Bug 161805 [Viewers] JFace TreeViewer collapses node when sibbling removed
3.2 1. Use the Eclipse Wizard to produce a plugin with a tree viewer view. 2. Paste the modified SampleView.java - this looks like the left part of the attached screenshot 3. Click on the top node Parent1 and type - 4. TreeViewer.remove is called to remove Parent 1. TreeViewer.refresh is called - this looks like the right part of the attached screenshot Wrong: node Parent 4 is now collapsed. Expectation Parent 4 is still expanded. Is there any workaround? Am I misusing your API? Note. The snippet is almost identical to the code generated by PDE for plugin / view / Tree Viewer. Here is the extra code in createPartControl: viewer.getTree().addKeyListener(new KeyListener() { public void keyReleased(KeyEvent e) { // TODO Auto-generated method stub } public void keyPressed(KeyEvent e) { if (e.character == '-') { TreeParent parent = (TreeParent) ((IStructuredSelection)viewer.getSelection()).toArray()[0]; parent.getParent().removeChild(parent); viewer.refresh(); } if (e.character == '+') { TreeParent parent = (TreeParent) ((IStructuredSelection)viewer.getSelection()).toArray()[0]; parent.addChild(new TreeParent(new Date().toString())); } } });
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
CustomHashtable expandedTreePaths, Widget widget,
			TreePath currentPath) {
		Item[] items = getChildren(widget);
		for (int i = 0; i < items.length; i++) {
			Item item = items[i];
			Object data = item.getData();
			TreePath childPath = data == null ? null : currentPath
					.createChildPath(data);
			if (data != null && childPath != null) {
				
				
				boolean expanded = expandedTreePaths.remove(childPath) != null;
				if (expanded != getExpanded(item)) {
					if (expanded) {
						createChildren(item);
					}
					setExpanded(item, expanded);
				}
			}
			internalSetExpandedTreePaths(expandedTreePaths, item, childPath);
		}
	}
	/**
	 * Return whether the tree node representing the given element or path can
	 * be expanded. Clients should query expandablity by path if the viewer's
	 * content provider is an {@link ITreePathContentProvider}.
	 * <p>
	 * The default implementation of this framework method calls
	 * <code>hasChildren</code> on this viewer's content provider. It may be
	 * overridden if necessary.