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copied!<p>I haven't done game development on Android but I have been creating an application that involves a lot of animated and scrolling UI elements. For this project I've used a mixture of normal extended Views and SurfaceViews, and I've had to borrow lots of techniques traditionally used in game programming. Along the way I've learned how normal Views and SurfaceViews differ, and the pros and cons of using each. </p> <p>The big difference between the two, which I think is important to grasp, is that with a SurfaceView you're in effect almost directly writing to the screen buffer (not technically correct - but the easiest way to think about it) as soon as you want, and often as you'd like (within limits). It doesn't 'sit' within the normal View hierarchy. Being able to draw in this manner allows for fast animated graphics (particularly by offsetting bitmaps to create scrolling backgrounds and overlaying animated bitmap sprites over the top). Your code does the drawing directly when it wants to. Main disadvantage of a SurfaceView as far as I have been able to tell from my own experience is that you cannot have any other View appear behind it (i.e. no transparency effects). </p> <p>A normal View on the other hand sits in the normal View hierarchy. Unlike with a SurfaceView you <em>cannot</em> perform a redraw of a normal View as soon as your code wants to. You have to call <code>invalidate()</code> (or <code>postInvalidate()</code> from a non-UI thread) on that View to tell the system that you want to redraw it, and then the system will eventually call that View's <code>onDraw()</code> after some time to do the drawing. There's no guarantee on how quickly that'll be called and this potentially limits the speed at which you can update graphics. The advantage of a normal View however is that it sits within the normal View heirarchy and you can have Views placed on top of each other with transparency and so on. </p>

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