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/CheckboxTreeViewer.java
Object data = item.getData();
            if (data != null) {
                fireCheckStateChanged(new CheckStateChangedEvent(this, data,
                        item.getChecked()));
            }
        } else {
			super.handleSelect(event);
		}
    }
    /**
     * Gathers the checked states of the given widget and its
     * descendents, following a pre-order traversal of the tree.
     *
     * @param result a writable list of elements (element type: <code>Object</code>)
     * @param widget the widget
     */
    private void internalCollectChecked(List result, Widget widget) {
        Item[] items = getChildren(widget);
        for (int i = 0; i < items.length; i++) {
            Item item = items[i];
            if (item instanceof TreeItem && ((TreeItem) item).getChecked()) {
                Object data = item.getData();
                if (data != null) {
					result.add(data);
				}
            }
            internalCollectChecked(result, item);
        }
    }
    /**