android判断一个Activity是否处于栈顶的实例

/** 
 * 
 * 判断某activity是否处于栈顶 
 * @return true在栈顶 false不在栈顶 
 */ 
private boolean isActivityTop(Class cls,Context context){ 
 ActivityManager manager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE); 
 String name = manager.getRunningTasks(1).get(0).topActivity.getClassName(); 
 return name.equals(cls.getName()); 
}