Gadget: Draggable
Bits: 0 - Set means warn of drag start using Draggable_DragStarted.
1 - Set means draggable containg a sprite.
2 - Set means draggable containg text.
3-5 - Draggable type:
0 - Drag only.
1 - Click, drag, doubleclick.
2 - Click selects, doubleclick, drag.
6 - Set means deliver drag ended events as Toolbox id's.
7 - Set means dragged object has a drop shadow (if solid).
8 - Set means dragged object is not dithered (if solid).
