如果您显示过Tree的ToolTip，会发现这个tooltip离鼠标太远了；而且也无法跟随鼠标一起移动；最重要的是，如果想动态更改tooltip也很麻烦。

还是自定义ToolTip灵活：

1. 设置tree.toolTipFunction，关闭默认的tooltip

tree.toolTipFunction = function(element:IData):String {	return null;}

2. 监听mousemove事件，动态显示、隐藏以及更新tooltip

tree.addEventListener(MouseEvent.MOUSE_MOVE, function(e:MouseEvent):void {	handleMouseMove(e);});

3. 由于tree.getTreeDataByMouseEvent方法中，即使鼠标在空白处也有返回值，所以需要特殊处理一下，判断鼠标是否在icon或者text上：

private function showToolTip():Boolean {	var obj:InteractiveObject = null;	var mousePoint:Point = new Point(stage.mouseX, stage.mouseY);	var objects:Array = stage.getObjectsUnderPoint(mousePoint);	for (var i:int = objects.length-1; i>=0; i--) {		if (objects[i] is InteractiveObject) {			obj = objects[i] as InteractiveObject;			break;		} else {			if (objects[i] is Shape && (objects[i] as Shape).parent) {				obj = (objects[i] as Shape).parent;				break;			}		}	}	return obj is UIComponent || obj is UITextField;}

效果如下：

完整代码： 

     	
      		=0; i--) {					if (objects[i] is InteractiveObject) {						obj = objects[i] as InteractiveObject;						break;					} else {						if (objects[i] is Shape && (objects[i] as Shape).parent) {							obj = (objects[i] as Shape).parent;							break;						}					}				}				return obj is UIComponent || obj is UITextField;			}		]]>	
      	
      
     

 完整代码见附件：