Bug 156537 [Viewers] Virtual tree viewer does not populate with initial children
I20060830-1650 When a tree viewer is created with the SWT.Vitrual flag and uses an ILazyTreeContentProvider, the viewew does not populate with the initial children in the model. The method TreeViewer.createChildren(Widget) only updates existing items if the parent (root)element has been mapped to data, and does not query the content provider for the number of children it has. Attached is a sample plug-in showing the problem. The tree "model" looks like this: root one two three When the input is set to the viewer ("root") a call is made to "createChildren", but the content provider is never used.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
* @param parent
	 *            the parent of the elements to remove
	 * @param elements
	 *            the elements to remove
	 * 
	 * @since 3.2
	 */
	public void remove(final Object parent, final Object[] elements) {
		assertElementsNotNull(elements);
		if (elements.length == 0) {
			return;
		}
		preservingSelection(new Runnable() {
			public void run() {
				internalRemove(parent, elements);
			}
		});
	}
	/**
	 * Removes the given element from the viewer. The selection is updated if
	 * necessary.
	 * <p>
	 * This method should be called (by the content provider) when a single
	 * element has been removed from the model, in order to cause the viewer to
	 * accurately reflect the model. This method only affects the viewer, not
	 * the model. Note that there is another method for efficiently processing
	 * the simultaneous removal of multiple elements.
	 * </p>
	 * 
	 * @param elementsOrTreePaths