Adds to HTMLPanel:
- addAndReplaceElement()
- getElementById()
Patch by: jgw
Review by: scottb, knorton
Issues: 1616, 2357
git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@2701 8db76d5a-ed1c-0410-87a9-c151d255dfc7
diff --git a/user/src/com/google/gwt/user/client/ui/HTMLPanel.java b/user/src/com/google/gwt/user/client/ui/HTMLPanel.java
index 3e6a458..b2e9d03 100644
--- a/user/src/com/google/gwt/user/client/ui/HTMLPanel.java
+++ b/user/src/com/google/gwt/user/client/ui/HTMLPanel.java
@@ -26,6 +26,8 @@
*/
public class HTMLPanel extends ComplexPanel {
+ private static Element hiddenDiv;
+
/**
* A helper method for creating unique IDs for elements within dynamically-
* generated HTML. This is important because no two elements in a document
@@ -37,8 +39,6 @@
return DOM.createUniqueId();
}
- private Element hiddenDiv;
-
/**
* Creates an HTML panel with the specified HTML contents. Any element within
* this HTML that has a specified id can contain a child widget.
@@ -58,8 +58,7 @@
* @param id the id of the element within which it will be contained
*/
public void add(Widget widget, String id) {
- final Element elem = (isAttached()) ? DOM.getElementById(id)
- : attachToDomAndGetElement(id);
+ final Element elem = getElementById(id);
if (elem == null) {
throw new NoSuchElementException(id);
@@ -68,15 +67,35 @@
super.add(widget, elem);
}
- @Override
- protected void onLoad() {
- if (hiddenDiv != null) {
- // This widget's element has already been moved, just need to remove the
- // hidden DIV.
- DOM.removeChild(RootPanel.getBodyElement(), hiddenDiv);
- hiddenDiv = null;
+ /**
+ * Adds a child widget to the panel, replacing the HTML element specified by a
+ * given id.
+ *
+ * @param widget the widget to be added
+ * @param id the id of the element to be replaced by the widget
+ */
+ public void addAndReplaceElement(Widget widget, String id) {
+ final Element toReplace = getElementById(id);
+
+ if (toReplace == null) {
+ throw new NoSuchElementException(id);
}
- super.onLoad();
+
+ // Logic pulled from super.add(), replacing the element rather than adding.
+ widget.removeFromParent();
+ getChildren().add(widget);
+ toReplace.getParentNode().replaceChild(widget.getElement(), toReplace);
+ adopt(widget);
+ }
+
+ /**
+ * Finds an {@link Element element} within this panel by its id.
+ *
+ * @param id the id of the element to be found
+ * @return the element with the given id, or <code>null</code> if none is found
+ */
+ public Element getElementById(String id) {
+ return isAttached() ? DOM.getElementById(id) : attachToDomAndGetElement(id);
}
/**
diff --git a/user/test/com/google/gwt/user/client/ui/HTMLPanelTest.java b/user/test/com/google/gwt/user/client/ui/HTMLPanelTest.java
index 72494ec..8d6986d 100644
--- a/user/test/com/google/gwt/user/client/ui/HTMLPanelTest.java
+++ b/user/test/com/google/gwt/user/client/ui/HTMLPanelTest.java
@@ -15,8 +15,10 @@
*/
package com.google.gwt.user.client.ui;
+import com.google.gwt.dom.client.Node;
import com.google.gwt.junit.client.GWTTestCase;
import com.google.gwt.user.client.DOM;
+import com.google.gwt.user.client.Element;
/**
* Tests the HTMLPanel widget.
@@ -98,4 +100,34 @@
assertTrue(DOM.getNextSibling(ba.getElement()) == hp.getElement());
assertTrue(DOM.getNextSibling(hp.getElement()) == bb.getElement());
}
+
+ /**
+ * Ensures that addAndReplaceChild() puts the widget in exactly the right place in the DOM.
+ */
+ public void testAddAndReplaceElement() {
+ HTMLPanel hp = new HTMLPanel("<div id='parent'>foo<span id='placeholder'></span>bar</div>");
+
+ Button button = new Button("my button");
+ hp.addAndReplaceElement(button, "placeholder");
+
+ assertEquals("parent", button.getElement().getParentElement().getId());
+
+ Node prev = button.getElement().getPreviousSibling();
+ assertEquals("foo", prev.getNodeValue());
+
+ Node next = button.getElement().getNextSibling();
+ assertEquals("bar", next.getNodeValue());
+ }
+
+ public void testGetElementById() {
+ HTMLPanel hp = new HTMLPanel("foo<div id='toFind'>bar</div>baz");
+
+ // Get the element twice, once before and once after attachment.
+ Element elem0 = hp.getElementById("toFind");
+ RootPanel.get().add(hp);
+ Element elem1 = hp.getElementById("toFind");
+
+ // Make sure we got the same element in both cases.
+ assertEquals(elem0, elem1);
+ }
}
