Making a draw/paint app

I'd like to include a simple draw feature on my app. A friend told me I can't use canvas because I need to control the frame buffer and not redraw the entire screen every for every frame. He suggested I find a openGL 2d engine. I've searched around and I've only found Rokon which doesn't have any documentation and the examples aren't quite what I ne开发者_开发百科ed.

Any suggestions?

I don't really understand what the problem is? If you simply wish to redraw some portion of the canvas you can use invalidate(rect).

http://developer.android.com/reference/android/view/View.html#invalidate()

Just create a custom veiw by extending the view class. in this custome view override the onDraw method. Android itself takes care of the pixels that have been changed and calling invalidate only refreshes the pixels that have been marked dirty