android 弹出全局加载等待动画

　　/**
* 弹出loading动画
*/
public static void showLoading(Activity activity) {
View popView = activity.getLayoutInflater().inflate(R.layout.pop_loading_layout, null, false);
//运行动画
((AnimationDrawable) (popView.findViewById(R.id.carAnim)).getBackground()).start();

loading = new PopupWindow(popView,
ViewGroup.LayoutParams.MATCH_PARENT,
ViewGroup.LayoutParams.MATCH_PARENT);
loading.setTouchable(true);
loading.setOutsideTouchable(false);
loading.setBackgroundDrawable(null);
　　　　 //获取Activity的内容页
　　　　 loading.showAtLocation(activity.getWindow().getDecorView().findViewById(android.R.id.content),
Gravity.START | Gravity.TOP, 0, 0);
loading.update();
}