title: Is there an event for collapsing a rich:tree node?
body: <p>I've finally managed to receive events if the user expands a node of my client side handled tree using the following method:</p>
  
  <pre><code>public void processExpansion(NodeExpandedEvent event) throws AbortProcessingException {
   if (event != null &amp;&amp; event.getSource() != null &amp;&amp; event.getSource() instanceof HtmlTree) {
    this.expandedNodes.add(((UITree) event.getSource()).getRowData());
   }
  }
  </code></pre>
  
  <p>I had to use #getRowData() because of the recursiveTreeNodesAdaptor.</p>
  
  <p>How can I get notification of nodes the user collapses again? I could not find an appropriate listener.</p>