Time for action – adding a double-click listener

Typically, a tree view is used to show content in a hierarchical manner. However, a tree on its own is not enough to be able to show all the details associated with an object. When the user double-clicks on an element, more details can be shown.

1. At the end of the create method in TimeZoneTreeView, register a lambda block that implements the IDoubleClickListener interface with the addDoubleClickListener method on the treeViewer. As with the example in Chapter 1, Creating Your First Plug-in, this will open a message dialog to verify that it works as expected:

   treeViewer.addDoubleClickListener(event -> {
       Viewer viewer = event.getViewer();
       Shell shell = viewer.getControl().getShell();
       MessageDialog.openInformation(shell, "Double click",
        "Double click detected");
   });

2. Run the target Eclipse instance, and open the Time Zone Tree View. Double-click on the tree, and a shell will be displayed with the message Double click detected....