android - 动态 BroadcastReceivers : LocalBroadcastManager. registerReceiver 与 registerReceiver

Question

我正在尝试接收来自具有 2 个不同接收器的服务的广播。一个接收器更新是一个 View ，所以我在 Activity 的 onResume 方法中注册了它。

当应用程序不在前台时，我会使用另一个接收器，以便在后台服务完成时显示系统通知。

下面的代码是我注册接收器的方式:

@Override
protected void onPause() {
    // unregister local
    unregisterReceiver(localReceiver);

    // register remote
    registerReceiver(remoteReceiver, filter);
    super.onPause();
}

@Override
protected void onResume() {
    super.onResume();
    // remove remote receiver
    // since remote is only registered in onPause it won't be registered during the first onResume call
    // so we want to ignore any exceptions
    try {
        unregisterReceiver(remoteReceiver);
    } catch (IllegalArgumentException e) {
        Log.e(LOG_TAG, "No receiver registered, could be first time");
    }

    // add local receiver
    registerReceiver(localReceiver, filter);
    Log.i(LOG_TAG, "resumed. should be registered");
}

两个接收器在 Activity 类的顶部像这样实例化:

BroadcastReceiver localReceiver = new BroadcastReceiver() { ... };

WaitTimeReceiver remoteReceiver = new WaitTimeReceiver();

服务的 Intent 是:

broadcastIntent = new Intent(Support.SERVICE_BR);
broadcastIntent.addCategory(Intent.CATEGORY_DEFAULT);

// later on sends using
sendBroadcast(broadcastIntent);

Activity 中的 Filter 匹配:

filter.addAction(Support.SERVICE_BR);
filter.addCategory(Intent.CATEGORY_DEFAULT);

以上一切正常，暂停恢复功能按预期工作，但我的问题是为什么 LocalBroadcastManager 没有？

使用 LocalBroadcastManager lbm = LocalBroadcastManager.getInstance(this) 然后调用 lbm.registerReceiver(localReceiver) 没有收到我的任何广播。

为什么 LocalBroadcastManager 没有收到我的任何广播？

Answer 1

向 LocalBroadcastManager 注册的

BroadcastReceiver 只能接收由 LocalBroadcastManager 发送的广播。 Activity 或 Service 的 sendBroadcast() 方法发送的广播无法被 LocalBroadcastManager 接收器接收。

改为使用 LocalBroadcastManager#sendBroadcast() 方法。例如:

LocalBroadcastManager.getInstance(this).sendBroadcast(intent)