Question

我在这里有一个问题。我正在做一个游戏，太空入侵者。它提示我一个错误

TypeError：错误＃2007：参数hitTestObject必须为非null。在flash.display :: DisplayObject / _hitTest（）在flash.display :: DisplayObject / hitTestObject（）在Enemy / eFrame（）

我希望你们中的任何人都可以帮助我。非常感谢你！

//This is the basic skeleton that all classes must have
package{
    //we have to import certain display objects and events
    import flash.display.MovieClip;
    import flash.events.*;
    //this just means that Enemy will act like a MovieClip
    public class Enemy extends MovieClip{
        //VARIABLES
        //this will act as the root of the document
        //so we can easily reference it within the class
        private var _root:Object;
        //how quickly the enemy will move
        private var speed:int = 5;
        //this function will run every time the Bullet is added
        //to the stage
        public function Enemy(){
            //adding events to this class
            //functions that will run only when the MC is added
            addEventListener(Event.ADDED, beginClass);
            //functions that will run on enter frame
            addEventListener(Event.ENTER_FRAME, eFrame);
        }
        private function beginClass(event:Event):void{
            _root = MovieClip(root);
        }









        private function eFrame(event:Event):void{
            //moving the bullet up screen
            y += speed;
            //making the bullet be removed if it goes off stage
            if(this.y > stage.stageHeight){
                removeEventListener(Event.ENTER_FRAME, eFrame);
                _root.removeChild(this);
            }

            //checking if it is touching any bullets
            //we will have to run a for loop because there will be multiple bullets
            for(var i:int = 0;i<_root.bulletContainer.numChildren;i++){
                //numChildren is just the amount of movieclips within 
                //the bulletContainer.

                //we define a variable that will be the bullet that we are currently
                //hit testing.
                var bulletTarget:MovieClip = _root.bulletContainer.getChildAt(i);


                //now we hit test
                if(hitTestObject(bulletTarget)){
                    //remove this from the stage if it touches a bullet
                    removeEventListener(Event.ENTER_FRAME, eFrame);
                    _root.removeChild(this);
                    //also remove the bullet and its listeners
                    _root.bulletContainer.removeChild(bulletTarget);
                    bulletTarget.removeListeners();
                    //up the score
                    _root.score += 5;
                }
            }

            //hit testing with the user
            if(hitTestObject(_root.mcMain)){
                //losing the game
                _root.gameOver = true;
                _root.gotoAndStop('lose');
            }

            if(_root.gameOver){
                removeEventListener(Event.ENTER_FRAME, eFrame);
                this.parent.removeChild(this);
            }
        }
        public function removeListeners():void{
            this.removeEventListener(Event.ENTER_FRAME, eFrame);
        }
    }
}

Answer 1

错误表示您在代码中调用了hitTestObject(null)，这是无效的。

从您分享的代码中，可能是bulletTarget或_root.mcMain。

TypeError：错误＃2007：参数hitTestObject必须为非null

1 个答案: