Set limit for b2Body class object moving in coco2d iPhone application

I have one object of b2Body class. But I was it to move just say 25% of the screen from bot开发者_开发知识库tom. But it keeps moving though i set boundries.

Another option was to use setPosition once i reach that condition but in documentation this method exists but while implementation it throws error.

Can anyone please help?

Thank you,

Ankita

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Here's a great tutorial that explains the basics of box2D demonstrated using cocos2d for drawing. It specifically shows how to make physical boundaries for the screen, which i think is a better way of achieving what you want to do than "interfering" with the box2d world by setting positions and forces directly.

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You can just add CCColorLayer and put b2Body into it. It will move for that layer only. You can give x,y, heigh and width for layer.