Masking a Drawable/Bitmap on Android

Posted by Joshua Rodgers on Stack Overflow See other posts from Stack Overflow or by Joshua Rodgers
Published on 2010-04-12T17:08:17Z Indexed on 2010/04/12 17:13 UTC
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android

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bitmap

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drawable

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mask

I'm currently looking for a way to use a black and white bitmap to mask the alpha channel of another bitmap or Drawable on Android. I'm curious as to what the best way to do this is. I certainly have a couple of ideas for how to do this, but they are not optimal.

I need to be able to apply a new mask to the image every so often (the black and white bitmap will change every few seconds).

Any feedback on how to achieve this would be greatly appreciated.

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