/** * @param child the child node the hook should be propagated to. * @return returns the new hook or null if there is already such a hook. */ protected PermanentNodeHook propagate(MindMapNode child) { PermanentNodeHook hook = (PermanentNodeHook) getMindMapController().createNodeHook(getName(), child, getMap()); // invocation: child.invokeHook(hook); return hook; }