android源码关于加载anim的xml文件的描述

private static Animation createAnimationFromXml(Context c, XmlPullParser parser,
AnimationSet parent, AttributeSet attrs) throws XmlPullParserException, IOException {

Animation anim = null;

// Make sure we are on a start tag.
int type;
int depth = parser.getDepth();

while (((type=parser.next()) != XmlPullParser.END_TAG || parser.getDepth() > depth)
&& type != XmlPullParser.END_DOCUMENT) {

if (type != XmlPullParser.START_TAG) {
continue;
}

String  name = parser.getName();

if (name.equals("set")) {
anim = new AnimationSet(c, attrs);
createAnimationFromXml(c, parser, (AnimationSet)anim, attrs);
} else if (name.equals("alpha")) {
anim = new AlphaAnimation(c, attrs);
} else if (name.equals("scale")) {
anim = new ScaleAnimation(c, attrs);
}  else if (name.equals("rotate")) {
anim = new RotateAnimation(c, attrs);
}  else if (name.equals("translate")) {
anim = new TranslateAnimation(c, attrs);
} else {
throw new RuntimeException("Unknown animation name: " + parser.getName());
}

if (parent != null) {
parent.addAnimation(anim);
}
}

return anim;

}