We started off our tour of Ext.dd
by looking at how individual nodes could be moved around the screen and placed in designated containers. From there, we described the methods used to enable dragging for many nodes at once, and how these could be dropped within containers with child nodes.
When you're dealing with lots of draggable elements, there's a third facility that can be used to make sure that your nodes behave in the way you'd expect: drag-drop groups. DragSource, DragZone, DropTarget
, and DropZone
accept the configuration option ddGroup
that in turn accepts a string identifier indicating which group you'd like to assign your instance to.
But what does this configuration option actually do, in practical terms, and what new features does it provide for your applications? Well, strictly speaking, it means that a drag-drop class instance will only be able to interact with other drag-drop instances in the same group, but that's a rather dry way of explaining it. Let...