user/test/com/google/gwt/user/client/ui/TreeTest.java - gwt - Git at Google

 /*
  * Copyright 2008 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
  * License for the specific language governing permissions and limitations under
  * the License.
  */
 package com.google.gwt.user.client.ui;

 import com.google.gwt.junit.client.GWTTestCase;
 import com.google.gwt.safehtml.shared.SafeHtmlUtils;
 import com.google.gwt.user.client.DOM;
 import com.google.gwt.user.client.Element;

 import java.util.Iterator;

 /**
  * Tests the Tree widget.
  */
 public class TreeTest extends GWTTestCase {

   private static final String html = "<b>hello</b><i>world</i>";

   static class Adder implements HasWidgetsTester.WidgetAdder {
     @Override
     public void addChild(HasWidgets container, Widget child) {
       ((Tree) container).addItem(child);
     }
   }

   @Override
   public String getModuleName() {
     return "com.google.gwt.user.DebugTest";
   }

   /**
    * Test for {@link Tree#add(IsWidget)}.
    */
   public void testAddAsIsWidget() {
     Tree t = createTree();
     Widget widget = new Label("foo");

     // IsWidget cast to call the overloaded version
     t.add((IsWidget) widget);

     assertEquals("The number of items should be 1", 1, t.getItemCount());
     assertSame(widget, t.getItem(0).getWidget());
   }

   /**
    * Ensures that {@link Tree#add(Widget)} does <b>NOT</b> throws a
    * {@link NullPointerException} when the Widget argument is <code>null</code>,
    * for stupidity consistency with add(Widget).
    */
   public void testAddNullAsIsWidget() {
     Tree t = createTree();
     // IsWidget reference to call the overload version
     IsWidget widget = null;

     t.add(widget);
     // ta da...
   }

   /**
    * Test for {@link Tree#addItem(IsTreeItem)}.
    */
   public void testAddItemIsTreeItem() {
     Tree t = createTree();
     TreeItem item = new TreeItem("hello");
     t.addItem((IsTreeItem) item);
     assertEquals(1, t.getItemCount());
     assertSame(item, t.getItem(0));
   }

   public void testAddItemSafeHtml() {
     Tree t = createTree();
     TreeItem item = t.addItem(SafeHtmlUtils.fromSafeConstant(html));
     assertEquals(html, item.getHTML().toLowerCase());
   }

   /**
    * Test for {@link Tree#addTextItem(String)}.
    */
   public void testAddTextItem() {
     Tree t = createTree();
     String text = "Some<br>text";
     TreeItem item = t.addTextItem(text);
     assertEquals(text, item.getText());
     // Safari 3 leaves > in the HTML
     String html = item.getHTML().replace(">", "&gt;");
     assertEquals("Some&lt;br&gt;text", html);
   }

   public void testAttachDetachOrder() {
     HasWidgetsTester.testAll(createTree(), new Adder(), true);
   }

   public void testClear() {
     Tree t = createTree();
     // Adding widget to end of tree, widgets still have their parents set
     // correctly.
     TreeItem a = new TreeItem("a");
     TreeItem b = new TreeItem("b");
     TreeItem c = new TreeItem("c");
     TreeItem d = new TreeItem();
     TreeItem e = new TreeItem();
     Label dLabel = new Label("d");
     Label eLabel = new Label("e");
     d.setWidget(dLabel);
     d.addItem(e);
     c.addItem(d);
     b.addItem(c);
     a.addItem(b);
     t.addItem(a);
     t.addItem("hello");
     t.addItem(eLabel);
     t.clear();
     assertFalse(t.treeItemIterator().hasNext());
     assertEquals(0, t.getChildWidgets().size());
   }

   public void testDebugId() {
     Tree tree = createTree();
     TreeItem top0 = tree.addItem("top0");
     TreeItem top1 = tree.addItem("top1");
     TreeItem top2 = tree.addItem("top2");
     TreeItem top3 = tree.addItem("top3");
     TreeItem bottom0 = top3.addItem("bottom0");
     TreeItem bottom1 = top3.addItem("bottom1");
     TreeItem bottom2 = top3.addItem("bottom2");

     // Check tree items deep
     tree.ensureDebugId("myTree");
     UIObjectTest.assertDebugId("myTree", tree.getElement());
     UIObjectTest.assertDebugId("myTree-root-child0", top0.getElement());
     UIObjectTest.assertDebugId("myTree-root-child1", top1.getElement());
     UIObjectTest.assertDebugId("myTree-root-child2", top2.getElement());
     UIObjectTest.assertDebugId("myTree-root-child3", top3.getElement());
     UIObjectTest.assertDebugId("myTree-root-child3-child0",
         bottom0.getElement());
     UIObjectTest.assertDebugId("myTree-root-child3-child1",
         bottom1.getElement());
     UIObjectTest.assertDebugId("myTree-root-child3-child2",
         bottom2.getElement());

     // Check tree item sub elements
     UIObjectTest.assertDebugId("myTree-root-child0-content",
         top0.getContentElem());

     UIObjectTest.assertDebugId("myTree-root-child3-image",
         top3.getImageHolderElement());
   }

   public void testInsertSameItemRepeatedly() {
     Tree t = createTree();
     TreeItem ti = new TreeItem();
     TreeItem wti = new TreeItem();
     wti.setWidget(new Label("label"));
     for (int i = 0; i < 10; i++) {
       t.addItem(ti);
       t.addItem(wti);
     }
     assertEquals(2, t.getItemCount());
     assertEquals(ti, t.getItem(0));
     assertEquals(wti, t.getItem(1));
   }

   public void testInsertItemSafeHtml() {
     Tree t = createTree();
     TreeItem item = t.insertItem(0, SafeHtmlUtils.fromSafeConstant(html));
     assertEquals(html, item.getHTML().toLowerCase());
   }

   public void testInsertTextItem() {
     Tree t = createTree();
     String text = "Some<br>text";
     TreeItem item = t.insertTextItem(0, text);
     assertEquals(text, item.getText());
     // Safari 3 leaves > in the HTML
     String html = item.getHTML().replace(">", "&gt;");
     assertEquals("Some&lt;br&gt;text", html);
   }

   public void testIterator() {
     Tree tree = createTree();
     Iterator<TreeItem> iter = tree.treeItemIterator();
     assertFalse(iter.hasNext());
     TreeItem a = tree.addItem("a");
     TreeItem b = tree.addItem("b");
     TreeItem c = tree.addItem("c");

     Iterator<TreeItem> iter2 = tree.treeItemIterator();
     assertEquals(a, iter2.next());
     assertEquals(b, iter2.next());
     assertEquals(c, iter2.next());
     assertFalse(iter2.hasNext());

     TreeItem a_a = a.addItem("a_a");
     TreeItem a_a_a = a_a.addItem("a_a_a");
     TreeItem a_a_b = a_a.addItem("a_a_b");

     Iterator<TreeItem> iter3 = tree.treeItemIterator();
     assertEquals(a, iter3.next());
     assertEquals(a_a, iter3.next());
     assertEquals(a_a_a, iter3.next());
     assertEquals(a_a_b, iter3.next());
     assertEquals(b, iter3.next());
     assertEquals(c, iter3.next());
     assertFalse(iter3.hasNext());
   }

   public void testNulls() {
     // Checking for setting the widget null then clearing the tree.
     Tree t = createTree();
     TreeItem item = new TreeItem();
     item.setWidget(null);
     t.clear();

     TreeItem a = t.addItem("");
     TreeItem b = t.addItem(new Label("b"));
     a.setWidget(null);
     b.setWidget(null);
   }

   public void testRemove() {
     Tree t = createTree();
     TreeItem item = t.addItem("a");
     TreeItem itemb = t.addItem("b");
     t.setSelectedItem(item);
     assertEquals(item, t.getSelectedItem());
     item.remove();
     assertNull(t.getSelectedItem());
     Iterator<TreeItem> iter = t.treeItemIterator();
     assertTrue(iter.hasNext());
     iter.next();
     assertFalse(iter.hasNext());
     t.removeItem(itemb);
     assertNull(t.getSelectedItem());
     Iterator<TreeItem> iter2 = t.treeItemIterator();
     assertFalse(iter2.hasNext());
   }

   /**
    * Test for {@link Tree#removeItem(IsTreeItem)}.
    */
   public void testRemoveIsTreeItem() {
     Tree t = createTree();
     TreeItem itemA = t.addItem("a");
     TreeItem itemB = t.addItem("b");
     // initial state
     assertEquals(2, t.getItemCount());
     assertSame(itemA, t.getItem(0));
     assertSame(itemB, t.getItem(1));
     // remove "itemA" as wrapper
     t.removeItem((IsTreeItem) itemA);
     assertEquals(1, t.getItemCount());
     assertSame(itemB, t.getItem(0));
     // ignore null
     t.removeItem((IsTreeItem) null);
   }

   /**
    * Test for {@link Tree#removeItems()}.
    */
   public void testRemoveItems() {
     Tree t = createTree();
     TreeItem itemA = t.addItem("a");
     TreeItem itemB = t.addItem("b");
     // initial state
     assertEquals(2, t.getItemCount());
     assertSame(itemA, t.getItem(0));
     assertSame(itemB, t.getItem(1));
     // do remove
     t.removeItems();
     assertEquals(0, t.getItemCount());
   }

   public void testRootAdd() {
     Tree t = createTree();
     Label l = new Label("hello");
     t.add(l);
     assertEquals(t, l.getParent());
   }

   public void testRootInsert() {
     Tree t = createTree();
     TreeItem b = t.addItem("b");
     assertEquals(1, t.getItemCount());
     assertEquals(b, t.getItem(0));

     // Insert at zero.
     TreeItem a = t.insertItem(0, "a");
     assertEquals(2, t.getItemCount());
     assertEquals(a, t.getItem(0));
     assertEquals(b, t.getItem(1));
     assertEquals(a.getElement().getNextSiblingElement(), b.getElement());

     // Insert at end.
     TreeItem d = t.insertItem(2, new Label("d"));
     assertEquals(3, t.getItemCount());
     assertEquals(a, t.getItem(0));
     assertEquals(b, t.getItem(1));
     assertEquals(d, t.getItem(2));
     assertEquals(b.getElement().getNextSiblingElement(), d.getElement());

     // Insert in the middle.
     TreeItem c = new TreeItem("c");
     t.insertItem(2, c);
     assertEquals(4, t.getItemCount());
     assertEquals(a, t.getItem(0));
     assertEquals(b, t.getItem(1));
     assertEquals(c, t.getItem(2));
     assertEquals(d, t.getItem(3));
     assertEquals(b.getElement().getNextSiblingElement(), c.getElement());
   }

   public void testRootInsertInvalidIndex() {
     Tree t = createTree();
     t.addItem("a");
     t.addItem("b");
     t.addItem("c");

     // Insert at -1.
     try {
       t.insertItem(-1, "illegal");
       fail("Expected IndexOutOfBoundsException");
     } catch (IndexOutOfBoundsException e) {
       // Expected.
     }

     // Insert past the end.
     try {
       t.insertItem(4, "illegal");
       fail("Expected IndexOutOfBoundsException");
     } catch (IndexOutOfBoundsException e) {
       // Expected.
     }
   }

   public void testSwap() {
     Tree t = createTree();

     // Start with text.
     TreeItem item = t.addItem("hello");
     String inner = DOM.getInnerHTML(item.getContentElem());
     assertTrue(inner.indexOf("hello") >= 0);
     t.addItem(item);
     Widget goodbyeWidget = new Label("goodbye");
     item.setWidget(goodbyeWidget);
     String innerWidget = DOM.getInnerHTML(item.getContentElem());
     assertFalse(innerWidget.indexOf("hello") >= 0);

     // Start with widget.
     Widget hello = new Label("hello");
     TreeItem widgetItem = t.addItem(hello);
     assertTrue(DOM.getInnerHTML(widgetItem.getContentElem()).indexOf("hello") >= 0);
     widgetItem.setText("goodbye");
     assertFalse(DOM.getInnerHTML(widgetItem.getContentElem()).indexOf("hello") >= 0);
     assertTrue(DOM.getInnerHTML(widgetItem.getContentElem()).indexOf("goodbye") >= 0);
     assertNull(hello.getParent());

     // Move widget.
     widgetItem.addItem(item);
     assertEquals(t, goodbyeWidget.getParent());
     assertEquals(goodbyeWidget, item.getWidget());

     // Set back to text.
     item.setText("aloha");
     assertEquals("aloha", DOM.getInnerHTML(item.getContentElem()));
     assertNull(goodbyeWidget.getParent());
     assertNull(item.getWidget());
   }

   public void testTree() {
     // Simple widget
     Tree t = createTree();
     Label l = new Label("simple widget");
     TreeItem simple = new TreeItem(l);
     t.addItem(simple);

     // Adding test and widget
     TreeItem item = new TreeItem();
     t.addItem(item);
     item.setWidget(new Label("now widget"));
     Element elem = item.getContentElem();
     assertEquals(1, DOM.getChildCount(elem));

     // Add widget to existing tree.
     Label l2 = new Label("next widget");
     simple.setWidget(l2);
     assertEquals(t, l2.getParent());

     // Remove a tree item, make sure widget is removed from tree, but not tree
     // item.
     simple.remove();
     assertEquals(l2, simple.getWidget());
     assertNull(l2.getParent());

     // Adding widget to end of tree, widgets still have their parents set
     // correctly.
     TreeItem a = new TreeItem("a");
     TreeItem b = new TreeItem("b");
     TreeItem c = new TreeItem("c");
     TreeItem d = new TreeItem();
     TreeItem e = new TreeItem();
     Label dLabel = new Label("d");
     Label eLabel = new Label("e");
     d.setWidget(dLabel);
     d.addItem(e);
     c.addItem(d);
     b.addItem(c);
     a.addItem(b);
     t.addItem(a);
     assertEquals(t, dLabel.getParent());
     e.setWidget(eLabel);
     assertEquals(t, eLabel.getParent());

     // Tree inside of Tree.
     Tree childTree = createTree();
     t.addItem(new TreeItem(childTree));

     // Swap TreeItems to new Tree.
     childTree.addItem(c);
     assertEquals(childTree, dLabel.getParent());
     assertEquals(childTree, eLabel.getParent());

     // Make sure remove clears.
     d.remove();
     assertNull(dLabel.getParent());
     assertNull(eLabel.getParent());
     assertFalse(childTree.getChildWidgets().containsKey(eLabel.getParent()));
   }

   private Tree createTree() {
     return new Tree();
   }
 }
	/*
	* Copyright 2008 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
	* License for the specific language governing permissions and limitations under
	* the License.
	*/
	package com.google.gwt.user.client.ui;

	import com.google.gwt.junit.client.GWTTestCase;
	import com.google.gwt.safehtml.shared.SafeHtmlUtils;
	import com.google.gwt.user.client.DOM;
	import com.google.gwt.user.client.Element;

	import java.util.Iterator;

	/**
	* Tests the Tree widget.
	*/
	public class TreeTest extends GWTTestCase {

	private static final String html = "<b>hello</b><i>world</i>";

	static class Adder implements HasWidgetsTester.WidgetAdder {
	@Override
	public void addChild(HasWidgets container, Widget child) {
	((Tree) container).addItem(child);
	}
	}

	@Override
	public String getModuleName() {
	return "com.google.gwt.user.DebugTest";
	}

	/**
	* Test for {@link Tree#add(IsWidget)}.
	*/
	public void testAddAsIsWidget() {
	Tree t = createTree();
	Widget widget = new Label("foo");

	// IsWidget cast to call the overloaded version
	t.add((IsWidget) widget);

	assertEquals("The number of items should be 1", 1, t.getItemCount());
	assertSame(widget, t.getItem(0).getWidget());
	}

	/**
	* Ensures that {@link Tree#add(Widget)} does <b>NOT</b> throws a
	* {@link NullPointerException} when the Widget argument is <code>null</code>,
	* for stupidity consistency with add(Widget).
	*/
	public void testAddNullAsIsWidget() {
	Tree t = createTree();
	// IsWidget reference to call the overload version
	IsWidget widget = null;

	t.add(widget);
	// ta da...
	}

	/**
	* Test for {@link Tree#addItem(IsTreeItem)}.
	*/
	public void testAddItemIsTreeItem() {
	Tree t = createTree();
	TreeItem item = new TreeItem("hello");
	t.addItem((IsTreeItem) item);
	assertEquals(1, t.getItemCount());
	assertSame(item, t.getItem(0));
	}

	public void testAddItemSafeHtml() {
	Tree t = createTree();
	TreeItem item = t.addItem(SafeHtmlUtils.fromSafeConstant(html));
	assertEquals(html, item.getHTML().toLowerCase());
	}

	/**
	* Test for {@link Tree#addTextItem(String)}.
	*/
	public void testAddTextItem() {
	Tree t = createTree();
	String text = "Some<br>text";
	TreeItem item = t.addTextItem(text);
	assertEquals(text, item.getText());
	// Safari 3 leaves > in the HTML
	String html = item.getHTML().replace(">", ">");
	assertEquals("Some<br>text", html);
	}

	public void testAttachDetachOrder() {
	HasWidgetsTester.testAll(createTree(), new Adder(), true);
	}

	public void testClear() {
	Tree t = createTree();
	// Adding widget to end of tree, widgets still have their parents set
	// correctly.
	TreeItem a = new TreeItem("a");
	TreeItem b = new TreeItem("b");
	TreeItem c = new TreeItem("c");
	TreeItem d = new TreeItem();
	TreeItem e = new TreeItem();
	Label dLabel = new Label("d");
	Label eLabel = new Label("e");
	d.setWidget(dLabel);
	d.addItem(e);
	c.addItem(d);
	b.addItem(c);
	a.addItem(b);
	t.addItem(a);
	t.addItem("hello");
	t.addItem(eLabel);
	t.clear();
	assertFalse(t.treeItemIterator().hasNext());
	assertEquals(0, t.getChildWidgets().size());
	}

	public void testDebugId() {
	Tree tree = createTree();
	TreeItem top0 = tree.addItem("top0");
	TreeItem top1 = tree.addItem("top1");
	TreeItem top2 = tree.addItem("top2");
	TreeItem top3 = tree.addItem("top3");
	TreeItem bottom0 = top3.addItem("bottom0");
	TreeItem bottom1 = top3.addItem("bottom1");
	TreeItem bottom2 = top3.addItem("bottom2");

	// Check tree items deep
	tree.ensureDebugId("myTree");
	UIObjectTest.assertDebugId("myTree", tree.getElement());
	UIObjectTest.assertDebugId("myTree-root-child0", top0.getElement());
	UIObjectTest.assertDebugId("myTree-root-child1", top1.getElement());
	UIObjectTest.assertDebugId("myTree-root-child2", top2.getElement());
	UIObjectTest.assertDebugId("myTree-root-child3", top3.getElement());
	UIObjectTest.assertDebugId("myTree-root-child3-child0",
	bottom0.getElement());
	UIObjectTest.assertDebugId("myTree-root-child3-child1",
	bottom1.getElement());
	UIObjectTest.assertDebugId("myTree-root-child3-child2",
	bottom2.getElement());

	// Check tree item sub elements
	UIObjectTest.assertDebugId("myTree-root-child0-content",
	top0.getContentElem());

	UIObjectTest.assertDebugId("myTree-root-child3-image",
	top3.getImageHolderElement());
	}

	public void testInsertSameItemRepeatedly() {
	Tree t = createTree();
	TreeItem ti = new TreeItem();
	TreeItem wti = new TreeItem();
	wti.setWidget(new Label("label"));
	for (int i = 0; i < 10; i++) {
	t.addItem(ti);
	t.addItem(wti);
	}
	assertEquals(2, t.getItemCount());
	assertEquals(ti, t.getItem(0));
	assertEquals(wti, t.getItem(1));
	}

	public void testInsertItemSafeHtml() {
	Tree t = createTree();
	TreeItem item = t.insertItem(0, SafeHtmlUtils.fromSafeConstant(html));
	assertEquals(html, item.getHTML().toLowerCase());
	}

	public void testInsertTextItem() {
	Tree t = createTree();
	String text = "Some<br>text";
	TreeItem item = t.insertTextItem(0, text);
	assertEquals(text, item.getText());
	// Safari 3 leaves > in the HTML
	String html = item.getHTML().replace(">", ">");
	assertEquals("Some<br>text", html);
	}

	public void testIterator() {
	Tree tree = createTree();
	Iterator<TreeItem> iter = tree.treeItemIterator();
	assertFalse(iter.hasNext());
	TreeItem a = tree.addItem("a");
	TreeItem b = tree.addItem("b");
	TreeItem c = tree.addItem("c");

	Iterator<TreeItem> iter2 = tree.treeItemIterator();
	assertEquals(a, iter2.next());
	assertEquals(b, iter2.next());
	assertEquals(c, iter2.next());
	assertFalse(iter2.hasNext());

	TreeItem a_a = a.addItem("a_a");
	TreeItem a_a_a = a_a.addItem("a_a_a");
	TreeItem a_a_b = a_a.addItem("a_a_b");

	Iterator<TreeItem> iter3 = tree.treeItemIterator();
	assertEquals(a, iter3.next());
	assertEquals(a_a, iter3.next());
	assertEquals(a_a_a, iter3.next());
	assertEquals(a_a_b, iter3.next());
	assertEquals(b, iter3.next());
	assertEquals(c, iter3.next());
	assertFalse(iter3.hasNext());
	}

	public void testNulls() {
	// Checking for setting the widget null then clearing the tree.
	Tree t = createTree();
	TreeItem item = new TreeItem();
	item.setWidget(null);
	t.clear();

	TreeItem a = t.addItem("");
	TreeItem b = t.addItem(new Label("b"));
	a.setWidget(null);
	b.setWidget(null);
	}

	public void testRemove() {
	Tree t = createTree();
	TreeItem item = t.addItem("a");
	TreeItem itemb = t.addItem("b");
	t.setSelectedItem(item);
	assertEquals(item, t.getSelectedItem());
	item.remove();
	assertNull(t.getSelectedItem());
	Iterator<TreeItem> iter = t.treeItemIterator();
	assertTrue(iter.hasNext());
	iter.next();
	assertFalse(iter.hasNext());
	t.removeItem(itemb);
	assertNull(t.getSelectedItem());
	Iterator<TreeItem> iter2 = t.treeItemIterator();
	assertFalse(iter2.hasNext());
	}

	/**
	* Test for {@link Tree#removeItem(IsTreeItem)}.
	*/
	public void testRemoveIsTreeItem() {
	Tree t = createTree();
	TreeItem itemA = t.addItem("a");
	TreeItem itemB = t.addItem("b");
	// initial state
	assertEquals(2, t.getItemCount());
	assertSame(itemA, t.getItem(0));
	assertSame(itemB, t.getItem(1));
	// remove "itemA" as wrapper
	t.removeItem((IsTreeItem) itemA);
	assertEquals(1, t.getItemCount());
	assertSame(itemB, t.getItem(0));
	// ignore null
	t.removeItem((IsTreeItem) null);
	}

	/**
	* Test for {@link Tree#removeItems()}.
	*/
	public void testRemoveItems() {
	Tree t = createTree();
	TreeItem itemA = t.addItem("a");
	TreeItem itemB = t.addItem("b");
	// initial state
	assertEquals(2, t.getItemCount());
	assertSame(itemA, t.getItem(0));
	assertSame(itemB, t.getItem(1));
	// do remove
	t.removeItems();
	assertEquals(0, t.getItemCount());
	}

	public void testRootAdd() {
	Tree t = createTree();
	Label l = new Label("hello");
	t.add(l);
	assertEquals(t, l.getParent());
	}

	public void testRootInsert() {
	Tree t = createTree();
	TreeItem b = t.addItem("b");
	assertEquals(1, t.getItemCount());
	assertEquals(b, t.getItem(0));

	// Insert at zero.
	TreeItem a = t.insertItem(0, "a");
	assertEquals(2, t.getItemCount());
	assertEquals(a, t.getItem(0));
	assertEquals(b, t.getItem(1));
	assertEquals(a.getElement().getNextSiblingElement(), b.getElement());

	// Insert at end.
	TreeItem d = t.insertItem(2, new Label("d"));
	assertEquals(3, t.getItemCount());
	assertEquals(a, t.getItem(0));
	assertEquals(b, t.getItem(1));
	assertEquals(d, t.getItem(2));
	assertEquals(b.getElement().getNextSiblingElement(), d.getElement());

	// Insert in the middle.
	TreeItem c = new TreeItem("c");
	t.insertItem(2, c);
	assertEquals(4, t.getItemCount());
	assertEquals(a, t.getItem(0));
	assertEquals(b, t.getItem(1));
	assertEquals(c, t.getItem(2));
	assertEquals(d, t.getItem(3));
	assertEquals(b.getElement().getNextSiblingElement(), c.getElement());
	}

	public void testRootInsertInvalidIndex() {
	Tree t = createTree();
	t.addItem("a");
	t.addItem("b");
	t.addItem("c");

	// Insert at -1.
	try {
	t.insertItem(-1, "illegal");
	fail("Expected IndexOutOfBoundsException");
	} catch (IndexOutOfBoundsException e) {
	// Expected.
	}

	// Insert past the end.
	try {
	t.insertItem(4, "illegal");
	fail("Expected IndexOutOfBoundsException");
	} catch (IndexOutOfBoundsException e) {
	// Expected.
	}
	}

	public void testSwap() {
	Tree t = createTree();

	// Start with text.
	TreeItem item = t.addItem("hello");
	String inner = DOM.getInnerHTML(item.getContentElem());
	assertTrue(inner.indexOf("hello") >= 0);
	t.addItem(item);
	Widget goodbyeWidget = new Label("goodbye");
	item.setWidget(goodbyeWidget);
	String innerWidget = DOM.getInnerHTML(item.getContentElem());
	assertFalse(innerWidget.indexOf("hello") >= 0);

	// Start with widget.
	Widget hello = new Label("hello");
	TreeItem widgetItem = t.addItem(hello);
	assertTrue(DOM.getInnerHTML(widgetItem.getContentElem()).indexOf("hello") >= 0);
	widgetItem.setText("goodbye");
	assertFalse(DOM.getInnerHTML(widgetItem.getContentElem()).indexOf("hello") >= 0);
	assertTrue(DOM.getInnerHTML(widgetItem.getContentElem()).indexOf("goodbye") >= 0);
	assertNull(hello.getParent());

	// Move widget.
	widgetItem.addItem(item);
	assertEquals(t, goodbyeWidget.getParent());
	assertEquals(goodbyeWidget, item.getWidget());

	// Set back to text.
	item.setText("aloha");
	assertEquals("aloha", DOM.getInnerHTML(item.getContentElem()));
	assertNull(goodbyeWidget.getParent());
	assertNull(item.getWidget());
	}

	public void testTree() {
	// Simple widget
	Tree t = createTree();
	Label l = new Label("simple widget");
	TreeItem simple = new TreeItem(l);
	t.addItem(simple);

	// Adding test and widget
	TreeItem item = new TreeItem();
	t.addItem(item);
	item.setWidget(new Label("now widget"));
	Element elem = item.getContentElem();
	assertEquals(1, DOM.getChildCount(elem));

	// Add widget to existing tree.
	Label l2 = new Label("next widget");
	simple.setWidget(l2);
	assertEquals(t, l2.getParent());

	// Remove a tree item, make sure widget is removed from tree, but not tree
	// item.
	simple.remove();
	assertEquals(l2, simple.getWidget());
	assertNull(l2.getParent());

	// Adding widget to end of tree, widgets still have their parents set
	// correctly.
	TreeItem a = new TreeItem("a");
	TreeItem b = new TreeItem("b");
	TreeItem c = new TreeItem("c");
	TreeItem d = new TreeItem();
	TreeItem e = new TreeItem();
	Label dLabel = new Label("d");
	Label eLabel = new Label("e");
	d.setWidget(dLabel);
	d.addItem(e);
	c.addItem(d);
	b.addItem(c);
	a.addItem(b);
	t.addItem(a);
	assertEquals(t, dLabel.getParent());
	e.setWidget(eLabel);
	assertEquals(t, eLabel.getParent());

	// Tree inside of Tree.
	Tree childTree = createTree();
	t.addItem(new TreeItem(childTree));

	// Swap TreeItems to new Tree.
	childTree.addItem(c);
	assertEquals(childTree, dLabel.getParent());
	assertEquals(childTree, eLabel.getParent());

	// Make sure remove clears.
	d.remove();
	assertNull(dLabel.getParent());
	assertNull(eLabel.getParent());
	assertFalse(childTree.getChildWidgets().containsKey(eLabel.getParent()));
	}

	private Tree createTree() {
	return new Tree();
	}
	}