Bug 270457 [Viewers] [regression] CheckBoxTreeViewer clears check state after collapseAll
Hi there :) In my RCP I've a CheckBoxTreeViewer that looses check states for invisible items. Turns out if a disable the collapseAll() call things go back to normal. So, in a tree like this: [x] root [x] sub a collapseAll expandAll will create this: [x] root [] sub Could still be my fault, feel free to have me try some workarounds or other tests that help you find the cause...
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
if (getExpanded(item)) {
				result.add(item);
			}
			internalCollectExpandedItems(result, item);
		}
	}
	/**
	 * Tries to create a path of tree items for the given element or tree path.
	 * This method recursively walks up towards the root of the tree and in the
	 * case of an element (rather than a tree path) assumes that
	 * <code>getParent</code> returns the correct parent of an element.
	 *
	 * @param elementOrPath
	 *            the element
	 * @param expand
	 *            <code>true</code> if all nodes on the path should be
	 *            expanded, and <code>false</code> otherwise
	 * @return Widget
	 */
	protected Widget internalExpand(Object elementOrPath, boolean expand) {
		if (elementOrPath == null) {
			return null;
		}
		Widget w = internalGetWidgetToSelect(elementOrPath);
		if (w == null) {
			if (equals(elementOrPath, getRoot())) { 
				return null;
			}
			
			Object parent = getParentElement(elementOrPath);