[android] How to handle notification when app in background in Firebase

Here is my manifest

    <service android:name=".fcm.PshycoFirebaseMessagingServices">
        <intent-filter>
            <action android:name="com.google.firebase.MESSAGING_EVENT" />
        </intent-filter>
    </service>

    <service android:name=".fcm.PshycoFirebaseInstanceIDService">
        <intent-filter>
            <action android:name="com.google.firebase.INSTANCE_ID_EVENT" />
        </intent-filter>
    </service>

When the app is in background and notification arrives then the default notification comes and doesn't run my code of onMessageReceived.

Here is my onMessageReceived code. This invokes if my app is running on foreground, not when app in background. How to run this code when the app is in background too?

// [START receive_message]
@Override
public void onMessageReceived(RemoteMessage remoteMessage) {
    // TODO(developer): Handle FCM messages here.
    // If the application is in the foreground handle both data and notification messages here.
    // 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.
    data = remoteMessage.getData();
    String title = remoteMessage.getNotification().getTitle();
    String message = remoteMessage.getNotification().getBody();
    String imageUrl = (String) data.get("image");
    String action = (String) data.get("action");
    Log.i(TAG, "onMessageReceived: title : "+title);
    Log.i(TAG, "onMessageReceived: message : "+message);
    Log.i(TAG, "onMessageReceived: imageUrl : "+imageUrl);
    Log.i(TAG, "onMessageReceived: action : "+action);

    if (imageUrl == null) {
        sendNotification(title,message,action);
    } else {
        new BigPictureNotification(this,title,message,imageUrl,action);
    }
}
// [END receive_message]

Since 2019, Google Firebase has a big change in their APIs I mean: 'com.google.firebase:firebase-messaging:18.0.0'

in 18.0.0 they removed MyFirebaseInstanceIDService and you need to get token in MyFirebaseMessagingService so you just need to write :

@Override
public void onNewToken(String token) {
    Log.d(TAG, "Refreshed token: " + token);

}

and also in your AndroidManifest.xml, you have to remove :

<service android:name=".service.MyFirebaseInstanceIDService">
        <intent-filter>
            <action android:name="com.google.firebase.INSTANCE_ID_EVENT" />
        </intent-filter>
    </service>

Also, you're recommended to set default values to customize the appearance of notifications. You can specify a custom default icon and a custom default color that are applied whenever equivalent values are not set in the notification payload.

Add these lines inside the application tag to set the custom default icon and custom color:

    <meta-data
        android:name="com.google.firebase.messaging.default_notification_icon"
        android:resource="@drawable/ic_notification" />

    <meta-data
        android:name="com.google.firebase.messaging.default_notification_color"
        android:resource="@color/colorAccent" />

    <meta-data
        android:name="com.google.firebase.messaging.default_notification_channel_id"
        android:value="@string/push_channel" />

now to handle notification messages in a backgrounded app you should define an Intent in your first Activity even if it is SplashScreen, When your app is in the background, Android directs notification messages to the system tray. A user tap on the notification opens the app launcher by default.

for example, if your Json is like this:

 "data": {
"message": "2",
"title": "1",
"pushType" : "banner",
"bannerLink": "http://www.google.com",
"image" : "https://www.google.com/images/branding/googlelogo/1x/googlelogo_color_272x92dp.png"}

you just need to write a simple intent to get those values:

        Bundle extras = intent.getExtras();
        String bannerLink = extras.getString("bannerLink");
        ...
        String channelId = extras.getString("channelId");

I figured out the scenarios,

When app is in foreground, onMessageReceived() method is called from the FirebaseService.So the pendingIntent defined in the service class will be called.

And when app is in background, first activity is called.

Now, if you use a splash activity, then must keep in mind the splashactivity will be called, else if there is no splashActivity, then whatever the first activity is, will be called.

Then you need to check getIntent() of the firstActivity to see if it has any bundle .if everything is alright you will see bundle is there with values filled in. If the value in data tag sent from server looks like this,

"data": {
    "user_name": "arefin sajib",
    "value": "user name notification"
  }

Then in the first activity, you will see, there is a valid intent( getIntent() is not null) , valid bundle and inside bundle , there will the whole JSON mentioned above with data as key.

For this scenario, code for extraction of value will look like this,

    if(getIntent()!=null){
            Bundle bundle = getIntent().getExtras();
            if (bundle != null) {
                try {
                   JSONObject object = new JSONObject(bundle.getStringExtra("data"));
String user_name = object.optString("user_name");

                } catch (JSONException e) {
                    e.printStackTrace();
                }


            }
        }

@Override
public void onMessageReceived(RemoteMessage remoteMessage) {

}

is not called every time it is called only when app is in forground

there is one override method this method is called every time , no matter what app is in foreground or in background or killed but this method is available with this firebase api version

this is the version u have to import from gradle

compile 'com.google.firebase:firebase-messaging:10.2.1'

this is the method

@Override
public void handleIntent(Intent intent) {
    super.handleIntent(intent);

    // you can get ur data here 
    //intent.getExtras().get("your_data_key") 


}

with previous firebase api this method was not there so in that case fire base handle itself when app is in background .... now u have this method what ever u want to do ... u can do it here in this method .....

if you are using previous version than default activity will start in that case u can get data same way

if(getIntent().getExtras() != null && getIntent().getExtras().get("your_data_key") != null) {
String strNotificaiton = getIntent().getExtras().get("your_data_key").toString();

// do what ever u want .... }

generally this is the structure from server we get in notification

{
    "notification": {
        "body": "Cool offers. Get them before expiring!",
        "title": "Flat 80% discount",
        "icon": "appicon",
        "click_action": "activity name" //optional if required.....
    },
    "data": {
        "product_id": 11,
        "product_details": "details.....",
        "other_info": "......."
    }
}

it's up to u how u want to give that data key or u want give notification anything u can give ....... what ever u will give here with same key u will get that data .........

there are few cases if u r not sending click action in that case when u will click on notification default activity will open , but if u want to open your specific activity when app is in background u can call your activity from this on handleIntent method because this is called every time

To capture the message in background you need to use a BroadcastReceiver

import android.content.Context
import android.content.Intent
import android.util.Log
import androidx.legacy.content.WakefulBroadcastReceiver
import com.google.firebase.messaging.RemoteMessage

class FirebaseBroadcastReceiver : WakefulBroadcastReceiver() {

    val TAG: String = FirebaseBroadcastReceiver::class.java.simpleName

    override fun onReceive(context: Context, intent: Intent) {

        val dataBundle = intent.extras
        if (dataBundle != null)
            for (key in dataBundle.keySet()) {
                Log.d(TAG, "dataBundle: " + key + " : " + dataBundle.get(key))
            }
        val remoteMessage = RemoteMessage(dataBundle)
        }
    }

and add this to your manifest:

<receiver
      android:name="MY_PACKAGE_NAME.FirebaseBroadcastReceiver"
      android:exported="true"
      android:permission="com.google.android.c2dm.permission.SEND">
        <intent-filter>
            <action android:name="com.google.android.c2dm.intent.RECEIVE" />
        </intent-filter>
</receiver>

Since the display-messages which are sent from Firebase Notification UI only works if your app is in foreground. For data-messages, there is a need to make a POST call to FCM

Steps

1. Install Advanced Rest Client Google Chrome Extension

2. Add the following headers

   Key: Content-Type, Value: application/json

   Key: Authorization, Value: key="your server key"

3. Add the body

   • If using topics :

     {
         "to" : "/topics/topic_name",
         "data": {
         "key1" : "value1",
         "key2" : "value2",
         }
     }
     

   • If using registration id :

     {
         "registration_ids" : "[{"id"},{id1}]",
         "data": {
         "key1" : "value1",
         "key2" : "value2",
          }
     }
     

Thats it!. Now listen to onMessageReceived callback as usual.

@Override
public void onMessageReceived(RemoteMessage remoteMessage) { 
     Map<String, String> data = remoteMessage.getData();
     String value1 = data.get("key1");
     String value2 = data.get("key2");
}

Simple summary like this

• if your app is running;

  onMessageReceived()
  

is triggers.

• if your app is not running (killed by swiping) ;

  onMessageReceived()
  

is not triggered and delivered by direclty. If you have any specialy key-value pair. They don' t work beacuse of onMessageReceived() not working.

I' ve found this way;

In your launcher activity, put this logic,

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState, R.layout.activity_splash);

    if (getIntent().getExtras() != null && getIntent().getExtras().containsKey("PACKAGE_NAME")) {

        // do what you want

        // and this for killing app if we dont want to start
        android.os.Process.killProcess(android.os.Process.myPid());

    } else {

        //continue to app
    }
}

in this if block, search for your keys according to firebase UI.

In this example my key and value like above; (sorry for language =))

When my code works, i get "com.rda.note".

android.os.Process.killProcess(android.os.Process.myPid());

with this line of code, i closed my application and open Google Play Market

happy coding =)

June 2018 Answer -

You have to make sure there is not a "notification" keyword anywhere in the message. Only include "data", and the app will be able to handle the message in onMessageReceived, even if in background or killed.

Using Cloud Functions:

const message = {
    token: token_id,   // obtain device token id by querying data in firebase
    data: {
       title: "my_custom_title",
       body:  "my_custom_body_message"
       }
    }


return admin.messaging().send(message).then(response => {
    // handle response
});

Then in your onMessageReceived(), in your class extending com.google.firebase.messaging.FirebaseMessagingService :

if (data != null) {
  Log.d(TAG, "data title is: " + data.get("title");
  Log.d(TAG, "data body is: " + data.get("body");
}

// build notification using the body, title, and whatever else you want.

According to OAUTH 2.0:

There will be Auth problem for this case beacuse FCM now using OAUTH 2

So I read firebase documentation and according to documentation new way to post data message is;

POST: https://fcm.googleapis.com/v1/projects/YOUR_FIREBASEDB_ID/messages:send

Headers

Key: Content-Type, Value: application/json

Auth

Bearer YOUR_TOKEN 

Example Body

{
   "message":{
    "topic" : "xxx",
    "data" : {
         "body" : "This is a Firebase Cloud Messaging Topic Message!",
         "title" : "FCM Message"
          }
      }
 }

In the url there is Database Id which you can find it on your firebase console. (Go project setttings)

And now lets take our token (It will valid only 1 hr):

First in the Firebase console, open Settings > Service Accounts. Click Generate New Private Key, securely store the JSON file containing the key. I was need this JSON file to authorize server requests manually. I downloaded it.

Then I create a node.js project and used this function to get my token;

var PROJECT_ID = 'YOUR_PROJECT_ID';
var HOST = 'fcm.googleapis.com';
var PATH = '/v1/projects/' + PROJECT_ID + '/messages:send';
var MESSAGING_SCOPE = 'https://www.googleapis.com/auth/firebase.messaging';
var SCOPES = [MESSAGING_SCOPE];

  router.get('/', function(req, res, next) {
      res.render('index', { title: 'Express' });
      getAccessToken().then(function(accessToken) {
        console.log("TOKEN: "+accessToken)
      })

    });

function getAccessToken() {
return new Promise(function(resolve, reject) {
    var key = require('./YOUR_DOWNLOADED_JSON_FILE.json');
    var jwtClient = new google.auth.JWT(
        key.client_email,
        null,
        key.private_key,
        SCOPES,
        null
    );
    jwtClient.authorize(function(err, tokens) {
        if (err) {
            reject(err);
            return;
        }
        resolve(tokens.access_token);
    });
});
}

Now I can use this token in my post request. Then I post my data message, and it is now handled by my apps onMessageReceived function.

you want to work onMessageReceived(RemoteMessage remoteMessage) in background send only data part notification part this:

"data":    "image": "",    "message": "Firebase Push Message Using API", 

"AnotherActivity": "True", "to" : "device id Or Device token"

By this onMessageRecivied is call background and foreground no need to handle notification using notification tray on your launcher activity. Handle data payload in using this:

  public void onMessageReceived(RemoteMessage remoteMessage)
    if (remoteMessage.getData().size() > 0) 
    Log.d(TAG, "Message data payload: " + remoteMessage.getData());      

2017 updated answer

Here is a clear-cut answer from the docs regarding this:

According to the firebase documentation in send downstream using firebase, there is 2 type of payload :

1. data

   This parameter specifies the custom key-value pairs of the message's payload. Client app is responsible for processing data messages. Data messages have only custom key-value pairs.

2. notification

   This parameter specifies the predefined, user-visible key-value pairs of the notification payload. FCM automatically displays the message to end-user devices on behalf of the client app. Notification messages have a predefined set of user-visible keys.

When you are in the foreground you can get the data inside FCM using onMessageReceived(), you can get your data from data payload.

data = remoteMessage.getData();
String customData = (String) data.get("customData");

When you are in background, FCM will showing notification in system tray based on the info from notification payload. Title, message, and icon which used for the notification on system tray are get from the notification payload.

{
  "notification": {
        "title" : "title",
        "body"  : "body text",
        "icon"  : "ic_notification",
        "click_action" : "OPEN_ACTIVITY_1"
       }
}

This notification payload are used when you want to automactically showing notification on the system tray when your app is in the background. To get notification data when your app in the background, you should add click_action inside notification payload.

If you want to open your app and perform a specific action [while backgrounded], set click_action in the notification payload and map it to an intent filter in the Activity you want to launch. For example, set click_action to OPEN_ACTIVITY_1 to trigger an intent filter like the following:

<intent-filter>
  <action android:name="OPEN_ACTIVITY_1" />
  <category android:name="android.intent.category.DEFAULT" />
</intent-filter>

Put that intent-filter on your manifest, inside one of your activity tag. When you click the notification, it will open the app and go straight to activity that you define in click_action, in this case "OPEN_ACTIVTY_1". And inside that activity you can get the data by :

Bundle b = getIntent().getExtras();
String someData = b.getString("someData");

I'm using FCM for my android app and use both of the payload. Here is the example JSON i'm using :

{
  "to": "FCM registration ID",
  "notification": {
    "title" : "title",
    "body"  : "body text",
    "icon"  : "ic_notification",
    "click_action" : "OPEN_ACTIVITY_1"
   },
   "data": {
     "someData"  : "This is some data",
     "someData2" : "etc"
   }
}

According to the docs: May 17, 2017

When your app is in the background, Android directs notification messages to the system tray. A user tap on the notification opens the app launcher by default.

This includes messages that contain both notification and data payload (and all messages sent from the Notifications console). In these cases, the notification is delivered to the device's system tray, and the data payload is delivered in the extras of the intent of your launcher Activity.

So,you should use both of the payload notification + data:

{
  "to": "FCM registration ID",
  "notification": {
    "title" : "title",
    "body"  : "body text",
    "icon"  : "ic_notification"
   },
   "data": {
     "someData"  : "This is some data",
     "someData2" : "etc"
   }
}

There is no need to use click_action.You should just get exras from intent on LAUNCHER activity

<activity android:name=".MainActivity">
        <intent-filter>
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
</activity>

Java code should be on onCreate method on MainActivity :

Intent intent = getIntent();
if (intent != null && intent.getExtras() != null) {
    Bundle extras = intent.getExtras();
    String someData= extras.getString("someData");
    String someData2 = extras.getString("someData2");
}

You can test both of the payload notification + data from Firebase Notifications Console . Don't forget to fill custom data fields on Advanced options section

I feel like all the responses are incomplete but all of them have something that you need to process a notification that have data when your app is in background.

Follow these steps and you will be able to process your notifications when your app is in background.

1.Add an intent-filter like this:

<activity android:name=".MainActivity">
      <intent-filter>
           <action android:name=".MainActivity" />
           <category android:name="android.intent.category.DEFAULT" />
      </intent-filter>
</activity>

to an activity that you want to process the notification data.

2. Send notifications with the next format:

   { 
    "notification" : {
           "click_action" : ".MainActivity", 
           "body" : "new Symulti update !", 
           "title" : "new Symulti update !", 
           "icon" : "ic_notif_symulti" }, 
    "data": { ... },
    "to" : "c9Vaa3ReGdk:APA91bH-AuXgg3lDN2WMcBrNhJZoFtYF9" }
   

The key here is add

"click_action" : ".MainActivity"

where .MainActivity is the activity with the intent-filter that you added in step 1.

3. Get "data" info from notification in the onCreate of ".MainActivity":

   protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_main);
       //get notification data info
       Bundle bundle = getIntent().getExtras();
       if (bundle != null) {
          //bundle must contain all info sent in "data" field of the notification
       }
   }
   

And that should be all you need to do. I hope this helps somebody :)

The easy way to send messages even if the app is in background and foreground as follow:- To send a message using API, you can use a tool called AdvancedREST Client, its a chrome extension, and send a message with the following parameters.

Rest client tool Link: https://chrome.google.com/webstore/detail/advanced-rest-client/hgmloofddffdnphfgcellkdfbfbjeloo

use this url:- https://fcm.googleapis.com/fcm/send Content-Type:application/json Authorization:key=Your Server key From or Authoization key(see below ref)

{ "data": {
    "image": "https://static.pexels.com/photos/4825/red-love-romantic-flowers.jpg",
    "message": "Firebase Push Message Using API"
    "AnotherActivity": "True"
     },
  "to" : "device id Or Device token"
}

Authorization key can be obtained by visiting Google developers console and click on Credentials button on the left menu for your project. Among the API keys listed, the server key will be your authorization key.

And you need to put tokenID of the receiver in the “to” section of your POST request sent using API.

Working as of July 2019

Android compileSdkVersion 28, buildToolsVersion 28.0.3 and firebase-messaging:19.0.1

After many many hours of researching through all of the other StackOverflow questions and answers, and trying innumerable outdated solutions, this solution managed to show notifications in these 3 scenarios:

- App is in foreground:
the notification is received by the onMessageReceived method at my MyFirebaseMessagingService class

- App has been killed (it is not running in background): the notification is sent to the notification tray automatically by FCM. When the user touches the notification the app is launched by calling the activity that has android.intent.category.LAUNCHER in the manifest. You can get the data part of the notification by using getIntent().getExtras() at the onCreate() method.

- App is in background: the notification is sent to the notification tray automatically by FCM. When the user touches the notification the app is brought to the foreground by launching the activity that has android.intent.category.LAUNCHER in the manifest. As my app has launchMode="singleTop" in that activity, the onCreate() method is not called because one activity of the same class is already created, instead the onNewIntent() method of that class is called and you get the data part of the notification there by using intent.getExtras().

Steps: 1- If you define your app's main activity like this:

<activity
    android:name=".MainActivity"
    android:label="@string/app_name"
    android:largeHeap="true"
    android:screenOrientation="portrait"
    android:launchMode="singleTop">
    <intent-filter>
        <action android:name=".MainActivity" />
        <action android:name="android.intent.action.MAIN" />
        <category android:name="android.intent.category.LAUNCHER" />
        <category android:name="android.intent.category.DEFAULT" />
    </intent-filter>
</activity>

2- add these lines at the onCreate() method of your MainActivity.class

Intent i = getIntent();
Bundle extras = i.getExtras();
if (extras != null) {
    for (String key : extras.keySet()) {
        Object value = extras.get(key);
        Log.d(Application.APPTAG, "Extras received at onCreate:  Key: " + key + " Value: " + value);
    }
    String title = extras.getString("title");
    String message = extras.getString("body");
    if (message!=null && message.length()>0) {
        getIntent().removeExtra("body");
        showNotificationInADialog(title, message);
    }
}

and these methods to the same MainActivity.class:

@Override
public void onNewIntent(Intent intent){
    //called when a new intent for this class is created.
    // The main case is when the app was in background, a notification arrives to the tray, and the user touches the notification

    super.onNewIntent(intent);

    Log.d(Application.APPTAG, "onNewIntent - starting");
    Bundle extras = intent.getExtras();
    if (extras != null) {
        for (String key : extras.keySet()) {
            Object value = extras.get(key);
            Log.d(Application.APPTAG, "Extras received at onNewIntent:  Key: " + key + " Value: " + value);
        }
        String title = extras.getString("title");
        String message = extras.getString("body");
        if (message!=null && message.length()>0) {
            getIntent().removeExtra("body");
            showNotificationInADialog(title, message);
        }
    }
}


private void showNotificationInADialog(String title, String message) {

    // show a dialog with the provided title and message
    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setTitle(title);
    builder.setMessage(message);
    builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int whichButton) {
            dialog.cancel();
        }
    });
    AlertDialog alert = builder.create();
    alert.show();
}

3- create the class MyFirebase like this:

package com.yourcompany.app;

import android.content.Intent;
import android.util.Log;

import com.google.firebase.messaging.FirebaseMessagingService;
import com.google.firebase.messaging.RemoteMessage;

public class MyFirebaseMessagingService extends FirebaseMessagingService {


    public MyFirebaseMessagingService() {
        super();
    }

    @Override
    public void onMessageReceived(RemoteMessage remoteMessage) {

        Log.d(Application.APPTAG, "myFirebaseMessagingService - onMessageReceived - message: " + remoteMessage);

        Intent dialogIntent = new Intent(this, NotificationActivity.class);
        dialogIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        dialogIntent.putExtra("msg", remoteMessage);
        startActivity(dialogIntent);

    }

}

4- create a new class NotificationActivity.class like this:

package com.yourcompany.app;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.os.Bundle;
import android.util.Log;

import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.view.ContextThemeWrapper;

import com.google.firebase.messaging.RemoteMessage;

public class NotificationActivity extends AppCompatActivity {

private Activity context;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    context = this;
    Bundle extras = getIntent().getExtras();

    Log.d(Application.APPTAG, "NotificationActivity - onCreate - extras: " + extras);

    if (extras == null) {
        context.finish();
        return;
    }

    RemoteMessage msg = (RemoteMessage) extras.get("msg");

    if (msg == null) {
        context.finish();
        return;
    }

    RemoteMessage.Notification notification = msg.getNotification();

    if (notification == null) {
        context.finish();
        return;
    }

    String dialogMessage;
    try {
        dialogMessage = notification.getBody();
    } catch (Exception e){
        context.finish();
        return;
    }
    String dialogTitle = notification.getTitle();
    if (dialogTitle == null || dialogTitle.length() == 0) {
        dialogTitle = "";
    }

    AlertDialog.Builder builder = new AlertDialog.Builder(new ContextThemeWrapper(context, R.style.myDialog));
    builder.setTitle(dialogTitle);
    builder.setMessage(dialogMessage);
    builder.setPositiveButton(getResources().getString(R.string.accept), new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int whichButton) {
            dialog.cancel();
        }
    });
    AlertDialog alert = builder.create();
    alert.show();

}

}

5- Add these lines to your app Manifest, inside your tags

    <service
        android:name=".MyFirebaseMessagingService"
        android:exported="false">
        <intent-filter>
            <action android:name="com.google.firebase.MESSAGING_EVENT" />
        </intent-filter>
    </service>

    <meta-data android:name="com.google.firebase.messaging.default_notification_channel_id" android:value="@string/default_notification_channel_id"/>

    <activity android:name=".NotificationActivity"
        android:theme="@style/myDialog"> </activity>

    <meta-data
        android:name="com.google.firebase.messaging.default_notification_icon"
        android:resource="@drawable/notification_icon"/>

    <meta-data
        android:name="com.google.firebase.messaging.default_notification_color"
        android:resource="@color/color_accent" />

6- add these lines in your Application.java onCreate() method, or in MainActivity.class onCreate() method:

      // notifications channel creation
  if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
      // Create channel to show notifications.
      String channelId = getResources().getString("default_channel_id");
      String channelName = getResources().getString("General announcements");
      NotificationManager notificationManager = getSystemService(NotificationManager.class);
      notificationManager.createNotificationChannel(new NotificationChannel(channelId,
              channelName, NotificationManager.IMPORTANCE_LOW));
  }

Done.

Now for this to work well in the 3 mentioned scenarios, you have to send the notification from the Firebase web console in the following way:

In the Notification section: Notification Title = Title to display in the notification dialog (optional) Notification text = Message to show to the user (required) Then in the Target section: App = your Android app and in Additional Options section: Android Notification Channel = default_channel_id Custom Data key: title value: (same text here than in the Title field of the Notification section) key: body value: (same text here than in the Message field of the Notification section) key:click_action value: .MainActivity Sound=Disabled
Expires=4 weeks

You can debug it in the Emulator with API 28 with Google Play.

Happy coding!

In general

There are two types of messages in FCM (Firebase Cloud Messaging):

• Display Messages: These messages trigger the onMessageReceived() callback only when your app is in foreground

• Data Messages: Theses messages trigger the onMessageReceived() callback even if your app is in foreground/background/killed

Data Messages example:

{ 
  "to": "/path", 
  "data": 
     { 
      "my_custom_key": "my_custom_value", 
      "my_custom_key2": true 
     } 
}

Display Messages example:

 {
     "notification": {
            "title" : "title",
            "body"  : "body text",
            "icon"  : "ic_notification",
            "click_action" : "OPEN_ACTIVITY_1"
        }
   }

Android side can handle notifications like:

public class MyFirebaseMessagingService extends FirebaseMessagingService {
    …

      @Override public void onMessageReceived(RemoteMessage remoteMessage){
           Map<String, String> data = remoteMessage.getData();
           String myCustomKey = data.get("my_custom_key");
        
       } 

    …

}

More details about FCM you can find here : Set up a Firebase Cloud Messaging client app on Android

Using this code you can get the notification in background/foreground and also put action:

//Data should come in this format from the notification
{
  "to": "/xyz/Notifications",
  "data": {
      "key1": "title notification",
      "key2": "description notification"
  }
}

In-App use this code:

  @Override
    public void onMessageReceived(RemoteMessage remoteMessage) {
        super.onMessageReceived(remoteMessage);
      String key1Data = remoteMessage.getData().get("key1");
      // use key1Data to according to your need
    }

In addition to above answers, If you are testing push notifications using FCM console, 'data' key and object is not added to Push Notification bundle. So you will not receive detailed push notification when App is background or killed.

In this case you have to opt for your back end admin console to test App background scenario.

Here, you will have added 'data' key to your push bundle. so, detailed push will be shown as expected. Hope this helps few.

I've experienced the same problem and recompiled the firebase library and prevented it from sending notifications when the application is in the background

*library https://github.com/erdalceylan/com-google-firebase-messaging

 dependencies {
        compile 'com.google.firebase:firebase-core:11.2.0'
        compile 'com.github.erdalceylan:com-google-firebase-messaging:v1-11.2.0'
    }

*

@WorkerThread
public void onMessageReceived(RemoteMessage var1) {
  //your app is in background or foreground all time calling
}

hope helps. Good luck

Remove notification payload completely from your server request. Send only data and handle it in onMessageReceived(), otherwise your onMessageReceived will not be triggered when the app is in background or killed.

Here is what I am sending from server:

{
  "data":{
    "id": 1,
    "missedRequests": 5
    "addAnyDataHere": 123
  },
  "to": "fhiT7evmZk8:APA91bFJq7Tkly4BtLRXdYvqHno2vHCRkzpJT8QZy0TlIGs......"
}

So you can receive your data in onMessageReceived(RemoteMessage message) like this: (let's say I have to get the id)

Object obj = message.getData().get("id");
        if (obj != null) {
            int id = Integer.valueOf(obj.toString());
        }

And similarly you can get any data which you have sent from server within onMessageReceived().

Thanks to All of you for your Answers. But I solved this by sending data message instead of sending Notification. Server code

<?php
$url = "https://fcm.googleapis.com/fcm/send";
$token = "C-l6T_a7HouUK****";
$serverKey = "AAAAaOcKS00:********";
define( 'API_ACCESS_KEY', $serverKey );
$registrationIds = array($token);
// prep the bundle

$msg = array

(
 'message'  => 'here is a message. message',
 'title'        => 'This is a title. title',
 'subtitle' => 'This is a subtitle. subtitle',
 'tickerText'   => 'Ticker text here...Ticker text here...Ticker text 
 here',
 'vibrate'  => 1,
 'sound'        => 1,
 'largeIcon'    => 'large_icon',
 'smallIcon'    => 'small_icon'

);

$fields = array

(
  'registration_ids'    => $registrationIds,
  'data'            => $msg

);
$headers = array

(
  'Authorization: key=' . API_ACCESS_KEY,
 'Content-Type: application/json'

);


$ch = curl_init();

curl_setopt( $ch,CURLOPT_URL, 'https://android.googleapis.com/gcm/send' 
);

curl_setopt( $ch,CURLOPT_POST, true );

curl_setopt( $ch,CURLOPT_HTTPHEADER, $headers );

curl_setopt( $ch,CURLOPT_RETURNTRANSFER, true );

curl_setopt( $ch,CURLOPT_SSL_VERIFYPEER, false );

curl_setopt( $ch,CURLOPT_POSTFIELDS, json_encode( $fields ) );

$result = curl_exec($ch );

curl_close( $ch );

echo $result;

?>

And caught the Data in onMessageReceived

public class MyFirebaseMessagingService extends FirebaseMessagingService     {

  private static final String TAG = "MyFirebaseMsgService";

@Override
public void onMessageReceived(RemoteMessage remoteMessage) {
    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());

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


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

    String channelId = "idddd";
    Uri defaultSoundUri= RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
    NotificationCompat.Builder notificationBuilder =
            new NotificationCompat.Builder(MyFirebaseMessagingService.this)
                    .setSmallIcon(R.mipmap.ic_launcher)
                    .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());
}
}

Here is more clear concepts about firebase message. I found it from their support team.

Firebase has three message types:

Notification messages : Notification message works on background or foreground. When app is in background, Notification messages are delivered to the system tray. If the app is in the foreground, messages are handled by onMessageReceived() or didReceiveRemoteNotification callbacks. These are essentially what is referred to as Display messages.

Data messages: On Android platform, data message can work on background and foreground. The data message will be handled by onMessageReceived(). A platform specific note here would be: On Android, the data payload can be retrieved in the Intent used to launch your activity. To elaborate, if you have "click_action":"launch_Activity_1", you can retrieve this intent through getIntent() from only Activity_1.

Messages with both notification and data payloads: When in the background, apps receive the notification payload in the notification tray, and only handle the data payload when the user taps on the notification. When in the foreground, your app receives a message object with both payloads available. Secondly, the click_action parameter is often used in notification payload and not in data payload. If used inside data payload, this parameter would be treated as custom key-value pair and therefore you would need to implement custom logic for it to work as intended.

Also, I recommend you to use onMessageReceived method (see Data message) to extract the data bundle. From your logic, I checked the bundle object and haven't found expected data content. Here is a reference to a similar case which might provide more clarity.

For more info visit my this thread

To make firebase library to call your onMessageReceived() in the following cases

1. App in foreground
2. App in background
3. App has been killed

you must not put JSON key 'notification' in your request to firebase API but instead use 'data', see below.

The following message will not call your onMessageReceived() when your app is in the background or killed, and you can't customize your notification.

{
   "to": "/topics/journal",
   "notification": {
       "title" : "title",
       "text": "data!",
       "icon": "ic_notification"
    }
}

but instead using this will work

{
  "to": "/topics/dev_journal",
   "data": {
       "text":"text",
       "title":"",
       "line1":"Journal",
       "line2":"??"
   }
} 

Basically, the message is sent in the argument RemoteMessage along with your data object as Map<String, String>, then you can manage the notification in onMessageReceived as in the snippet here

@Override
public void onMessageReceived(RemoteMessage remoteMessage) { 
     Map<String, String> data = remoteMessage.getData();

     //you can get your text message here.
     String text= data.get("text");


     NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this)
        // optional, this is to make beautiful icon
             .setLargeIcon(BitmapFactory.decodeResource(
                                    getResources(), R.mipmap.ic_launcher))  
        .setSmallIcon(smallIcon)  //mandatory
      .......
    /*You can read more on notification here:
    https://developer.android.com/training/notify-user/build-notification.html
    https://www.youtube.com/watch?v=-iog_fmm6mE
    */
}

According to docs

Handle messages in a backgrounded app

When your app is in the background, Android directs notification messages to the system tray. A user tap on the notification opens the app launcher by default.

This includes messages that contain both notification and data payload. In these cases, the notification is delivered to the device's system tray, and the data payload is delivered in the extras of the intent of your launcher Activity.

If you want to open your app and perform a specific action, set click_action in the notification payload and map it to an intent filter in the Activity you want to launch. For example, set click_action to OPEN_ACTIVITY_1 to trigger an intent filter like the following:

 <intent-filter>   <action android:name="OPEN_ACTIVITY_1" />  
 <category android:name="android.intent.category.DEFAULT" />
 </intent-filter>

Edit :

Based on this thread :

You can't set click_action payload using Firebase Console. You could try testing with a curl command or a custom http server

curl --header "Authorization: key=<YOUR_KEY_GOES_HERE>" 
     --header Content-Type:"application/json" https://fcm.googleapis.com/fcm/send  
     -d "{\"to\":\"/topics/news\",\"notification\": 
         {\"title\": \"Click Action Message\",\"text\": \"Sample message\",
            \"click_action\":\"OPEN_ACTIVITY_1\"}}"

I had same problem. After some digging why my MainActivity is called with intent without data I realized that my LAUNCHER activity (as in Manifest) is SplashActivity. There I found the message data and forwarded them to MainActivity. Works like sharm. I beleive this can help someone.

Thanks for all another answers.