由网友(笑春风)分享简介：我看Intent.FLAG_ACTIVITY_CLEAR_TOP的行为。I am watching a behavior of Intent.FLAG_ACTIVITY_CLEAR_TOP.例如我有三个活动A，B和C现在流量为A - > B - > C For example i have three a...

我看Intent.FLAG_ACTIVITY_CLEAR_TOP的行为。

I am watching a behavior of Intent.FLAG_ACTIVITY_CLEAR_TOP.

例如我有三个活动 A，B和C 现在流量为A - > B - > C

For example i have three activities A,B and C Now Flow is A -> B -> C

现在，当我开始从C使用此标志与下面code。

Now when i am starting A from C with this flag with following code.

 Intent intent_to_a=new Intent(C.this,A.class);
                intent_to_home.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                startActivity(intent_to_a);

AFAIK，Intent.FLAG_ACTIVITY_CLEAR_TOP应该删除B和应该恢复一个。它也做相同的，但在一个陌生的方式。 它消除了B，比删除比创建A. A的方法的onDestroy也被调用。 谁能告诉我它是正确的还是不？ 如果我不希望它得到破坏我应该怎么办？

AFAIK, Intent.FLAG_ACTIVITY_CLEAR_TOP should remove B and should resume the A .It also does the same but in a strange way. It removes B , than removes A than creates A. Method onDestroy of A is also being called. Can anyone tell me is it proper or not? If i don't want it to get destroy what should i do?

推荐答案

使用FLAG_ACTIVITY_REORDER_TO_FRONT，然后使用一个意图告诉B至完成。

Use FLAG_ACTIVITY_REORDER_TO_FRONT and then use an intent to tell B to finish.

活动B：

private BroadcastReceiver finishReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            finish();
        }
    };
public void onCreate() {
LocalBroadcastManager.getInstance(this)
                .registerReceiver(finishReceiver ,
                        new IntentFilter("B-finish"));
}
public void onDestroy() {
        LocalBroadcastManager.getInstance(this).unregisterReceiver(
                finishReceiver );
}

活动C：

LocalBroadcastManager.getInstance(this).sendBroadcast(
                new Intent("B-finish"));
Intent intent_to_a=new Intent(C.this,A.class);
                intent_to_home.setFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
                startActivity(intent_to_a);