[MX04]Unresolved problem with "clip detection" logic

The code below seems absolutely watertight to me, but for the life of me I can’t see why it doesn’t work as intended:

Basically I have a ball that travels across 2 movie clips & should start reversing once it senses it is over clip 2.

I’ll set out the code as it currently appears in the movie & then a commented version that shows my logic with it & possibly where I’m going wrong.

An fla is also attached.

Actual Code:

code:

---

 _root.hold_mc.trackOne_mc.num = 1;

_root.hold_mc.trackTwo_mc.num = 2;

done = 0;

_root.ball_mc.onEnterFrame = function() {

	this._x += 2;

	for (i in _root.hold_mc) {

		if (_root.ball_mc.hitTest(_root.hold_mc[i]) && done == 0) {

			numHit = _root.hold_mc[i].num;

			done = 1;

			trace(_root.hold_mc[i].num);

			if (numHit != _root.hold_mc[i].num) {

				_root.ball_mc.onEnterFrame = null;

				_root.ball_mc.onEnterFrame = function() {

					_root.ball_mc._x -= 2;

				};

			}

		}

	}

}; 

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Commented code:

code:

---

// I have assigned variables to each of the clips that the ball travels over so as to //differentiate them:                                                 

_root.hold_mc.trackOne_mc.num = 1 

_root.hold_mc.trackTwo_mc.num = 2;



done = 0;// A flag variable to get the .num value of the first clip



// An onEnterFrame function to move the ball



_root.ball_mc.onEnterFrame = function() {

	this._x += 2;



// A for(in) loop to capture the .num value of the first clip to then check against it.

	

for (i in _root.hold_mc) {

		if (_root.ball_mc.hitTest(_root.hold_mc[i]) && done == 0) {

			numHit = _root.hold_mc[i].num;

			done = 1;



/*Ok this is where I think it is breaking down. To my mind this section will check the ball as it moves along – if whatever number “_root.hold_mc[i].num” throws up is different to the “numHit” variable designated above the ball goes into reverse*/

 			

			if (numHit != _root.hold_mc[i].num) {

				_root.ball_mc.onEnterFrame = null;

				_root.ball_mc.onEnterFrame = function() {

					_root.ball_mc._x -= 2;

				};

			}

		}

	}

};

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