android 获取当前屏幕显示的Activity

<uses-permission android:name=“android.permission.GET_TASKS” />

//判断当前界面显示的是哪个Activity
public static String getTopActivity(Context context){
ActivityManager am = (ActivityManager) context.getSystemService(context.ACTIVITY_SERVICE);
ComponentName cn = am.getRunningTasks(1).get(0).topActivity;
Log.d("Chunna.zheng", "pkg:"+cn.getPackageName());//包名
Log.d("Chunna.zheng", "cls:"+cn.getClassName());//包名加类名
return cn.getClassName();
}