public static interface IconView.ItemActivated

Emitted when an item in the IconView has been activated. Activation occurs when an item in the view is double-clicked, or when Space or Enter are pressed while an item is selected.

In general, you've got the TreeModel and especially its DataColumns visible, so to use IconView.ItemActivated you can just:

 final TreeModel model;
 final DataColumnString column;
 
 view.connect(new IconView.ItemActivated() {
     public void onItemActivated(IconView source, TreePath path) {
         final TreeIter row;
 
         row = model.getIter(path);
 
         ... = model.getValue(row, column);
     }
 });
 

Remember that TreeIters and TreePaths are not stable over changes to the model, so get on with using path right away.