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Is there a way to check if DisplayObject A is a descendant of DisplayObject B?

开发者 https://www.devze.com 2023-01-21 20:02 出处:网络
I would like to be able to quickly check if a given DisplayObject is a descendant (not in the inheritance sense - ie. child, grandchild, great-grandchild, great-great-grandchild, etc.) of another Disp

I would like to be able to quickly check if a given DisplayObject is a descendant (not in the inheritance sense - ie. child, grandchild, great-grandchild, great-great-grandchild, etc.) of another DisplayObject.

There doesn't seem to be a native way to do this and I can only think of two ways to achieve it:

  1. Create the mother of all nested loops. Seems a bit, I dunno, wrong?
  2. Dispatch a bubbling event at the 'child' and check if the potential 'parent' rece开发者_如何学Cives it.

Am trying the latter now, but would appreciate some input. I'd like to create a nice utility static function, eg:

static public function isDescendantOf(child:DisplayObject, parent:DisplayObjectContainer):Boolean { 

    var isDescendant: Boolean = false;

    // perform some magical 
    // check that returns true 
    // if it is a descendant

    return isDescendant;
}


Holy horned moose, event for that...

parent.contains(child);

See reference for DisplayObjectContainer.contains().


Ok I got it working, but it uses a nasty anonymous function.

Wonder if it can be improved?

static public function isDescendantOf(child:DisplayObject, parent:DisplayObjectContainer):Boolean {
    const HELLO:String = "hello";
    var isDescendant:Boolean = false;

    parent.addEventListener(HELLO, function(e:Event):void {
       isDescendant = true;
    });

    child.dispatchEvent(new Event(HELLO, true, false));
    return isDescendant;
}
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