DropContext

The DropContext class provides the context in which the dropping of a node occurs. You can use this to perform your own drag and drop validation on the tree. You do not ever instantiate this class, but instead retrieve a reference through the dropContext property of the AdvancedTree.

Property Name	Access	Class	Description	Value
position	public	uint	The position for the drop in relation to the node on which it was dropped. This will be a constant on the class, NULL, OVER_NODE or BETWEEN_NODES.
node	public	TreeNode	The node onto which the dragged node was dropped.
index	public	uint	The index position in the childnodes of the node onto which the dragged node was dropped at which the dropped node will be inserted.
NULL	static public	uint	This constant value specifies that there was no node onto which the dragged node was dropped. This should be viewed as an error condition.	0
OVER_NODE	static public	uint	This constant value specifies that the dragged node was dropped directly onto the node.	1
BETWEEN_NODES	static public	uint	This constant value specifies that the dragged node was dropped in between child nodes of the node.	2

DropContext is found in the com.flashloaded.ui.tree.drag package. An example of its use follows:

private function onDropPrecommit(event:TreeEvent):void {
  var dropContext:DropContext = _tree.dropContext;
  if (dropContext.position != DropContext.NULL) {
    // always add dropped nodes to end of childnodes
    if (dropContext.index > 0) {
      var draggedNode:TreeNode = event.node;
      var droppedOnNode:TreeNode = dropContext.node;
      event.preventDefault();
      var copiedNode:TreeNode = draggedNode.copy();
      _tree.removeNode(draggedNode);
      droppedOnNode.addNode(copiedNode);
    }
  }
}