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/TreeViewer.java
/*
	 * (non-Javadoc) Method declared in Viewer.
	 */
	public Control getControl() {
		return tree;
	}
	/*
	 * (non-Javadoc) Method declared in AbstractTreeViewer.
	 */
	protected boolean getExpanded(Item item) {
		return ((TreeItem) item).getExpanded();
	}
	/**
	 * Returns the item at the given display-relative coordinates, or
	 * <code>null</code> if there is no item at that location.
	 * <p>
	 * The default implementation of this method returns <code>null</code>.
	 * </p>
	 * 
	 * @param x
	 *            horizontal coordinate
	 * @param y
	 *            vertical coordinate
	 * @return the item, or <code>null</code> if there is no item at the given
	 *         coordinates
	 */
	protected Item getItem(int x, int y) {
		return getTree().getItem(getTree().toControl(new Point(x, y)));
	}
	/*