remove MC after hittest

[florianvanthuyn]

Hi all!

I'm making a little flash game for a school assignment, and I'm pretty much done with the coding, except for one thing:

the hittest and the removing of the MC that got hit by something.

I'll first explain the situation:

The game is for a 7 year old (that was obligated) and it's made in one frame (so far) with in it an animal with a basket (which can be moved to the left and the right with the arrow keys), a background and a fruit MC which contains several frames, each representing a different object.

The fruit is placed through a class Fruit, so I have to call a new Fruit(x,y); to het one on stage.

This is the code which attaches instances to the stage, and tweens them to fall down.

var numFruit:uint = 5;
var speed:uint = 10;

var t:Timer = new Timer(3000, numFruit);
t.addEventListener(TimerEvent.TIMER, tikker);

t.start();

function tikker(event:TimerEvent)
{
// 46 is the width of the fruit MC and 30, its height
var fruit:Fruit = new Fruit((Math.random()*stage.stageWidth - 46),-30);
this.addChild(fruit);

var fTween:Tween = new Tween(fruit,"y",null,fruit.y,stage.stageHeight,speed,true);
}

The object of the game of to catch whatever falls from the sky in the basket.

What I would like to know is:
- how do I start a hittest check for every object (no matter what shape it is) falling from the sky?
- how do I remove that object when a true is returned?

[florianvanthuyn]

Oh, almost forgot ..
The animal is called m and the hitzone is inside of it and is called area.

If you think you know how to fix this or what's definately wrong with my code or if you want to see the class code, please post a reply and I'll get back to you as soon as I can!

[florianvanthuyn]

Since I don't seem to get any response, I'll post some more of the AS I'm using.
I've succeeded in removing them, but when the first one hits the character, I get a stream of errors

This is the error btw:

TypeError: Error #1009: Cannot access a property or method of a null object reference at Fruit/checkHit()

The code which I'm using to make new Fruit objects can be found in my first post, and here's the Fruit class:

package 
{
	import flash.display.MovieClip;
	import flash.events.Event;

	public class Fruit extends MovieClip
	{
		var score:uint = 0;
		
		public function Fruit(xPos:Number, yPos:Number)
		{
			this.x = xPos;
			this.y = yPos;

			gotoAndStop(Math.ceil(Math.random()*3));
			addEventListener(Event.ENTER_FRAME, checkHit);
		}
		
		public function checkHit(e:Event)
		{
			if(this.y > MovieClip(parent).m.y)
			{
				MovieClip(parent).removeChild(this);
			}
		}
	}
}

[Mazoonist]

The reason for all the errors you're getting is that before you remove the object, you must first remove the event listener for the enter frame. So add in this line:
removeEventListener(Event.ENTER_FRAME, checkHit);

Also, in your other code, you must declare the tween variables outside of the function that uses them, or they will get garbage collected, sometimes before they have a chance to complete:

//declare the variable outside of the function:
var fTween:Tween;
//then, in the function:
function tikker(event:TimerEvent) 
{
     //other code
     fTween = new Tween(.... etc);
}

[florianvanthuyn]

Thanks Mazoonist! That cleared out something I actually should have found on my own, since it's something we do almost every day in class, but still .. I always seem to attract those stupid little script errors ..

But thanks again, I'll post my future problems (yes, I'm always very optimistic) here as well, when they arive (and they will! )