title: Laggy scrolling in UITextView while a CABasicAnimation is running
body: <p>I've implemented a simple animation in my app. I achieve the animation by cross-fading between four image frames using a <code>CABasicAnimation</code> that has a from and to value set to <code>(id)(myimage.CGImage)</code>. The animation is on its own CALayer but while scrolling a pop-up UITextView in its own small subview, the text scrolling is very jerky during a frame blend, and also pauses the animation while scrolling. Would putting the animation in its own thread alleviate the problem or is this simply to do with a complex operation being done by Core Animation?</p>
  
  <p>Thanks for any help!</p>