Frame animation

【Frame animation】

　　An animation defined in XML that shows a sequence of images in order (like a film).

　　　　res/drawable/filename.xml

　　Resource pointer to an AnimationDrawable.

　　　　In Java: R.drawable.filename

　　

　　XML file saved at res/anim/rocket.xml:

　　

　　This application code will set the animation as the background for a View, then play the animation:

ImageView rocketImage = (ImageView) findViewById(R.id.rocket_image);
rocketImage.setBackgroundResource(R.drawable.rocket_thrust);
rocketAnimation = (AnimationDrawable) rocketImage.getBackground();
rocketAnimation.start();

参考：http://android.xsoftlab.net/guide/topics/resources/animation-resource.html#Frame