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
/**
	 * Get the child for the widget at index. Note that the default
	 * implementation is not very efficient and should be overridden if this
	 * class is implemented.
	 *
	 * @param widget
	 *            the widget to check
	 * @param index
	 *            the index of the widget
	 * @return Item or <code>null</code> if widget is not a type that can
	 *         contain items.
	 *
	 * @throws ArrayIndexOutOfBoundsException
	 *             if the index is not valid.
	 * @since 3.1
	 */
	protected Item getChild(Widget widget, int index) {
		return getChildren(widget)[index];
	}
	/**
	 * Returns whether the given SWT item is expanded or collapsed.
	 *
	 * @param item
	 *            the item
	 * @return <code>true</code> if the item is considered expanded and
	 *         <code>false</code> if collapsed
	 */
	protected abstract boolean getExpanded(Item item);
	/**
	 * Returns a list of elements corresponding to expanded nodes in this