如何在android显示之前从android中获取数据

Question

我想在显示给用户 之前检查通知数据JSON对象是否可能？如果有可能如何做到这一点 感谢您的帮助

Answer 1

在fcm服务onMessageReceived其传递到通知

Answer 2

首先分析和解析在FCM服务类获得JSON前检查JSON，然后显示通知按要求。

Answer 3

如果您使用FCM，则可以使用此服务。

public class MyFirebaseMessagingService extends FirebaseMessagingService { 
private static final String TAG = "MyFirebaseMsgService"; 

/** 
* Called when message is received. 
* 
* @param remoteMessage Object representing the message received from Firebase Cloud Messaging. 
*/ 
// [START receive_message] 
@Override 
public void onMessageReceived(RemoteMessage remoteMessage) { 
    // [START_EXCLUDE] 
    // There are two types of messages data messages and notification messages. Data messages are handled 
    // here in onMessageReceived whether the app is in the foreground or background. Data messages are the type 
    // traditionally used with GCM. Notification messages are only received here in onMessageReceived when the app 
    // is in the foreground. When the app is in the background an automatically generated notification is displayed. 
    // When the user taps on the notification they are returned to the app. Messages containing both notification 
    // and data payloads are treated as notification messages. The Firebase console always sends notification 
    // messages. For more see: https://firebase.google.com/docs/cloud-messaging/concept-options 
    // [END_EXCLUDE] 

    // TODO(developer): Handle FCM messages here. 
    Log.d(TAG, "From: " + remoteMessage.getFrom()); 

    // Check if message contains a data payload. 
    if (remoteMessage.getData().size() > 0) { 
     Log.d(TAG, "Message data payload: " + remoteMessage.getData()); 
    } 

    // Check if message contains a notification payload. 
    if (remoteMessage.getNotification() != null) { 
     Log.d(TAG, "Message Notification Body: " + remoteMessage.getNotification().getBody()); 
    } 

    sendNotification("String From Data Payload"); 

    // Also if you intend on generating your own notifications as a result of a received FCM 
    // message, here is where that should be initiated. See sendNotification method below. 
} 

remoteMessage包含由服务接收的消息。收到消息后，您可以使用remoteData.getData()来处理您的data有效载荷，该地址存储为地图。您可以使用remote.getData().get("json_key")来获得data有效载荷内发送的json_key的特定值。

获取数据，你可以使用的方法sendNotification，具体如下：

private void sendNotification(String messageBody) { 
    Intent intent = new Intent(this, MainActivity.class); 
    intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); 
    PendingIntent pendingIntent = PendingIntent.getActivity(this, 0 /* Request code */, intent, 
      PendingIntent.FLAG_ONE_SHOT); 

    Uri defaultSoundUri= RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION); 
    NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this) 
      .setSmallIcon(R.drawable.logo) 
      .setContentTitle("FCM Message") 
      .setContentText(messageBody) 
      .setAutoCancel(true) 
      .setSound(defaultSoundUri) 
      .setContentIntent(pendingIntent); 

    NotificationManager notificationManager = 
      (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE); 

    notificationManager.notify(0 /* ID of notification */, notificationBuilder.build()); 
}