如何在 android 中收到来自 firebase 的消息时创建事件侦听器？

Question

我正在使用 firebase 接收消息。收到消息时 (onMessageReceived())。我想检查消息是否包含所需的字符串（比如 "hello"）。如果是，我希望它被另一个片段知道，这样片段中的一些方法将根据消息被调用。

为此，我想在收到消息时创建事件侦听器。在我的片段中，将调用两个 API。 on API 将调用 onCreatedView()。根据来自 firebase 的消息，应该调用第二个 API 。这两个 API 调用应该在几分之一毫秒内完成。

MyFireBaseMessage.java

public class MyMessagingService extends FirebaseMessagingService {

@Override
public void onMessageReceived(RemoteMessage remoteMessage) {
    super.onMessageReceived(remoteMessage);
    Log.d("message here","message here "+ remoteMessage.getData().toString());
    String value = remoteMessage.getData().get("msg");
    Log.d("value here","value here"+" "+value);
    if (value.equalsIgnoreCase("hello"))
    {
        //implement custom event listener here
    }
}
}

Answer 1

如果 hello 是消息格式中的关键字

，请试试这个

if (remoteMessage.getData().containsKey("hello")) {
}

或者如果 hello 是消息字符串，那么试试这个

Map<String, String> params = remoteMessage.getData();
JSONObject fullObject = new JSONObject(params);
String messageString = fullObject.getString("msg");

希望有用！！

Answer 2

我现在能想到的一种方法是使用 LocalBroadcast。这样做

修改您的 Firebase 服务并放入此内容

public class MyMessagingService extends FirebaseMessagingService {
private LocalBroadcastManager broadcaster;

@Override
public void onCreate() {
    broadcaster = LocalBroadcastManager.getInstance(this);
}


@Override
public void onMessageReceived(RemoteMessage remoteMessage) {
    super.onMessageReceived(remoteMessage);
    Log.d("message here", "message here " + remoteMessage.getData().toString());
    String value = remoteMessage.getData().get("msg");
    Log.d("value here", "value here" + " " + value);
    if (value.equalsIgnoreCase("hello")) {
        Intent intent = new Intent("custom-listener");
        broadcaster.sendBroadcast(intent)
    }
}

}

在片段中进行更改class

public class BlankFragment 扩展片段 {

    Context context;
    BroadcastReceiver br;

    public BlankFragment() {
        // Required empty public constructor
    }

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        this.context = context;
    }

    @Override
    public void onResume() {
        super.onResume();
        setup();
    }

    @Override
    public void onDestroyView() {
        super.onDestroyView();
        LocalBroadcastManager.getInstance(context).unregisterReceiver(mMessageReceiver);
    }

    private void setup() {
        LocalBroadcastManager.getInstance(context).registerReceiver(mMessageReceiver,
                new IntentFilter("custom-listener"));
    }


    private BroadcastReceiver mMessageReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            // Get extra data included in the Intent
            String message = intent.getStringExtra("message");
            Log.d("receiver", "Got message: " + message);
        }
    };

}

通过广播，您将能够收听您想要收听的活动。当您的 if 条件为真时，片段 class 中的 onReceive 方法将被触发，即 value.equalsIgnoreCase("hello")

对于此答案的格式，我们深表歉意。难以调整。

Answer 3

为此，请在您的应用中使用本地广播接收器

示例：

在通知屏幕中像这样使用接收器 @Override

public void onMessageReceived(RemoteMessage remoteMessage) 

{
super.onMessageReceived(remoteMessage);
Log.d("message here", "message here " + remoteMessage.getData().toString());
String value = remoteMessage.getData().get("msg");
Log.d("value here", "value here" + " " + value);
if (value.equalsIgnoreCase("hello")) 
{
    Intent intent = new Intent("custom-listener");
    broadcaster.sendBroadcast(intent)
}
}
and in fragment register broadcast receiver in onResume method  like this

 getActivity().registerReceiver(broadcastReceiver, new IntentFilter("custom-listener"));

也在 onPause 方法中取消注册接收器

       getActivity().unregisterReceiver(broadcastReceiver);

并在可以调用 api 的片段中创建广播接收器方法，就像这样

 private BroadcastReceiver broadcastReceiver = new BroadcastReceiver() 
{
    @Override
    public void onReceive(Context context, Intent intent) 


};

如何在 android 中收到来自 firebase 的消息时创建事件侦听器？

How to create event listener when message from firebase received in android?

java

android

firebase

event-listener

eventhandler