());
+      modifiedRows.add(pending.keyboardSelectedRow);
+    }
+
+    // Calculate the modified ranges.
+    List<Range> modifiedRanges = calculateModifiedRanges(modifiedRows,
+        pageStart, pageEnd);
+    Range range0 = modifiedRanges.size() > 0 ? modifiedRanges.get(0) : null;
+    Range range1 = modifiedRanges.size() > 1 ? modifiedRanges.get(1) : null;
+    int replaceDiff = 0; // The total number of rows to replace.
+    for (Range range : modifiedRanges) {
+      replaceDiff += range.getLength();
+    }
+
+    /*
+     * Check the various conditions that require redraw.
+     */
+    int oldPageStart = oldState.getPageStart();
+    int oldPageSize = oldState.getPageSize();
+    int oldRowDataCount = oldState.getRowDataSize();
+    boolean redrawRequired = pending.redrawRequired;
+    if (pageStart != oldPageStart) {
+      // Redraw if pageStart changes.
+      redrawRequired = true;
+    } else if (rowDataCount < oldRowDataCount) {
+      // Redraw if we have trimmed the row data.
+      redrawRequired = true;
+    } else if (range1 == null && range0 != null
+        && range0.getStart() == pageStart
+        && (replaceDiff >= oldRowDataCount || replaceDiff > oldPageSize)) {
+      // Redraw if the new data completely overlaps the old data.
+      redrawRequired = true;
+    } else if (replaceDiff >= REDRAW_MINIMUM
+        && replaceDiff > REDRAW_THRESHOLD * oldRowDataCount) {
+      /*
+       * Redraw if the number of modified rows represents a large portion of the
+       * view, defined as greater than 30% of the rows (minimum of 5).
+       */
+      redrawRequired = true;
+    } else if (replacedEmptyRange && oldRowDataCount == 0) {
+      /*
+       * If the user replaced an empty range, pass it to the view. This is a
+       * useful edge case that provides consistency in the way data is pushed to
+       * the view.
+       */
+      redrawRequired = true;
+    }
+
+    // Update the loading state in the view.
+    updateLoadingState();
+
+    /*
+     * Push changes to the view.
+     */
+    if (redrawRequired) {
+      // Redraw the entire content.
+      SafeHtmlBuilder sb = new SafeHtmlBuilder();
+      view.render(sb, pending.rowData, pending.pageStart, selectionModel);
+      SafeHtml newContents = sb.toSafeHtml();
+      if (!newContents.equals(lastContents)) {
+        lastContents = newContents;
+        view.replaceAllChildren(pending.rowData, newContents,
+            pending.keyboardStealFocus);
+      }
+      view.resetFocus();
+    } else if (range0 != null) {
+      // Replace specific rows.
+      lastContents = null;
+
+      // Replace range0.
+      {
+        int absStart = range0.getStart();
+        int relStart = absStart - pageStart;
+        SafeHtmlBuilder sb = new SafeHtmlBuilder();
+        List<T> replaceValues = pending.rowData.subList(relStart, relStart
+            + range0.getLength());
+        view.render(sb, replaceValues, absStart, selectionModel);
+        view.replaceChildren(replaceValues, relStart, sb.toSafeHtml(),
+            pending.keyboardStealFocus);
+      }
+
+      // Replace range1 if it exists.
+      if (range1 != null) {
+        int absStart = range1.getStart();
+        int relStart = absStart - pageStart;
+        SafeHtmlBuilder sb = new SafeHtmlBuilder();
+        List<T> replaceValues = pending.rowData.subList(relStart, relStart
+            + range1.getLength());
+        view.render(sb, replaceValues, absStart, selectionModel);
+        view.replaceChildren(replaceValues, relStart, sb.toSafeHtml(),
+            pending.keyboardStealFocus);
+      }
+
+      view.resetFocus();
+    } else if (keyboardRowChanged) {
+      // Update the keyboard selected rows without redrawing.
+      // Deselect the old keyboard row.
+      int oldSelectedRow = oldState.getKeyboardSelectedRow();
+      if (oldSelectedRow >= 0 && oldSelectedRow < rowDataCount) {
+        view.setKeyboardSelected(oldSelectedRow, false, false);
+      }
+
+      // Select the new keyboard row.
+      int newSelectedRow = pending.getKeyboardSelectedRow();
+      if (newSelectedRow >= 0 && newSelectedRow < rowDataCount) {
+        view.setKeyboardSelected(newSelectedRow, true,
+            pending.keyboardStealFocus);
+      }
+    }
+
+    // We are done resolving state.
+    isResolvingState = false;
   }
 
   /**
    * Set the visible {@link Range}, optionally clearing data and/or firing a
    * {@link RangeChangeEvent}.
-   *
+   * 
    * @param range the new {@link Range}
    * @param clearData true to clear all data
    * @param forceRangeChangeEvent true to force a {@link RangeChangeEvent}
@@ -860,64 +1361,69 @@
       boolean forceRangeChangeEvent) {
     final int start = range.getStart();
     final int length = range.getLength();
+    if (start < 0) {
+      throw new IllegalArgumentException("Range start cannot be less than 0");
+    }
     if (length < 0) {
-      throw new IllegalArgumentException("Range length cannot be less than 1");
+      throw new IllegalArgumentException("Range length cannot be less than 0");
     }
 
     // Update the page start.
+    final int pageStart = getPageStart();
+    final int pageSize = getPageSize();
     final boolean pageStartChanged = (pageStart != start);
     if (pageStartChanged) {
+      PendingState<T> pending = ensurePendingState();
+
       // Trim the data if we aren't clearing it.
       if (!clearData) {
         if (start > pageStart) {
           int increase = start - pageStart;
-          if (rowData.size() > increase) {
+          if (getRowDataSize() > increase) {
             // Remove the data we no longer need.
             for (int i = 0; i < increase; i++) {
-              rowData.remove(0);
+              pending.rowData.remove(0);
             }
           } else {
             // We have no overlapping data, so just clear it.
-            rowData.clear();
+            pending.rowData.clear();
           }
         } else {
           int decrease = pageStart - start;
-          if ((rowData.size() > 0) && (decrease < pageSize)) {
+          if ((getRowDataSize() > 0) && (decrease < pageSize)) {
             // Insert null data at the beginning.
             for (int i = 0; i < decrease; i++) {
-              rowData.add(0, null);
+              pending.rowData.add(0, null);
             }
+
+            // Remember the inserted range because we might return to the same
+            // pageStart in this event loop, which means we won't do a full
+            // redraw, but still need to replace the inserted nulls in the view.
+            pending.replaceRange(start, start + decrease);
           } else {
             // We have no overlapping data, so just clear it.
-            rowData.clear();
+            pending.rowData.clear();
           }
         }
       }
 
       // Update the page start.
-      pageStart = start;
-      pageStartChangedSinceRender = true;
+      pending.pageStart = start;
     }
 
     // Update the page size.
     final boolean pageSizeChanged = (pageSize != length);
     if (pageSizeChanged) {
-      pageSize = length;
+      ensurePendingState().pageSize = length;
     }
 
     // Clear the data.
     if (clearData) {
-      rowData.clear();
-      selectedRows.clear();
+      ensurePendingState().rowData.clear();
     }
 
-    // Update the loading state.
-    updateLoadingState();
-
-    // Redraw with the existing data.
-    if (pageStartChanged || clearData || updateCachedData()) {
-      redraw();
-    }
+    // Trim the row values if needed.
+    updateCachedData();
 
     // Update the pager and data source if the range changed.
     if (pageStartChanged || pageSizeChanged || forceRangeChangeEvent) {
@@ -927,30 +1433,25 @@
 
   /**
    * Ensure that the cached data is consistent with the data size.
-   *
-   * @return true if the data was updated, false if not
    */
-  private boolean updateCachedData() {
-    boolean updated = false;
+  private void updateCachedData() {
+    int pageStart = getPageStart();
     int expectedLastIndex = Math.max(0,
-        Math.min(pageSize, rowCount - pageStart));
-    int lastIndex = rowData.size() - 1;
+        Math.min(getPageSize(), getRowCount() - pageStart));
+    int lastIndex = getRowDataSize() - 1;
     while (lastIndex >= expectedLastIndex) {
-      rowData.remove(lastIndex);
-      selectedRows.remove(lastIndex + pageStart);
+      ensurePendingState().rowData.remove(lastIndex);
       lastIndex--;
-      updated = true;
     }
-    return updated;
   }
 
   /**
    * Update the loading state of the view based on the data size and page size.
    */
   private void updateLoadingState() {
-    int cacheSize = rowData.size();
-    int curPageSize = isRowCountExact() ? getCurrentPageSize() : pageSize;
-    if (rowCount == 0 && rowCountIsExact) {
+    int cacheSize = getRowDataSize();
+    int curPageSize = isRowCountExact() ? getCurrentPageSize() : getPageSize();
+    if (getRowCount() == 0 && isRowCountExact()) {
       view.setLoadingState(LoadingState.EMPTY);
     } else if (cacheSize >= curPageSize) {
       view.setLoadingState(LoadingState.LOADED);
@@ -960,47 +1461,4 @@
       view.setLoadingState(LoadingState.PARTIALLY_LOADED);
     }
   }
-
-  /**
-   * Update the table based on the current selection.
-   */
-  private void updateSelection() {
-    view.onUpdateSelection();
-
-    // Determine if our selection states are stale.
-    boolean dependsOnSelection = view.dependsOnSelection();
-    boolean refreshRequired = false;
-    ElementIterator children = view.getChildIterator();
-    int row = pageStart;
-    for (T value : rowData) {
-      // Increment the child.
-      if (!children.hasNext()) {
-        break;
-      }
-      children.next();
-
-      // Update the selection state.
-      boolean selected = selectionModel == null ? false
-          : selectionModel.isSelected(value);
-      if (selected != selectedRows.contains(row)) {
-        refreshRequired = true;
-        if (selected) {
-          selectedRows.add(row);
-        } else {
-          selectedRows.remove(row);
-        }
-        if (!dependsOnSelection) {
-          // The cell doesn't depend on selection, so we only need to update
-          // the style.
-          children.setSelected(selected);
-        }
-      }
-      row++;
-    }
-
-    // Redraw the entire list if needed.
-    if (refreshRequired && dependsOnSelection) {
-      redraw();
-    }
-  }
 }
diff --git a/user/test/com/google/gwt/user/cellview/client/AbstractCellTreeTestBase.java b/user/test/com/google/gwt/user/cellview/client/AbstractCellTreeTestBase.java
index 17b1b35..8dbc539 100644
--- a/user/test/com/google/gwt/user/cellview/client/AbstractCellTreeTestBase.java
+++ b/user/test/com/google/gwt/user/cellview/client/AbstractCellTreeTestBase.java
@@ -17,6 +17,7 @@
 
 import com.google.gwt.cell.client.Cell;
 import com.google.gwt.cell.client.TextCell;
+import com.google.gwt.core.client.Scheduler;
 import com.google.gwt.event.logical.shared.CloseEvent;
 import com.google.gwt.event.logical.shared.CloseHandler;
 import com.google.gwt.event.logical.shared.OpenEvent;
@@ -24,7 +25,6 @@
 import com.google.gwt.junit.client.GWTTestCase;
 import com.google.gwt.safehtml.shared.SafeHtmlBuilder;
 import com.google.gwt.user.client.ui.RootPanel;
-import com.google.gwt.view.client.AbstractDataProvider;
 import com.google.gwt.view.client.ListDataProvider;
 import com.google.gwt.view.client.ProvidesKey;
 import com.google.gwt.view.client.TreeViewModel;
@@ -87,7 +87,7 @@
       throw new IllegalArgumentException("Unrecognized value type");
     }
 
-    public AbstractDataProvider<String> getRootDataProvider() {
+    public ListDataProvider<String> getRootDataProvider() {
       return rootDataProvider;
     }
 
@@ -235,9 +235,15 @@
     };
 
     // Create a tree.
-    new CellTree(model, null);
-    assertEquals("Cell#render() should be called exactly thrice", 3,
-        rendered.size());
+    createAbstractCellTree(model, null);
+    delayTestFinish(5000);
+    Scheduler.get().scheduleDeferred(new Scheduler.ScheduledCommand() {
+      public void execute() {
+        assertEquals("Cell#render() should be called exactly thrice", 3,
+            rendered.size());
+        finishTest();
+      }
+    });
   }
   
   /**
diff --git a/user/test/com/google/gwt/user/cellview/client/AbstractHasDataTestBase.java b/user/test/com/google/gwt/user/cellview/client/AbstractHasDataTestBase.java
index be504c6..b4ba250 100644
--- a/user/test/com/google/gwt/user/cellview/client/AbstractHasDataTestBase.java
+++ b/user/test/com/google/gwt/user/cellview/client/AbstractHasDataTestBase.java
@@ -127,6 +127,7 @@
     ListDataProvider<String> provider = new ListDataProvider<String>(
         createData(0, 10));
     provider.addDataDisplay(display);
+    display.getPresenter().flush();
 
     // Default tab index is 0.
     assertEquals(0, display.getTabIndex());
@@ -139,6 +140,7 @@
 
     // Push new data.
     provider.refresh();
+    display.getPresenter().flush();
     assertEquals(2, display.getTabIndex());
     assertEquals(2, display.getKeyboardSelectedElement().getTabIndex());
   }
diff --git a/user/test/com/google/gwt/user/cellview/client/CellBrowserTest.java b/user/test/com/google/gwt/user/cellview/client/CellBrowserTest.java
index 82bc7fe..11364e3 100644
--- a/user/test/com/google/gwt/user/cellview/client/CellBrowserTest.java
+++ b/user/test/com/google/gwt/user/cellview/client/CellBrowserTest.java
@@ -17,6 +17,8 @@
 
 import com.google.gwt.cell.client.NumberCell;
 import com.google.gwt.cell.client.TextCell;
+import com.google.gwt.user.cellview.client.CellBrowser.BrowserCellList;
+import com.google.gwt.user.cellview.client.HasKeyboardSelectionPolicy.KeyboardSelectionPolicy;
 import com.google.gwt.view.client.ListDataProvider;
 import com.google.gwt.view.client.TreeViewModel;
 
@@ -72,7 +74,7 @@
     assertEquals(1, browser.treeNodes.size());
 
     // Open a leaf node.
-    rootNode.setChildOpen(1, true);
+    assertNull(rootNode.setChildOpen(1, true));
     assertEquals(1, browser.treeNodes.size());
     assertEquals(1, browser.treeNodes.get(0).getFocusedKey());
     assertFalse(browser.treeNodes.get(0).isFocusedOpen());
@@ -80,7 +82,6 @@
     // Close the leaf node.
     rootNode.setChildOpen(1, false);
     assertEquals(1, browser.treeNodes.size());
-    assertNull(browser.treeNodes.get(0).getFocusedKey());
     assertFalse(browser.treeNodes.get(0).isFocusedOpen());
   }
 
@@ -117,6 +118,21 @@
     assertTrue(browser.treeNodes.get(0).isFocusedOpen());
   }
 
+  public void testSetKeyboardSelectionPolicyDisabled() {
+    CellBrowser browser = (CellBrowser) tree;
+
+    // Disable keyboard selection.
+    browser.setKeyboardSelectionPolicy(KeyboardSelectionPolicy.DISABLED);
+    assertEquals(KeyboardSelectionPolicy.DISABLED,
+        browser.getKeyboardSelectionPolicy());
+
+    // Verify that keyboard selection is enabled in the lists.
+    BrowserCellList<?> list = browser.treeNodes.get(0).getDisplay();
+    assertEquals(KeyboardSelectionPolicy.ENABLED,
+        list.getKeyboardSelectionPolicy());
+    assertTrue(list.isKeyboardNavigationSuppressed());
+  }
+
   @Override
   protected <T> CellBrowser createAbstractCellTree(TreeViewModel model,
       T rootValue) {
diff --git a/user/test/com/google/gwt/user/cellview/client/CellListTest.java b/user/test/com/google/gwt/user/cellview/client/CellListTest.java
index be56b60..261d237 100644
--- a/user/test/com/google/gwt/user/cellview/client/CellListTest.java
+++ b/user/test/com/google/gwt/user/cellview/client/CellListTest.java
@@ -22,6 +22,14 @@
  */
 public class CellListTest extends AbstractHasDataTestBase {
 
+  public void testGetRowElement() {
+    CellList<String> list = createAbstractHasData();
+    list.setRowData(0, createData(0, 10));
+
+    // Ensure that calling getRowElement() flushes all pending changes.
+    assertNotNull(list.getRowElement(9));
+  }
+
   @Override
   protected CellList<String> createAbstractHasData() {
     return new CellList<String>(new TextCell());
diff --git a/user/test/com/google/gwt/user/cellview/client/CellTableTest.java b/user/test/com/google/gwt/user/cellview/client/CellTableTest.java
index 4c42144..99a346d 100644
--- a/user/test/com/google/gwt/user/cellview/client/CellTableTest.java
+++ b/user/test/com/google/gwt/user/cellview/client/CellTableTest.java
@@ -21,15 +21,55 @@
 import com.google.gwt.dom.client.TableElement;
 import com.google.gwt.dom.client.TableRowElement;
 import com.google.gwt.dom.client.TableSectionElement;
+import com.google.gwt.safehtml.shared.SafeHtml;
 import com.google.gwt.user.cellview.client.CellTable.Resources;
 import com.google.gwt.user.cellview.client.CellTable.Style;
 
+import java.util.ArrayList;
+import java.util.List;
+
 /**
  * Tests for {@link CellTable}.
  */
 public class CellTableTest extends AbstractHasDataTestBase {
 
   /**
+   * Test that calls to addColumn results in only one redraw.
+   */
+  public void testAddColumnSingleRedraw() {
+    final List<SafeHtml> replaceValues = new ArrayList<SafeHtml>();
+    CellTable<String> table = new CellTable<String>() {
+      @Override
+      protected void replaceAllChildren(List<String> values, SafeHtml html) {
+        replaceValues.add(html);
+      }
+    };
+    table.addColumn(new Column<String, String>(new TextCell()) {
+      @Override
+      public String getValue(String object) {
+        return object + "-3";
+      }
+    });
+    table.addColumn(new Column<String, String>(new TextCell()) {
+      @Override
+      public String getValue(String object) {
+        return object + "-4";
+      }
+    });
+    table.setRowData(0, createData(0, 10));
+    table.getPresenter().flush();
+    assertEquals(1, replaceValues.size());
+  }
+  
+  public void testGetRowElement() {
+    CellTable<String> table = createAbstractHasData();
+    table.setRowData(0, createData(0, 10));
+
+    // Ensure that calling getRowElement() flushes all pending changes.
+    assertNotNull(table.getRowElement(9));
+  }
+
+  /**
    * Test headers that span multiple columns.
    */
   public void testMultiColumnHeader() {
@@ -45,6 +85,7 @@
 
     // No header.
     table.redraw();
+    table.getPresenter().flush();
     assertEquals(0, getHeaderCount(table));
 
     // Single column.
@@ -54,7 +95,7 @@
         return null;
       }
     }, header);
-    table.redraw();
+    table.getPresenter().flush();
     assertEquals(1, getHeaderCount(table));
     assertEquals(1, getHeaderElement(table, 0).getColSpan());
     assertTrue(getHeaderElement(table, 0).getClassName().contains(styleHeader));
@@ -70,7 +111,7 @@
         return null;
       }
     }, header);
-    table.redraw();
+    table.getPresenter().flush();
     assertEquals(1, getHeaderCount(table));
     assertEquals(2, getHeaderElement(table, 0).getColSpan());
     assertTrue(getHeaderElement(table, 0).getClassName().contains(styleHeader));
@@ -86,7 +127,7 @@
         return null;
       }
     }, header);
-    table.redraw();
+    table.getPresenter().flush();
     assertEquals(1, getHeaderCount(table));
     assertEquals(3, getHeaderElement(table, 0).getColSpan());
     assertTrue(getHeaderElement(table, 0).getClassName().contains(styleHeader));
@@ -102,7 +143,7 @@
         return null;
       }
     }, "New Header");
-    table.redraw();
+    table.getPresenter().flush();
     assertEquals(2, getHeaderCount(table));
     assertEquals(3, getHeaderElement(table, 0).getColSpan());
     assertTrue(getHeaderElement(table, 0).getClassName().contains(styleHeader));
@@ -126,7 +167,7 @@
         return null;
       }
     }, header);
-    table.redraw();
+    table.getPresenter().flush();
     assertEquals(3, getHeaderCount(table));
     assertEquals(3, getHeaderElement(table, 0).getColSpan());
     assertTrue(getHeaderElement(table, 0).getClassName().contains(styleHeader));
diff --git a/user/test/com/google/gwt/user/cellview/client/CellTreeTest.java b/user/test/com/google/gwt/user/cellview/client/CellTreeTest.java
index 07f5886..e5b43fb 100644
--- a/user/test/com/google/gwt/user/cellview/client/CellTreeTest.java
+++ b/user/test/com/google/gwt/user/cellview/client/CellTreeTest.java
@@ -26,6 +26,41 @@
     super(false);
   }
 
+  /**
+   * Test that replacing a subset of children updates both the TreeNode value
+   * and the underlying DOM correctly.
+   */
+  public void testReplaceChildren() {
+    CellTree cellTree = (CellTree) tree;
+    TreeNode root = cellTree.getRootTreeNode();
+
+    // Open a couple of child nodes.
+    TreeNode a = root.setChildOpen(0, true);
+    TreeNode b = root.setChildOpen(1, true);
+    assertEquals("a", a.getValue());
+    assertEquals("ab", a.getChildValue(1));
+    assertEquals("b", b.getValue());
+    assertEquals("bc", b.getChildValue(2));
+
+    // Replace "b" with a "new" value.
+    model.getRootDataProvider().getList().set(1, "new");
+    model.getRootDataProvider().flush();
+    assertFalse(a.isDestroyed());
+    assertTrue(b.isDestroyed());
+    TreeNode newNode = root.setChildOpen(1, true);
+    assertEquals("a", a.getValue());
+    assertEquals("ab", a.getChildValue(1));
+    assertEquals("new", newNode.getValue());
+    assertEquals("newc", newNode.getChildValue(2));
+    
+    // Check the underlying DOM values.
+    CellTreeNodeView<?> aImpl = cellTree.rootNode.getChildNode(0);
+    CellTreeNodeView<?> newNodeImpl = cellTree.rootNode.getChildNode(1);
+    assertEquals("a", aImpl.getCellParent().getInnerText());
+    assertEquals(10, aImpl.ensureChildContainer().getChildCount());
+    assertEquals("new", newNodeImpl.getCellParent().getInnerText());
+  }
+
   public void testSetDefaultNodeSize() {
     CellTree cellTree = (CellTree) tree;
     TreeNode root = cellTree.getRootTreeNode();
diff --git a/user/test/com/google/gwt/user/cellview/client/HasDataPresenterTest.java b/user/test/com/google/gwt/user/cellview/client/HasDataPresenterTest.java
index 2b825f1..5f48c3d 100644
--- a/user/test/com/google/gwt/user/cellview/client/HasDataPresenterTest.java
+++ b/user/test/com/google/gwt/user/cellview/client/HasDataPresenterTest.java
@@ -1,12 +1,12 @@
 /*
  * Copyright 2010 Google Inc.
- *
+ * 
  * Licensed under the Apache License, Version 2.0 (the "License"); you may not
  * use this file except in compliance with the License. You may obtain a copy of
  * the License at
- *
+ * 
  * http://www.apache.org/licenses/LICENSE-2.0
- *
+ * 
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
@@ -15,13 +15,13 @@
  */
 package com.google.gwt.user.cellview.client;
 
-import com.google.gwt.dom.client.Element;
+import com.google.gwt.core.client.Scheduler;
 import com.google.gwt.event.shared.EventHandler;
 import com.google.gwt.event.shared.GwtEvent.Type;
 import com.google.gwt.event.shared.HandlerRegistration;
+import com.google.gwt.junit.client.GWTTestCase;
 import com.google.gwt.safehtml.shared.SafeHtml;
 import com.google.gwt.safehtml.shared.SafeHtmlBuilder;
-import com.google.gwt.user.cellview.client.HasDataPresenter.ElementIterator;
 import com.google.gwt.user.cellview.client.HasDataPresenter.LoadingState;
 import com.google.gwt.user.cellview.client.HasDataPresenter.View;
 import com.google.gwt.user.cellview.client.HasKeyboardPagingPolicy.KeyboardPagingPolicy;
@@ -33,82 +33,33 @@
 import com.google.gwt.view.client.MockSelectionModel;
 import com.google.gwt.view.client.Range;
 import com.google.gwt.view.client.RangeChangeEvent;
+import com.google.gwt.view.client.SelectionChangeEvent;
 import com.google.gwt.view.client.SelectionModel;
-
-import junit.framework.TestCase;
+import com.google.gwt.view.client.SingleSelectionModel;
 
 import java.util.ArrayList;
-import java.util.HashSet;
 import java.util.List;
-import java.util.NoSuchElementException;
-import java.util.Set;
+import java.util.TreeSet;
 
 /**
  * Tests for {@link HasDataPresenter}.
  */
-public class HasDataPresenterTest extends TestCase {
-
-  /**
-   * Mock iterator over DOM elements.
-   */
-  private static class MockElementIterator implements ElementIterator {
-
-    private final int count;
-    private int next = 0;
-    private final MockView<?> view;
-
-    public MockElementIterator(MockView<?> view, int count) {
-      this.view = view;
-      this.count = count;
-    }
-
-    public boolean hasNext() {
-      return next < count;
-    }
-
-    public Element next() {
-      if (!hasNext()) {
-        throw new NoSuchElementException();
-      }
-      next++;
-      return null;
-    }
-
-    public void remove() {
-      throw new UnsupportedOperationException();
-    }
-
-    /**
-     * Set the selection state of the current element.
-     *
-     * @param selected the selection state
-     * @throws IllegalStateException if {@link #next()} has not been called
-     */
-    public void setSelected(boolean selected) throws IllegalStateException {
-      if (next == 0) {
-        throw new IllegalStateException();
-      }
-      view.setSelected(next - 1, selected);
-    }
-  }
+public class HasDataPresenterTest extends GWTTestCase {
 
   /**
    * A mock view used for testing.
-   *
+   * 
    * @param <T> the data type
    */
   private static class MockView<T> implements View<T> {
 
     private int childCount;
-    private boolean dependsOnSelection;
     private List<Integer> keyboardSelectedRow = new ArrayList<Integer>();
     private List<Boolean> keyboardSelectedRowState = new ArrayList<Boolean>();
-    private SafeHtml lastHtml;
+    private final List<SafeHtml> lastHtml = new ArrayList<SafeHtml>();
     private LoadingState loadingState;
-    private boolean onUpdateSelectionFired;
     private boolean replaceAllChildrenCalled;
     private boolean replaceChildrenCalled;
-    private Set<Integer> selectedRows = new HashSet<Integer>();
 
     public <H extends EventHandler> HandlerRegistration addHandler(H handler,
         Type<H> type) {
@@ -117,7 +68,7 @@
 
     /**
      * Assert the value of the oldest keyboard selected row and pop it.
-     *
+     * 
      * @param row the row index
      * @param selected true if selected, false if not
      */
@@ -137,22 +88,16 @@
 
     public void assertLastHtml(String html) {
       if (html == null) {
-        assertNull(lastHtml);
+        assertTrue(lastHtml.isEmpty());
       } else {
-        assertEquals(html, lastHtml.asString());
+        assertEquals(html, lastHtml.remove(0).asString());
       }
-      lastHtml = null;
     }
 
     public void assertLoadingState(LoadingState expected) {
       assertEquals(expected, loadingState);
     }
 
-    public void assertOnUpdateSelectionFired(boolean expected) {
-      assertEquals(expected, onUpdateSelectionFired);
-      onUpdateSelectionFired = false;
-    }
-
     public void assertReplaceAllChildrenCalled(boolean expected) {
       assertEquals(expected, replaceAllChildrenCalled);
       replaceAllChildrenCalled = false;
@@ -163,60 +108,33 @@
       replaceChildrenCalled = false;
     }
 
-    /**
-     * Assert that {@link #setSelected(int, boolean)} was called for the
-     * specified rows.
-     *
-     * @param rows the rows
-     */
-    public void assertSelectedRows(Integer... rows) {
-      assertEquals(rows.length, selectedRows.size());
-      for (Integer row : rows) {
-        assertTrue("Row " + row + "is not selected", selectedRows.contains(row));
-      }
-    }
-
-    public boolean dependsOnSelection() {
-      return dependsOnSelection;
-    }
-
     public int getChildCount() {
       return childCount;
     }
 
-    public MockElementIterator getChildIterator() {
-      return new MockElementIterator(this, 10);
-    }
-
-    public void onUpdateSelection() {
-      onUpdateSelectionFired = true;
-    }
-
     public void render(SafeHtmlBuilder sb, List<T> values, int start,
         SelectionModel<? super T> selectionModel) {
       sb.appendHtmlConstant("start=").append(start);
       sb.appendHtmlConstant(",size=").append(values.size());
     }
 
-    public void replaceAllChildren(List<T> values, SafeHtml html) {
+    public void replaceAllChildren(List<T> values, SafeHtml html,
+        boolean stealFocus) {
       childCount = values.size();
       replaceAllChildrenCalled = true;
-      lastHtml = html;
+      lastHtml.add(html);
     }
 
-    public void replaceChildren(List<T> values, int start, SafeHtml html) {
+    public void replaceChildren(List<T> values, int start, SafeHtml html,
+        boolean stealFocus) {
       childCount = Math.max(childCount, start + values.size());
       replaceChildrenCalled = true;
-      lastHtml = html;
+      lastHtml.add(html);
     }
 
     public void resetFocus() {
     }
 
-    public void setDependsOnSelection(boolean dependsOnSelection) {
-      this.dependsOnSelection = dependsOnSelection;
-    }
-
     public void setKeyboardSelected(int index, boolean selected,
         boolean stealFocus) {
       keyboardSelectedRow.add(index);
@@ -226,19 +144,11 @@
     public void setLoadingState(LoadingState state) {
       this.loadingState = state;
     }
+  }
 
-    public void setSelected(Element elem, boolean selected) {
-      // Not used in this mock.
-      throw new UnsupportedOperationException();
-    }
-
-    protected void setSelected(int index, boolean selected) {
-      if (selected) {
-        selectedRows.add(index);
-      } else {
-        selectedRows.remove(index);
-      }
-    }
+  @Override
+  public String getModuleName() {
+    return "com.google.gwt.user.cellview.CellView";
   }
 
   public void testAddRowCountChangeHandler() {
@@ -318,16 +228,55 @@
     handler.reset();
   }
 
+  public void testCalculateModifiedRanges() {
+    HasData<String> listView = new MockHasData<String>();
+    MockView<String> view = new MockView<String>();
+    HasDataPresenter<String> presenter = new HasDataPresenter<String>(listView,
+        view, 10, null);
+
+    TreeSet<Integer> rows = new TreeSet<Integer>();
+
+    // Empty set of rows.
+    assertListContains(presenter.calculateModifiedRanges(rows, 0, 10));
+
+    // One row in range.
+    rows.add(5);
+    assertListContains(presenter.calculateModifiedRanges(rows, 0, 10),
+        new Range(5, 1));
+
+    // One row not in range.
+    assertListContains(presenter.calculateModifiedRanges(rows, 6, 10));
+
+    // Consecutive rows (should return only one range).
+    rows.add(6);
+    rows.add(7);
+    rows.add(8);
+    assertListContains(presenter.calculateModifiedRanges(rows, 0, 10),
+        new Range(5, 4));
+
+    // Disjoint rows. Should return two ranges.
+    rows.add(10);
+    rows.add(11);
+    assertListContains(presenter.calculateModifiedRanges(rows, 0, 20),
+        new Range(5, 4), new Range(10, 2));
+
+    // Multiple gaps. The largest gap should be between the two ranges.
+    rows.add(15);
+    rows.add(17);
+    assertListContains(presenter.calculateModifiedRanges(rows, 0, 20),
+        new Range(5, 7), new Range(15, 3));
+  }
+
   public void testClearSelectionModel() {
     HasData<String> listView = new MockHasData<String>();
     MockView<String> view = new MockView<String>();
-    view.setDependsOnSelection(true);
     HasDataPresenter<String> presenter = new HasDataPresenter<String>(listView,
         view, 10, null);
     assertNull(presenter.getSelectionModel());
 
     // Initialize some data.
     populatePresenter(presenter);
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=0,size=10");
@@ -336,19 +285,17 @@
     SelectionModel<String> model = new MockSelectionModel<String>(null);
     model.setSelected("test 0", true);
     presenter.setSelectionModel(model);
-    view.assertReplaceAllChildrenCalled(true);
-    view.assertReplaceChildrenCalled(false);
-    view.assertLastHtml("start=0,size=10");
-    view.assertOnUpdateSelectionFired(true);
-    view.assertSelectedRows();
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(false);
+    view.assertReplaceChildrenCalled(true);
+    view.assertLastHtml("start=0,size=1");
 
     // Clear the selection model without updating the view.
     presenter.clearSelectionModel();
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(false);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml(null);
-    view.assertOnUpdateSelectionFired(false);
-    view.assertSelectedRows();
   }
 
   public void testDefaults() {
@@ -363,6 +310,50 @@
     assertEquals(new Range(0, 10), presenter.getVisibleRange());
   }
 
+  /**
+   * Test that keyboard selection moves if its value moves.
+   */
+  public void testFindIndexOfBestMatch() {
+    HasData<String> listView = new MockHasData<String>();
+    MockView<String> view = new MockView<String>();
+    HasDataPresenter<String> presenter = new HasDataPresenter<String>(listView,
+        view, 10, null);
+    populatePresenter(presenter);
+
+    // Select the second element.
+    presenter.setKeyboardSelectedRow(2, false);
+    presenter.flush();
+    assertEquals(2, presenter.getKeyboardSelectedRow());
+    assertEquals("test 2", presenter.getKeyboardSelectedRowValue());
+
+    // Shift the values by one.
+    presenter.setRowData(1, createData(0, 9));
+    presenter.flush();
+    assertEquals(3, presenter.getKeyboardSelectedRow());
+    assertEquals("test 2", presenter.getKeyboardSelectedRowValue());
+
+    // Replace the keyboard selected value.
+    presenter.setRowData(0, createData(100, 10));
+    presenter.flush();
+    assertEquals(0, presenter.getKeyboardSelectedRow());
+    assertEquals(null, presenter.getKeyboardSelectedRowValue());
+  }
+
+  public void testFlush() {
+    HasData<String> listView = new MockHasData<String>();
+    MockView<String> view = new MockView<String>();
+    HasDataPresenter<String> presenter = new HasDataPresenter<String>(listView,
+        view, 10, null);
+
+    // Data should not be pushed to the view until flushed.
+    populatePresenter(presenter);
+    view.assertReplaceAllChildrenCalled(false);
+
+    // Now the data is pushed.
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(true);
+  }
+
   public void testGetCurrentPageSize() {
     HasData<String> listView = new MockHasData<String>();
     MockView<String> view = new MockView<String>();
@@ -386,32 +377,39 @@
     presenter.setRowCount(100, true);
     presenter.setVisibleRange(new Range(50, 10));
     populatePresenter(presenter);
+    presenter.flush();
     presenter.setKeyboardPagingPolicy(KeyboardPagingPolicy.CHANGE_PAGE);
 
     // keyboardPrev in middle.
     presenter.setKeyboardSelectedRow(1, false);
+    presenter.flush();
     view.assertKeyboardSelectedRow(0, false);
     view.assertKeyboardSelectedRow(1, true);
     assertTrue(presenter.hasKeyboardPrev());
     presenter.keyboardPrev();
+    presenter.flush();
     assertEquals(0, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRow(1, false);
     view.assertKeyboardSelectedRow(0, true);
 
-    // keyboardPrev at beginning.
+    // keyboardPrev at beginning goes to previous page.
     assertTrue(presenter.hasKeyboardPrev());
     presenter.keyboardPrev();
-    assertEquals(9, presenter.getKeyboardSelectedRow());
-    view.assertKeyboardSelectedRow(0, false);
-    assertEquals(new Range(40, 10), presenter.getVisibleRange());
     populatePresenter(presenter);
+    presenter.flush();
+    assertEquals(9, presenter.getKeyboardSelectedRow());
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertKeyboardSelectedRowEmpty();
+    assertEquals(new Range(40, 10), presenter.getVisibleRange());
 
     // keyboardNext in middle.
     presenter.setKeyboardSelectedRow(8, false);
+    presenter.flush();
     view.assertKeyboardSelectedRow(9, false);
     view.assertKeyboardSelectedRow(8, true);
     assertTrue(presenter.hasKeyboardNext());
     presenter.keyboardNext();
+    presenter.flush();
     assertEquals(9, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRow(8, false);
     view.assertKeyboardSelectedRow(9, true);
@@ -419,53 +417,69 @@
     // keyboardNext at end.
     assertTrue(presenter.hasKeyboardNext());
     presenter.keyboardNext();
-    assertEquals(0, presenter.getKeyboardSelectedRow());
-    view.assertKeyboardSelectedRow(9, false);
-    assertEquals(new Range(50, 10), presenter.getVisibleRange());
     populatePresenter(presenter);
+    presenter.flush();
+    assertEquals(0, presenter.getKeyboardSelectedRow());
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertKeyboardSelectedRowEmpty();
+    assertEquals(new Range(50, 10), presenter.getVisibleRange());
 
     // keyboardPrevPage.
     presenter.setKeyboardSelectedRow(5, false);
+    presenter.flush();
     view.assertKeyboardSelectedRow(0, false);
     view.assertKeyboardSelectedRow(5, true);
     presenter.keyboardPrevPage();
-    assertEquals(0, presenter.getKeyboardSelectedRow());
-    view.assertKeyboardSelectedRow(5, false);
-    assertEquals(new Range(40, 10), presenter.getVisibleRange());
     populatePresenter(presenter);
+    presenter.flush();
+    assertEquals(0, presenter.getKeyboardSelectedRow());
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertKeyboardSelectedRowEmpty();
+    assertEquals(new Range(40, 10), presenter.getVisibleRange());
 
     // keyboardNextPage.
     presenter.setKeyboardSelectedRow(5, false);
+    presenter.flush();
     view.assertKeyboardSelectedRow(0, false);
     view.assertKeyboardSelectedRow(5, true);
     presenter.keyboardNextPage();
-    assertEquals(0, presenter.getKeyboardSelectedRow());
-    view.assertKeyboardSelectedRow(5, false);
-    assertEquals(new Range(50, 10), presenter.getVisibleRange());
     populatePresenter(presenter);
+    presenter.flush();
+    assertEquals(0, presenter.getKeyboardSelectedRow());
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertKeyboardSelectedRowEmpty();
+    assertEquals(new Range(50, 10), presenter.getVisibleRange());
 
     // keyboardHome.
     presenter.keyboardHome();
-    assertEquals(0, presenter.getKeyboardSelectedRow());
-    view.assertKeyboardSelectedRow(0, false);
-    assertEquals(new Range(0, 10), presenter.getVisibleRange());
     populatePresenter(presenter);
+    presenter.flush();
+    assertEquals(0, presenter.getKeyboardSelectedRow());
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertKeyboardSelectedRowEmpty();
+    assertEquals(new Range(0, 10), presenter.getVisibleRange());
 
     // keyboardPrev at first row.
     assertFalse(presenter.hasKeyboardPrev());
     presenter.keyboardPrev();
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(false);
     view.assertKeyboardSelectedRowEmpty();
 
     // keyboardEnd.
     presenter.keyboardEnd();
-    assertEquals(9, presenter.getKeyboardSelectedRow());
-    view.assertKeyboardSelectedRow(0, false);
-    assertEquals(new Range(90, 10), presenter.getVisibleRange());
     populatePresenter(presenter);
+    presenter.flush();
+    assertEquals(9, presenter.getKeyboardSelectedRow());
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertKeyboardSelectedRowEmpty();
+    assertEquals(new Range(90, 10), presenter.getVisibleRange());
 
     // keyboardNext at last row.
     assertFalse(presenter.hasKeyboardNext());
     presenter.keyboardNext();
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(false);
     view.assertKeyboardSelectedRowEmpty();
   }
 
@@ -476,14 +490,17 @@
         view, 10, null);
     presenter.setVisibleRange(new Range(50, 10));
     populatePresenter(presenter);
+    presenter.flush();
     presenter.setKeyboardPagingPolicy(KeyboardPagingPolicy.CURRENT_PAGE);
 
     // keyboardPrev in middle.
     presenter.setKeyboardSelectedRow(1, false);
+    presenter.flush();
     view.assertKeyboardSelectedRow(0, false);
     view.assertKeyboardSelectedRow(1, true);
     assertTrue(presenter.hasKeyboardPrev());
     presenter.keyboardPrev();
+    presenter.flush();
     assertEquals(0, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRow(1, false);
     view.assertKeyboardSelectedRow(0, true);
@@ -491,15 +508,18 @@
     // keyboardPrev at beginning.
     assertFalse(presenter.hasKeyboardPrev());
     presenter.keyboardPrev();
+    presenter.flush();
     assertEquals(0, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRowEmpty();
 
     // keyboardNext in middle.
     presenter.setKeyboardSelectedRow(8, false);
+    presenter.flush();
     view.assertKeyboardSelectedRow(0, false);
     view.assertKeyboardSelectedRow(8, true);
     assertTrue(presenter.hasKeyboardNext());
     presenter.keyboardNext();
+    presenter.flush();
     assertEquals(9, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRow(8, false);
     view.assertKeyboardSelectedRow(9, true);
@@ -507,23 +527,28 @@
     // keyboardNext at end.
     assertFalse(presenter.hasKeyboardNext());
     presenter.keyboardNext();
+    presenter.flush();
     assertEquals(9, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRowEmpty();
 
     // keyboardPrevPage.
     presenter.keyboardPrevPage();
+    presenter.flush();
     view.assertKeyboardSelectedRowEmpty();
 
     // keyboardNextPage.
     presenter.keyboardNextPage();
+    presenter.flush();
     view.assertKeyboardSelectedRowEmpty();
 
     // keyboardHome.
     presenter.keyboardHome();
+    presenter.flush();
     view.assertKeyboardSelectedRowEmpty();
 
     // keyboardEnd.
     presenter.keyboardEnd();
+    presenter.flush();
     view.assertKeyboardSelectedRowEmpty();
   }
 
@@ -538,14 +563,17 @@
     presenter.setRowCount(300, true);
     presenter.setVisibleRange(new Range(pageStart, pageSize));
     populatePresenter(presenter);
+    presenter.flush();
     presenter.setKeyboardPagingPolicy(KeyboardPagingPolicy.INCREASE_RANGE);
 
     // keyboardPrev in middle.
     presenter.setKeyboardSelectedRow(1, false);
+    presenter.flush();
     view.assertKeyboardSelectedRow(0, false);
     view.assertKeyboardSelectedRow(1, true);
     assertTrue(presenter.hasKeyboardPrev());
     presenter.keyboardPrev();
+    presenter.flush();
     assertEquals(0, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRow(1, false);
     view.assertKeyboardSelectedRow(0, true);
@@ -553,19 +581,23 @@
     // keyboardPrev at beginning.
     assertTrue(presenter.hasKeyboardPrev());
     presenter.keyboardPrev();
-    view.assertKeyboardSelectedRow(0, false);
+    populatePresenter(presenter);
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertKeyboardSelectedRowEmpty();
     pageStart -= increment;
     pageSize += increment;
     assertEquals(increment - 1, presenter.getKeyboardSelectedRow());
     assertEquals(new Range(pageStart, pageSize), presenter.getVisibleRange());
-    populatePresenter(presenter);
 
     // keyboardNext in middle.
     presenter.setKeyboardSelectedRow(pageSize - 2, false);
+    presenter.flush();
     view.assertKeyboardSelectedRow(increment - 1, false);
     view.assertKeyboardSelectedRow(pageSize - 2, true);
     assertTrue(presenter.hasKeyboardNext());
     presenter.keyboardNext();
+    presenter.flush();
     assertEquals(pageSize - 1, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRow(pageSize - 2, false);
     view.assertKeyboardSelectedRow(pageSize - 1, true);
@@ -573,17 +605,21 @@
     // keyboardNext at end.
     assertTrue(presenter.hasKeyboardNext());
     presenter.keyboardNext();
-    view.assertKeyboardSelectedRow(pageSize - 1, false);
+    populatePresenter(presenter);
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertKeyboardSelectedRowEmpty();
     pageSize += increment;
     assertEquals(pageSize - increment, presenter.getKeyboardSelectedRow());
     assertEquals(new Range(pageStart, pageSize), presenter.getVisibleRange());
-    populatePresenter(presenter);
 
     // keyboardPrevPage within range.
     presenter.setKeyboardSelectedRow(increment, false);
+    presenter.flush();
     view.assertKeyboardSelectedRow(pageSize - increment, false);
     view.assertKeyboardSelectedRow(increment, true);
     presenter.keyboardPrevPage();
+    presenter.flush();
     assertEquals(0, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRow(increment, false);
     view.assertKeyboardSelectedRow(0, true);
@@ -591,59 +627,123 @@
 
     // keyboardPrevPage outside range.
     presenter.keyboardPrevPage();
+    populatePresenter(presenter);
+    presenter.flush();
     assertEquals(0, presenter.getKeyboardSelectedRow());
-    view.assertKeyboardSelectedRow(0, false);
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertKeyboardSelectedRowEmpty();
     pageStart -= increment;
     pageSize += increment;
     assertEquals(new Range(pageStart, pageSize), presenter.getVisibleRange());
-    populatePresenter(presenter);
 
     // keyboardNextPage inside range.
     presenter.keyboardNextPage();
+    presenter.flush();
     assertEquals(increment, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRow(0, false);
     view.assertKeyboardSelectedRow(increment, true);
     assertEquals(new Range(pageStart, pageSize), presenter.getVisibleRange());
-    populatePresenter(presenter);
 
     // keyboardNextPage outside range.
     presenter.setKeyboardSelectedRow(pageSize - 1, false);
+    presenter.flush();
     view.assertKeyboardSelectedRow(increment, false);
     view.assertKeyboardSelectedRow(pageSize - 1, true);
     presenter.keyboardNextPage();
-    view.assertKeyboardSelectedRow(pageSize - 1, false);
+    populatePresenter(presenter);
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertKeyboardSelectedRowEmpty();
     pageSize += increment;
     assertEquals(pageSize - 1, presenter.getKeyboardSelectedRow());
     assertEquals(new Range(pageStart, pageSize), presenter.getVisibleRange());
-    populatePresenter(presenter);
 
     // keyboardHome.
     presenter.keyboardHome();
-    view.assertKeyboardSelectedRow(pageSize - 1, false);
+    populatePresenter(presenter);
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertKeyboardSelectedRowEmpty();
     pageSize += pageStart;
     pageStart = 0;
     assertEquals(0, presenter.getKeyboardSelectedRow());
     assertEquals(new Range(pageStart, pageSize), presenter.getVisibleRange());
-    populatePresenter(presenter);
 
     // keyboardPrev at first row.
     assertFalse(presenter.hasKeyboardPrev());
     presenter.keyboardPrev();
+    presenter.flush();
     view.assertKeyboardSelectedRowEmpty();
 
     // keyboardEnd.
     presenter.keyboardEnd();
-    view.assertKeyboardSelectedRow(0, false);
+    populatePresenter(presenter);
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertKeyboardSelectedRowEmpty();
     assertEquals(299, presenter.getKeyboardSelectedRow());
     assertEquals(new Range(0, 300), presenter.getVisibleRange());
-    populatePresenter(presenter);
 
     // keyboardNext at last row.
     assertFalse(presenter.hasKeyboardNext());
     presenter.keyboardNext();
+    presenter.flush();
     view.assertKeyboardSelectedRowEmpty();
   }
 
+  /**
+   * Test that we can detect an infinite loop caused by user code updating the
+   * presenter every time we try to resolve state.
+   */
+  public void testLoopDetection() {
+    HasData<String> listView = new MockHasData<String>();
+    final MockView<String> view = new MockView<String>();
+    final HasDataPresenter<String> presenter = new HasDataPresenter<String>(
+        listView, view, 10, null);
+    presenter.setSelectionModel(new SingleSelectionModel<String>() {
+      @Override
+      public boolean isSelected(String object) {
+        // This selection model triggers a selection change event every time it
+        // is accessed, which puts the presenter in a pending state.
+        SelectionChangeEvent.fire(this);
+        return super.isSelected(object);
+      }
+    });
+
+    populatePresenter(presenter);
+    try {
+      presenter.flush();
+      fail("Expected IllegalStateException because of infinite loop.");
+    } catch (IllegalStateException e) {
+      // Expected.
+    }
+  }
+
+  /**
+   * Test that pending command execute in a finally loop.
+   */
+  public void testPendingCommand() {
+    HasData<String> listView = new MockHasData<String>();
+    final MockView<String> view = new MockView<String>();
+    final HasDataPresenter<String> presenter = new HasDataPresenter<String>(
+        listView, view, 10, null);
+
+    // Data should not be pushed to the view until the pending command executes.
+    populatePresenter(presenter);
+    assertTrue(presenter.hasPendingState());
+    view.assertReplaceAllChildrenCalled(false);
+
+    // The pending command is scheduled. Wait for it to execute.
+    delayTestFinish(5000);
+    Scheduler.get().scheduleDeferred(new Scheduler.ScheduledCommand() {
+      public void execute() {
+        assertFalse(presenter.hasPendingState());
+        view.assertReplaceAllChildrenCalled(true);
+        finishTest();
+      }
+    });
+  }
+
   public void testRedraw() {
     HasData<String> listView = new MockHasData<String>();
     MockView<String> view = new MockView<String>();
@@ -653,8 +753,9 @@
     // Initialize some data.
     presenter.setRowCount(10, true);
     populatePresenter(presenter);
-    assertEquals(10, presenter.getRowData().size());
-    assertEquals("test 0", presenter.getRowData().get(0));
+    presenter.flush();
+    assertEquals(10, presenter.getRowDataSize());
+    assertEquals("test 0", presenter.getRowDataValue(0));
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=0,size=10");
@@ -662,6 +763,8 @@
 
     // Redraw.
     presenter.redraw();
+    view.assertReplaceAllChildrenCalled(false);
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=0,size=10");
@@ -675,6 +778,7 @@
         view, 10, null);
     presenter.setVisibleRange(new Range(0, 10));
     populatePresenter(presenter);
+    presenter.flush();
 
     // The default is ENABLED.
     assertEquals(KeyboardSelectionPolicy.ENABLED,
@@ -687,26 +791,31 @@
     // Add a selection model.
     MockSelectionModel<String> model = new MockSelectionModel<String>(null);
     presenter.setSelectionModel(model);
+    presenter.flush();
     assertEquals(0, model.getSelectedSet().size());
 
     // Select an element.
     presenter.setKeyboardSelectedRow(5, false);
+    presenter.flush();
     assertEquals(1, model.getSelectedSet().size());
     assertTrue(model.isSelected("test 5"));
 
     // Select another element.
     presenter.setKeyboardSelectedRow(9, false);
+    presenter.flush();
     assertEquals(1, model.getSelectedSet().size());
     assertTrue(model.isSelected("test 9"));
 
     // Select an element on another page.
     presenter.setKeyboardSelectedRow(11, false);
+    presenter.flush();
     // Nothing is selected yet because we don't have data.
     assertEquals(0, model.getSelectedSet().size());
     populatePresenter(presenter);
+    presenter.flush();
     // Once data is pushed, the selection model should be populated.
     assertEquals(1, model.getSelectedSet().size());
-    assertTrue(model.isSelected("test 11"));
+    assertTrue(model.isSelected("test 10"));
   }
 
   public void testSetKeyboardSelectedRowChangePage() {
@@ -716,6 +825,7 @@
         view, 10, null);
     presenter.setVisibleRange(new Range(10, 10));
     populatePresenter(presenter);
+    presenter.flush();
 
     // Default policy is CHANGE_PAGE.
     assertEquals(KeyboardPagingPolicy.CHANGE_PAGE,
@@ -727,19 +837,28 @@
 
     // Move to middle.
     presenter.setKeyboardSelectedRow(1, false);
+    assertEquals("test 11", presenter.getKeyboardSelectedRowValue());
+    presenter.flush();
     assertEquals(1, presenter.getKeyboardSelectedRow());
+    assertEquals("test 11", presenter.getKeyboardSelectedRowValue());
     view.assertKeyboardSelectedRow(0, false);
     view.assertKeyboardSelectedRow(1, true);
 
     // Move to same row (should not early out).
     presenter.setKeyboardSelectedRow(1, false);
+    assertEquals("test 11", presenter.getKeyboardSelectedRowValue());
+    presenter.flush();
     assertEquals(1, presenter.getKeyboardSelectedRow());
+    assertEquals("test 11", presenter.getKeyboardSelectedRowValue());
     view.assertKeyboardSelectedRow(1, false);
     view.assertKeyboardSelectedRow(1, true);
 
     // Move to last row.
     presenter.setKeyboardSelectedRow(9, false);
+    assertEquals("test 19", presenter.getKeyboardSelectedRowValue());
+    presenter.flush();
     assertEquals(9, presenter.getKeyboardSelectedRow());
+    assertEquals("test 19", presenter.getKeyboardSelectedRowValue());
     view.assertKeyboardSelectedRow(1, false);
     view.assertKeyboardSelectedRow(9, true);
     assertEquals(10, presenter.getVisibleRange().getStart());
@@ -747,19 +866,25 @@
 
     // Move to next page.
     presenter.setKeyboardSelectedRow(10, false);
+    populatePresenter(presenter);
+    assertNull(presenter.getKeyboardSelectedRowValue());
+    presenter.flush();
     assertEquals(0, presenter.getKeyboardSelectedRow());
-    view.assertKeyboardSelectedRow(9, false);
-    // Select is not fired because there is no row data yet.
+    assertEquals("test 20", presenter.getKeyboardSelectedRowValue());
+    view.assertReplaceAllChildrenCalled(true);
     view.assertKeyboardSelectedRowEmpty();
     assertEquals(20, presenter.getVisibleRange().getStart());
     assertEquals(10, presenter.getVisibleRange().getLength());
-    populatePresenter(presenter);
 
     // Negative index.
     presenter.setKeyboardSelectedRow(-1, false);
+    populatePresenter(presenter);
+    assertNull(presenter.getKeyboardSelectedRowValue());
+    presenter.flush();
     assertEquals(9, presenter.getKeyboardSelectedRow());
-    view.assertKeyboardSelectedRow(0, false);
-    // Select is not fired because there is no row data yet.
+    assertEquals("test 19", presenter.getKeyboardSelectedRowValue());
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertKeyboardSelectedRowEmpty();
     assertEquals(10, presenter.getVisibleRange().getStart());
     assertEquals(10, presenter.getVisibleRange().getLength());
   }
@@ -771,6 +896,7 @@
         view, 10, null);
     presenter.setVisibleRange(new Range(10, 10));
     populatePresenter(presenter);
+    presenter.flush();
     presenter.setKeyboardPagingPolicy(KeyboardPagingPolicy.CURRENT_PAGE);
 
     // Default to row 0.
@@ -779,30 +905,35 @@
 
     // Negative index (should remain at index 0).
     presenter.setKeyboardSelectedRow(-1, false);
+    presenter.flush();
     assertEquals(0, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRow(0, false);
     view.assertKeyboardSelectedRow(0, true);
 
     // Move to middle.
     presenter.setKeyboardSelectedRow(1, false);
+    presenter.flush();
     assertEquals(1, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRow(0, false);
     view.assertKeyboardSelectedRow(1, true);
 
     // Move to same row (should not early out).
     presenter.setKeyboardSelectedRow(1, false);
+    presenter.flush();
     assertEquals(1, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRow(1, false);
     view.assertKeyboardSelectedRow(1, true);
 
     // Move to last row.
     presenter.setKeyboardSelectedRow(9, false);
+    presenter.flush();
     assertEquals(9, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRow(1, false);
     view.assertKeyboardSelectedRow(9, true);
 
     // Move to next page (confined to page).
     presenter.setKeyboardSelectedRow(10, false);
+    presenter.flush();
     assertEquals(9, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRow(9, false);
     view.assertKeyboardSelectedRow(9, true);
@@ -818,13 +949,17 @@
         view, 10, null);
     presenter.setVisibleRange(new Range(10, 10));
     populatePresenter(presenter);
+    presenter.flush();
     presenter.setKeyboardSelectionPolicy(KeyboardSelectionPolicy.DISABLED);
 
     assertEquals(-1, presenter.getKeyboardSelectedRow());
+    assertNull(presenter.getKeyboardSelectedRowValue());
     view.assertKeyboardSelectedRowEmpty();
 
     presenter.setKeyboardSelectedRow(1, false);
+    presenter.flush();
     assertEquals(-1, presenter.getKeyboardSelectedRow());
+    assertNull(presenter.getKeyboardSelectedRowValue());
     view.assertKeyboardSelectedRowEmpty();
   }
 
@@ -835,6 +970,7 @@
         view, 10, null);
     presenter.setVisibleRange(new Range(10, 10));
     populatePresenter(presenter);
+    presenter.flush();
     presenter.setKeyboardPagingPolicy(KeyboardPagingPolicy.INCREASE_RANGE);
     int pageSize = presenter.getVisibleRange().getLength();
 
@@ -844,18 +980,21 @@
 
     // Move to middle.
     presenter.setKeyboardSelectedRow(1, false);
+    presenter.flush();
     assertEquals(1, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRow(0, false);
     view.assertKeyboardSelectedRow(1, true);
 
     // Move to same row (should not early out).
     presenter.setKeyboardSelectedRow(1, false);
+    presenter.flush();
     assertEquals(1, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRow(1, false);
     view.assertKeyboardSelectedRow(1, true);
 
     // Move to last row.
     presenter.setKeyboardSelectedRow(9, false);
+    presenter.flush();
     assertEquals(9, presenter.getKeyboardSelectedRow());
     view.assertKeyboardSelectedRow(1, false);
     view.assertKeyboardSelectedRow(9, true);
@@ -864,20 +1003,22 @@
 
     // Move to next page.
     presenter.setKeyboardSelectedRow(10, false);
+    populatePresenter(presenter);
+    presenter.flush();
     assertEquals(10, presenter.getKeyboardSelectedRow());
-    view.assertKeyboardSelectedRow(9, false);
-    // Select is not fired because there is no row data yet.
+    view.assertReplaceAllChildrenCalled(true);
     view.assertKeyboardSelectedRowEmpty();
     assertEquals(10, presenter.getVisibleRange().getStart());
     pageSize += HasDataPresenter.PAGE_INCREMENT;
     assertEquals(pageSize, presenter.getVisibleRange().getLength());
-    populatePresenter(presenter);
 
     // Negative index near index 0.
     presenter.setKeyboardSelectedRow(-1, false);
+    populatePresenter(presenter);
+    presenter.flush();
     assertEquals(9, presenter.getKeyboardSelectedRow());
-    view.assertKeyboardSelectedRow(10, false);
-    // Select is not fired because there is no row data yet.
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertKeyboardSelectedRowEmpty();
     assertEquals(0, presenter.getVisibleRange().getStart());
     pageSize += 10;
     assertEquals(pageSize, presenter.getVisibleRange().getLength());
@@ -894,6 +1035,7 @@
     presenter.setRowCount(100, true);
     assertEquals(100, presenter.getRowCount());
     assertTrue(presenter.isRowCountExact());
+    presenter.flush();
     view.assertLoadingState(LoadingState.LOADING);
 
     // Set size to 0, but not exact. The state is loading until we know there is
@@ -901,12 +1043,14 @@
     presenter.setRowCount(0, false);
     assertEquals(0, presenter.getRowCount());
     assertFalse(presenter.isRowCountExact());
+    presenter.flush();
     view.assertLoadingState(LoadingState.LOADING);
 
     // Set size to 0 and exact. Now we know the list is empty.
     presenter.setRowCount(0, true);
     assertEquals(0, presenter.getRowCount());
     assertTrue(presenter.isRowCountExact());
+    presenter.flush();
     view.assertLoadingState(LoadingState.EMPTY);
   }
 
@@ -936,8 +1080,10 @@
     presenter.setVisibleRange(new Range(0, 10));
     assertEquals(new Range(0, 10), presenter.getVisibleRange());
     populatePresenter(presenter);
-    assertEquals(10, presenter.getRowData().size());
-    assertEquals("test 0", presenter.getRowData().get(0));
+    presenter.flush();
+    assertEquals(10, presenter.getRowDataSize());
+    assertEquals("test 0", presenter.getRowDataValue(0));
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=0,size=10");
@@ -948,7 +1094,8 @@
     assertEquals(8, presenter.getRowCount());
     assertTrue(presenter.isRowCountExact());
     assertEquals(new Range(0, 10), presenter.getVisibleRange());
-    assertEquals(8, presenter.getRowData().size());
+    assertEquals(8, presenter.getRowDataSize());
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=0,size=8");
@@ -961,13 +1108,15 @@
     HasDataPresenter<String> presenter = new HasDataPresenter<String>(listView,
         view, 10, null);
     presenter.setVisibleRange(new Range(5, 10));
+    presenter.flush();
+    view.assertLastHtml("start=5,size=0");
     view.assertLoadingState(LoadingState.LOADING);
 
     // Page range same as data range.
     List<String> expectedData = createData(5, 10);
     presenter.setRowData(5, createData(5, 10));
-    assertEquals(10, presenter.getRowData().size());
-    assertEquals(expectedData, presenter.getRowData());
+    assertPresenterRowData(expectedData, presenter);
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=5,size=10");
@@ -978,8 +1127,8 @@
     expectedData.set(2, "test 100");
     expectedData.set(3, "test 101");
     presenter.setRowData(7, createData(100, 2));
-    assertEquals(10, presenter.getRowData().size());
-    assertEquals(expectedData, presenter.getRowData());
+    assertPresenterRowData(expectedData, presenter);
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(false);
     view.assertReplaceChildrenCalled(true);
     view.assertLastHtml("start=7,size=2");
@@ -990,8 +1139,8 @@
     expectedData.set(0, "test 202");
     expectedData.set(1, "test 203");
     presenter.setRowData(3, createData(200, 4));
-    assertEquals(10, presenter.getRowData().size());
-    assertEquals(expectedData, presenter.getRowData());
+    assertPresenterRowData(expectedData, presenter);
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(false);
     view.assertReplaceChildrenCalled(true);
     view.assertLastHtml("start=5,size=2");
@@ -1002,8 +1151,8 @@
     expectedData.set(8, "test 300");
     expectedData.set(9, "test 301");
     presenter.setRowData(13, createData(300, 4));
-    assertEquals(10, presenter.getRowData().size());
-    assertEquals(expectedData, presenter.getRowData());
+    assertPresenterRowData(expectedData, presenter);
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(false);
     view.assertReplaceChildrenCalled(true);
     view.assertLastHtml("start=13,size=2");
@@ -1013,8 +1162,8 @@
     // Data range contains page range.
     expectedData = createData(400, 20).subList(2, 12);
     presenter.setRowData(3, createData(400, 20));
-    assertEquals(10, presenter.getRowData().size());
-    assertEquals(expectedData, presenter.getRowData());
+    assertPresenterRowData(expectedData, presenter);
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=5,size=10");
@@ -1033,15 +1182,18 @@
 
     // Set the initial data size.
     presenter.setRowCount(10, true);
+    presenter.flush();
     view.assertLoadingState(LoadingState.LOADING);
 
     // Set the data within the range.
     presenter.setRowData(0, createData(0, 10));
+    presenter.flush();
     view.assertLoadingState(LoadingState.LOADED);
 
     // Set the data past the range.
     presenter.setRowData(5, createData(5, 10));
     assertEquals(15, presenter.getRowCount());
+    presenter.flush();
     view.assertLoadingState(LoadingState.LOADED);
   }
 
@@ -1057,10 +1209,12 @@
 
     // Set the initial data size.
     presenter.setRowCount(10, true);
+    presenter.flush();
     view.assertLoadingState(LoadingState.LOADING);
 
     // Set an empty list of row values.
     presenter.setRowData(0, createData(0, 0));
+    presenter.flush();
     view.assertLoadingState(LoadingState.LOADING);
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
@@ -1072,13 +1226,15 @@
     HasDataPresenter<String> presenter = new HasDataPresenter<String>(listView,
         view, 10, null);
     presenter.setVisibleRange(new Range(5, 10));
+    presenter.flush();
+    view.assertLastHtml("start=5,size=0");
     view.assertLoadingState(LoadingState.LOADING);
 
     // Page range same as data range.
     List<String> expectedData = createData(5, 10);
     presenter.setRowData(5, createData(5, 10));
-    assertEquals(10, presenter.getRowData().size());
-    assertEquals(expectedData, presenter.getRowData());
+    assertPresenterRowData(expectedData, presenter);
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=5,size=10");
@@ -1086,8 +1242,8 @@
 
     // Data range past page end.
     presenter.setRowData(15, createData(15, 5));
-    assertEquals(10, presenter.getRowData().size());
-    assertEquals(expectedData, presenter.getRowData());
+    assertPresenterRowData(expectedData, presenter);
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(false);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml(null);
@@ -1095,8 +1251,8 @@
 
     // Data range before page start.
     presenter.setRowData(0, createData(0, 5));
-    assertEquals(10, presenter.getRowData().size());
-    assertEquals(expectedData, presenter.getRowData());
+    assertPresenterRowData(expectedData, presenter);
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(false);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml(null);
@@ -1104,6 +1260,47 @@
   }
 
   /**
+   * Test that modifying more than 30% of the rows forces a full redraw.
+   */
+  public void testSetRowValuesRequiresRedraw() {
+    HasData<String> listView = new MockHasData<String>();
+    MockView<String> view = new MockView<String>();
+    HasDataPresenter<String> presenter = new HasDataPresenter<String>(listView,
+        view, 100, null);
+
+    // Initialize 100% of the rows.
+    populatePresenter(presenter);
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertReplaceChildrenCalled(false);
+
+    // Modify 30% of the rows.
+    presenter.setRowData(0, createData(0, 30));
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(false);
+    view.assertReplaceChildrenCalled(true);
+
+    // Modify 31% of the rows.
+    presenter.setRowData(0, createData(0, 31));
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertReplaceChildrenCalled(false);
+
+    /*
+     * Modify 4 rows in a 5 row table. This should NOT require a redraw because
+     * it is less than the minimum threshold.
+     */
+    presenter.setRowCount(5, true);
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertReplaceChildrenCalled(false);
+    presenter.setRowData(0, createData(0, 4));
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(false);
+    view.assertReplaceChildrenCalled(true);
+  }
+
+  /**
    * As an optimization, the presenter does not replace the rendered string if
    * the rendered string is identical to the previously rendered string. This is
    * useful for tables that refresh on an interval.
@@ -1118,6 +1315,7 @@
     // Initialize some data.
     presenter.setVisibleRange(new Range(0, 10));
     presenter.setRowData(0, createData(0, 10));
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=0,size=10");
@@ -1125,6 +1323,7 @@
 
     // Set the same data over the entire range.
     presenter.setRowData(0, createData(0, 10));
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(false);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml(null);
@@ -1149,14 +1348,55 @@
     expectedData.add(0, null);
     presenter.setVisibleRange(new Range(0, 10));
     presenter.setRowData(5, createData(5, 3));
-    assertEquals(8, presenter.getRowData().size());
-    assertEquals(expectedData, presenter.getRowData());
+    assertPresenterRowData(expectedData, presenter);
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=0,size=8");
     view.assertLoadingState(LoadingState.PARTIALLY_LOADED);
   }
 
+  public void testSetSelectionModel() {
+    HasData<String> listView = new MockHasData<String>();
+    MockView<String> view = new MockView<String>();
+    HasDataPresenter<String> presenter = new HasDataPresenter<String>(listView,
+        view, 10, null);
+    assertNull(presenter.getSelectionModel());
+
+    // Initialize some data.
+    presenter.setVisibleRange(new Range(0, 10));
+    populatePresenter(presenter);
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(true);
+    view.assertReplaceChildrenCalled(false);
+    view.assertLastHtml("start=0,size=10");
+
+    // Set the selection model.
+    SelectionModel<String> model = new MockSelectionModel<String>(null);
+    model.setSelected("test 0", true);
+    presenter.setSelectionModel(model);
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(false);
+    view.assertReplaceChildrenCalled(true);
+    view.assertLastHtml("start=0,size=1");
+
+    // Select something.
+    model.setSelected("test 2", true);
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(false);
+    view.assertReplaceChildrenCalled(true);
+    view.assertLastHtml("start=2,size=1");
+
+    // Set selection model to null.
+    presenter.setSelectionModel(null);
+    presenter.flush();
+    view.assertReplaceAllChildrenCalled(false);
+    view.assertReplaceChildrenCalled(true);
+    view.assertLastHtml("start=0,size=1");
+    view.assertLastHtml("start=2,size=1");
+    view.assertLastHtml(null);
+  }
+
   public void testSetVisibleRange() {
     HasData<String> listView = new MockHasData<String>();
     MockView<String> view = new MockView<String>();
@@ -1166,7 +1406,8 @@
     // Set the range the first time.
     presenter.setVisibleRange(new Range(0, 100));
     assertEquals(new Range(0, 100), presenter.getVisibleRange());
-    assertEquals(0, presenter.getRowData().size());
+    assertEquals(0, presenter.getRowDataSize());
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(false);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml(null);
@@ -1175,11 +1416,28 @@
     // Set the range to the same value.
     presenter.setVisibleRange(new Range(0, 100));
     assertEquals(new Range(0, 100), presenter.getVisibleRange());
-    assertEquals(0, presenter.getRowData().size());
+    assertEquals(0, presenter.getRowDataSize());
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(false);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml(null);
     view.assertLoadingState(LoadingState.LOADING);
+
+    // Set the start to a negative value.
+    try {
+      presenter.setVisibleRange(new Range(-1, 100));
+      fail("Expected IllegalArgumentException");
+    } catch (IllegalArgumentException e) {
+      // Expected.
+    }
+
+    // Set the length to a negative value.
+    try {
+      presenter.setVisibleRange(new Range(0, -100));
+      fail("Expected IllegalArgumentException");
+    } catch (IllegalArgumentException e) {
+      // Expected.
+    }
   }
 
   public void testSetVisibleRangeAndClearDataDifferentRange() {
@@ -1200,7 +1458,8 @@
     presenter.setVisibleRange(new Range(5, 10));
     presenter.setRowData(5, createData(5, 10));
     assertEquals(new Range(5, 10), presenter.getVisibleRange());
-    assertEquals(10, presenter.getRowData().size());
+    assertEquals(10, presenter.getRowDataSize());
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=5,size=10");
@@ -1210,7 +1469,8 @@
     // Set a different range.
     presenter.setVisibleRangeAndClearData(new Range(0, 10), false);
     assertEquals(new Range(0, 10), presenter.getVisibleRange());
-    assertEquals(0, presenter.getRowData().size());
+    assertEquals(0, presenter.getRowDataSize());
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=0,size=0");
@@ -1235,7 +1495,8 @@
     // Set some initial data.
     presenter.setRowData(0, createData(0, 10));
     assertEquals(new Range(0, 10), presenter.getVisibleRange());
-    assertEquals(10, presenter.getRowData().size());
+    assertEquals(10, presenter.getRowDataSize());
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=0,size=10");
@@ -1245,7 +1506,8 @@
     // Set the same range.
     presenter.setVisibleRangeAndClearData(new Range(0, 10), false);
     assertEquals(new Range(0, 10), presenter.getVisibleRange());
-    assertEquals(0, presenter.getRowData().size());
+    assertEquals(0, presenter.getRowDataSize());
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=0,size=0");
@@ -1270,7 +1532,8 @@
     // Set some initial data.
     presenter.setRowData(0, createData(0, 10));
     assertEquals(new Range(0, 10), presenter.getVisibleRange());
-    assertEquals(10, presenter.getRowData().size());
+    assertEquals(10, presenter.getRowDataSize());
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=0,size=10");
@@ -1280,7 +1543,8 @@
     // Set the same range.
     presenter.setVisibleRangeAndClearData(new Range(0, 10), true);
     assertEquals(new Range(0, 10), presenter.getVisibleRange());
-    assertEquals(0, presenter.getRowData().size());
+    assertEquals(0, presenter.getRowDataSize());
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=0,size=0");
@@ -1298,8 +1562,9 @@
     presenter.setVisibleRange(new Range(0, 10));
     assertEquals(new Range(0, 10), presenter.getVisibleRange());
     presenter.setRowData(0, createData(0, 10));
-    assertEquals(10, presenter.getRowData().size());
-    assertEquals("test 0", presenter.getRowData().get(0));
+    assertEquals(10, presenter.getRowDataSize());
+    assertEquals("test 0", presenter.getRowDataValue(0));
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=0,size=10");
@@ -1308,8 +1573,9 @@
     // Decrease the page size.
     presenter.setVisibleRange(new Range(0, 8));
     assertEquals(new Range(0, 8), presenter.getVisibleRange());
-    assertEquals(8, presenter.getRowData().size());
-    assertEquals("test 0", presenter.getRowData().get(0));
+    assertEquals(8, presenter.getRowDataSize());
+    assertEquals("test 0", presenter.getRowDataValue(0));
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=0,size=8");
@@ -1326,8 +1592,9 @@
     presenter.setVisibleRange(new Range(10, 30));
     assertEquals(new Range(10, 30), presenter.getVisibleRange());
     presenter.setRowData(10, createData(0, 10));
-    assertEquals(10, presenter.getRowData().size());
-    assertEquals("test 0", presenter.getRowData().get(0));
+    assertEquals(10, presenter.getRowDataSize());
+    assertEquals("test 0", presenter.getRowDataValue(0));
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=10,size=10");
@@ -1336,10 +1603,11 @@
     // Decrease the start index.
     presenter.setVisibleRange(new Range(8, 30));
     assertEquals(new Range(8, 30), presenter.getVisibleRange());
-    assertEquals(12, presenter.getRowData().size());
-    assertEquals(null, presenter.getRowData().get(0));
-    assertEquals(null, presenter.getRowData().get(1));
-    assertEquals("test 0", presenter.getRowData().get(2));
+    assertEquals(12, presenter.getRowDataSize());
+    assertEquals(null, presenter.getRowDataValue(0));
+    assertEquals(null, presenter.getRowDataValue(1));
+    assertEquals("test 0", presenter.getRowDataValue(2));
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=8,size=12");
@@ -1356,8 +1624,9 @@
     presenter.setVisibleRange(new Range(0, 10));
     assertEquals(new Range(0, 10), presenter.getVisibleRange());
     presenter.setRowData(0, createData(0, 10));
-    assertEquals(10, presenter.getRowData().size());
-    assertEquals("test 0", presenter.getRowData().get(0));
+    assertEquals(10, presenter.getRowDataSize());
+    assertEquals("test 0", presenter.getRowDataValue(0));
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=0,size=10");
@@ -1366,8 +1635,9 @@
     // Increase the page size.
     presenter.setVisibleRange(new Range(0, 20));
     assertEquals(new Range(0, 20), presenter.getVisibleRange());
-    assertEquals(10, presenter.getRowData().size());
-    assertEquals("test 0", presenter.getRowData().get(0));
+    assertEquals(10, presenter.getRowDataSize());
+    assertEquals("test 0", presenter.getRowDataValue(0));
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(false);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml(null);
@@ -1384,8 +1654,9 @@
     presenter.setVisibleRange(new Range(0, 20));
     assertEquals(new Range(0, 20), presenter.getVisibleRange());
     presenter.setRowData(0, createData(0, 10));
-    assertEquals(10, presenter.getRowData().size());
-    assertEquals("test 0", presenter.getRowData().get(0));
+    assertEquals(10, presenter.getRowDataSize());
+    assertEquals("test 0", presenter.getRowDataValue(0));
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=0,size=10");
@@ -1394,8 +1665,9 @@
     // Increase the start index.
     presenter.setVisibleRange(new Range(2, 20));
     assertEquals(new Range(2, 20), presenter.getVisibleRange());
-    assertEquals(8, presenter.getRowData().size());
-    assertEquals("test 2", presenter.getRowData().get(0));
+    assertEquals(8, presenter.getRowDataSize());
+    assertEquals("test 2", presenter.getRowDataValue(0));
+    presenter.flush();
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
     view.assertLastHtml("start=2,size=8");
@@ -1417,98 +1689,64 @@
   }
 
   /**
-   * If the cells depend on selection, the cells should be replaced.
+   * Test that the view is correctly updated if we move the page start back and
+   * forth in the same render loop.
    */
-  public void testSetSelectionModelDependOnSelection() {
+  public void testSetVisibleRangeResetPageStart() {
     HasData<String> listView = new MockHasData<String>();
     MockView<String> view = new MockView<String>();
-    view.setDependsOnSelection(true);
     HasDataPresenter<String> presenter = new HasDataPresenter<String>(listView,
         view, 10, null);
-    assertNull(presenter.getSelectionModel());
 
-    // Initialize some data.
-    presenter.setVisibleRange(new Range(0, 10));
+    // Initialize the view.
     populatePresenter(presenter);
+    presenter.flush();
+    view.assertLastHtml("start=0,size=10");
     view.assertReplaceAllChildrenCalled(true);
     view.assertReplaceChildrenCalled(false);
-    view.assertLastHtml("start=0,size=10");
 
-    // Set the selection model.
-    SelectionModel<String> model = new MockSelectionModel<String>(null);
-    model.setSelected("test 0", true);
-    presenter.setSelectionModel(model);
-    view.assertReplaceAllChildrenCalled(true);
-    view.assertReplaceChildrenCalled(false);
-    view.assertLastHtml("start=0,size=10");
-    view.assertOnUpdateSelectionFired(true);
-    view.assertSelectedRows();
-
-    // Select something.
-    model.setSelected("test 2", true);
-    view.assertReplaceAllChildrenCalled(true);
-    view.assertReplaceChildrenCalled(false);
-    view.assertLastHtml("start=0,size=10");
-    view.assertOnUpdateSelectionFired(true);
-    view.assertSelectedRows();
-
-    // Set selection model to null.
-    presenter.setSelectionModel(null);
-    view.assertReplaceAllChildrenCalled(true);
-    view.assertReplaceChildrenCalled(false);
-    view.assertLastHtml("start=0,size=10");
-    view.assertOnUpdateSelectionFired(true);
-    view.assertSelectedRows();
+    // Move pageStart to 2, then back to 0.
+    presenter.setVisibleRange(new Range(2, 8));
+    presenter.setVisibleRange(new Range(0, 10));
+    presenter.flush();
+    view.assertLastHtml("start=0,size=2");
+    view.assertReplaceAllChildrenCalled(false);
+    view.assertReplaceChildrenCalled(true);
   }
 
   /**
-   * If the cells do not depend on selection, the view should be told to update
-   * the cell container element.
+   * Assert that the expected List of values matches the row data in the
+   * specified {@link HasDataPresenter}.
+   * 
+   * @param <T> the data type
+   * @param expected the expected values
+   * @param presenter the presenter
    */
-  public void testSetSelectionModelDoesNotDependOnSelection() {
-    HasData<String> listView = new MockHasData<String>();
-    MockView<String> view = new MockView<String>();
-    HasDataPresenter<String> presenter = new HasDataPresenter<String>(listView,
-        view, 10, null);
-    assertNull(presenter.getSelectionModel());
+  private <T> void assertPresenterRowData(List<T> expected,
+      HasDataPresenter<T> presenter) {
+    assertEquals(expected.size(), presenter.getRowDataSize());
+    for (int i = 0; i < expected.size(); i++) {
+      assertEquals(expected.get(i), presenter.getRowDataValue(i));
+    }
+  }
 
-    // Initialize some data.
-    presenter.setVisibleRange(new Range(0, 10));
-    populatePresenter(presenter);
-    view.assertReplaceAllChildrenCalled(true);
-    view.assertReplaceChildrenCalled(false);
-    view.assertLastHtml("start=0,size=10");
-
-    // Set the selection model.
-    SelectionModel<String> model = new MockSelectionModel<String>(null);
-    model.setSelected("test 0", true);
-    presenter.setSelectionModel(model);
-    view.assertReplaceAllChildrenCalled(false);
-    view.assertReplaceChildrenCalled(false);
-    view.assertLastHtml(null);
-    view.assertOnUpdateSelectionFired(true);
-    view.assertSelectedRows(0);
-
-    // Select something.
-    model.setSelected("test 2", true);
-    view.assertReplaceAllChildrenCalled(false);
-    view.assertReplaceChildrenCalled(false);
-    view.assertLastHtml(null);
-    view.assertOnUpdateSelectionFired(true);
-    view.assertSelectedRows(0, 2);
-
-    // Set selection model to null.
-    presenter.setSelectionModel(null);
-    view.assertReplaceAllChildrenCalled(false);
-    view.assertReplaceChildrenCalled(false);
-    view.assertLastHtml(null);
-    view.assertOnUpdateSelectionFired(true);
-    view.assertSelectedRows();
+  /**
+   * Assert that the specified set contains specified values in order.
+   * 
+   * @param <T> the data type
+   * @param list the list to check
+   * @param values the expected values
+   */
+  private <T> void assertListContains(List<T> list, T... values) {
+    assertEquals(values.length, list.size());
+    for (int i = 0; i < values.length; i++) {
+      assertEquals(values[i], list.get(i));
+    }
   }
 
   /**
    * Create a list of data for testing.
-   *
+   * 
    * @param start the start index
    * @param length the length
    * @return a list of data
@@ -1523,7 +1761,7 @@
 
   /**
    * Populate the entire range of a presenter.
-   *
+   * 
    * @param presenter the presenter
    */
   private void populatePresenter(HasDataPresenter<String> presenter) {