title: How to capture expand node event in SALV Tree?
body: <p>I've created an ALV tree view with use of the class <code>CL_SALV_TREE</code>.</p>
  
  <p>Everything works fine but I'd like to grap the event when a node is expanded, for filling in a function that automatically resizes the tree columns.</p>
  
  <p>My problem is, that the expanding event is the private method <code>HANDLE_EXPAND_NC</code> of class <code>CL_GUI_ALV_TREE</code> and I actually don't know how to capture this event. I'm open for any ideas and thanks for your time.</p>