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 widget
	 * @param sorter
	 *            The sorter to use.
	 * @param startIndex
	 *            the start index to start search for position from this allows
	 *            optimising search for multiple elements that are sorted
	 *            themself.
	 * @param element
	 *            element to find position for.
	 * @param currentSize
	 *            the current size of the collection
	 * @return the index to use when inserting the element.
	 * 
	 */
	/**
	 * Returns the index where the item should be inserted.
	 * 
	 * @param parent
	 *            The parent widget the element will be inserted into.
	 * @param element
	 *            The element to insert.
	 * @return int
	 */
	protected int indexForElement(Widget parent, Object element) {
		ViewerComparator comparator = getComparator();
		TreePath parentPath = internalGetSorterParentPath(parent, comparator);
		Item[] items = getChildren(parent);
		int count = items.length;
		if (comparator == null) {