Simple tree to display item in a hierarchical way.
Start by creating a new application, with the desktop libraries and goldreflection or bluecrystal theme.
In this example we start with the ux3.Shell object as our desktop Application Shell. Use a ShellItem with position addContent and this will be the default content when you start the Shell. Place a Tree object as child to the ShellItem. The Tree should be bound to the public attribute from the application class (explained further down) and set an Ajax ID to identify the ajax request to SAP.
HowTo: Application Class