How to make Editor GUI like Mecanim Conditions/Transition boxes

Does anyone know what this GUI element is called?

Also if so, is there a easy way to code it? Or is this one of those things that’s not easy to get at, and I should probably look for a easier solution.
I’d like to use it to make a pretty list of GameObjects with a drop-down menu for setting a limited integer value.

15323-fancydraggableboxes.png

Thanks in advance!

The drop-downs are two EditorGUI.PopUp controls – probably implemented as EditorGUILayout.PopUp within a horizontal group.

As of Unity 4.5, this GUI has been exposed in namespace UnityEditorInternal as “ReorderableList”. It is currently undocumented.

See: