Question

所以我在android中学习了BroadcastReceiver。 BroadcastReceivers基于观察者设计模式（这使得它们非常有趣）所以我想要实现的是广播我的消息，并在同一活动内我希望收到消息（仅用于测试目的）。这是代码段

    Log.d("ABC", "sending");
    Intent intent = new Intent("com.yourcompany.testIntent");
    intent.putExtra("value", "test");
    sendBroadcast(intent);



    Log.d("ABC", "sent");

    IntentFilter filter = new IntentFilter("com.yourcompany.testIntent");
    BroadcastReceiver receiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            Log.d("ABC","INSIDE ");
            String value =  intent.getExtras().getString("value");
        }
    };

    Log.d("ABC", "receiving");
    registerReceiver(receiver, filter);
    Log.d("ABC", "received");

这是调试输出

04-06 20：40：52.446 20149-20149 / com.example.illuminati.broadcastreceiver D / ABC：发送 04-06 20：40：52.447 20149-20149 / com.example.illuminati.broadcastreceiver D / ABC：04-06发送 20：40：52.448 20149-20149 / com.example.illuminati.broadcastreceiver D / ABC：收到04-06 20：40：52.453 20149-20149 / com.example.illuminati.broadcastreceiver D / ABC：收到

为什么它没有进入onReceive（）方法
我在这里失踪了什么有什么帮助吗？

Answer 1

您在注册广播接收器之前发送广播消息。尝试按以下方式进行，它将起作用：

IntentFilter filter = new IntentFilter("com.yourcompany.testIntent");
    BroadcastReceiver receiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            Log.d("ABC", "INSIDE ");
            String value = intent.getExtras().getString("value");
        }
    };
    registerReceiver(receiver, filter);
    Intent intent = new Intent("com.yourcompany.testIntent");
    intent.putExtra("value", "test");
    sendBroadcast(intent);

Answer 2

如果您想在应用内广播消息（而不是每个安装的应用），您还应该考虑使用LocalBroadcastManager。见https://developer.android.com/reference/android/support/v4/content/LocalBroadcastManager.html

无法接收同一活动中的广播

2 个答案: