iPhone animation: how do I animate the filling up of an area?

Posted by Sandeep on Stack Overflow See other posts from Stack Overflow or by Sandeep
Published on 2010-05-25T14:09:43Z Indexed on 2010/05/25 14:11 UTC
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Filed under:

iphone

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animation

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area

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fill

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keyframe

Consider a circle. Now consider a radius of the circle, drawn from the center of the circle towards the right. Now imagine that the radius is rotating about the center of the circle, sweeping out an area as it rotates. My problem is: I want to use iPhone's animation techniques to fill up the swept out area with a different color from the background area of the circle, as the radius rotates from 0 degrees to any chosen number of degrees about the circle.

I've looked through the Core Animation API, KeyFrame Animations, etc. but I am not able to find out how to do this. Any hints will be most welcome.

Thanks, Sandeep

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