I am having problem sending notification to specific devices with FCM.
This is how I get the specific device ID
Add Class in Android Project: FirebaseMessagingServiceDelegate.cs
[Service]
[IntentFilter(new[] { "com.google.firebase.MESSAGING_EVENT" })]
public class FirebaseMessagingServiceDelegate : FirebaseMessagingService
{
public async override void OnNewToken(string p0)
{
base.OnNewToken(p0);
var instanceIdResult = await FirebaseInstanceId.Instance.GetInstanceId().AsAsync<IInstanceIdResult>();
var token = instanceIdResult.Token;//(Token Devices)
}
}
Each time the user opens the App: var token = instanceIdResult.Token; will be changed. So every time I have to update the token on my server? Does this mean I also create a Class on Project iOS?
And this is how I send notifications to specific device:
PageOne.xaml.cs
protected void SendNotify()
{
// This registration token comes from the client FCM SDKs.
var registrationToken = "Token Devices";
// See documentation on defining a message payload.
var message = new Message()
{
Token = registrationToken,
Notification = new Notification()
{
Title = "Test from code",
Body = "Here is your test!"
}
};
// Send a message to the device corresponding to the provided
// registration token.
string response = FirebaseMessaging.DefaultInstance.SendAsync(message).Result;
// Response is a message ID string.
Console.WriteLine("Successfully sent message: " + response);
}
I received the error: Notification does not contain a definition for "Body"
I searched and found this article: firebase send notification from server c#. However I want to send directly from Xamarin App.
Hoping for any help. Thank you!
I have been trying to read the official docs and guides about how to send message from one device to another. I have saved registration token of both devices in the Real Time Database, thus I have the registration token of another device.
I have tried the following way to send the message
RemoteMessage message = new RemoteMessage.Builder(getRegistrationToken())
.setMessageId(incrementIdAndGet())
.addData("message", "Hello")
.build();
FirebaseMessaging.getInstance().send(message);
However this is not working. The other device doesn't receive any message. I am not even sure, if I can use upstream message sending to conduct device to device communication.
PS: I just want to know if device-to-device messaging is possible using FCM? If yes, then is the code I used have some issue? If yes, then what is the correct way.
Update:
My question was to ask whether device to device messaging without using any separate server other than firebase could messaging is possible or not, if yes than how, since there's no documentation about it. I do not understand what is left to explain here? Anyways I got the answer and will update it as an answer once the question gets reopened.
Firebase has two features to send messages to devices:
the Notifications panel in your Firebase Console allows you to send notifications to specific devices, groups of users, or topics that users subscribed to.
by calling Firebase Cloud Messaging API, you can send messages with whatever targeting strategy you prefer. Calling the FCM API requires access to your Server key, which you should never expose on client devices. That's why you should always run such code on an app server.
The Firebase documentation shows this visually:
Sending messages from one device directly to another device is not supported through the Firebase Cloud Messaging client-side SDKs.
Update: I wrote a blog post detailing how to send notifications between Android devices using Firebase Database, Cloud Messaging and Node.js.
Update 2: You can now also use Cloud Functions for Firebase to send messages securely, without spinning up a server. See this sample use-case to get started. If you don't want to use Cloud Functions, you can run the same logic on any trusted environment you already have, such as your development machine, or a server you control.
Warning There is a very important reason why we don't mention this approach anywhere. This exposes your server key in the APK that
you put on every client device. It can (and thus will) be taken from
there and may lead to abuse of your project. I highly recommend
against taking this approach, except for apps that you only put on
your own devices. – Frank van Puffelen
Ok, so the answer by Frank was correct that Firebase does not natively support device to device messaging. However there's one loophole in that. The Firebase server doesn't identify whether you have send the request from an actual server or are you doing it from your device.
So all you have to do is send a Post Request to Firebase's messaging server along with the Server Key. Just keep this in mind that the server key is not supposed to be on the device, but there's no other option if you want device-to-device messaging using Firebase Messaging.
I am using OkHTTP instead of default way of calling the Rest API. The code is something like this -
public static final String FCM_MESSAGE_URL = "https://fcm.googleapis.com/fcm/send";
OkHttpClient mClient = new OkHttpClient();
public void sendMessage(final JSONArray recipients, final String title, final String body, final String icon, final String message) {
new AsyncTask<String, String, String>() {
#Override
protected String doInBackground(String... params) {
try {
JSONObject root = new JSONObject();
JSONObject notification = new JSONObject();
notification.put("body", body);
notification.put("title", title);
notification.put("icon", icon);
JSONObject data = new JSONObject();
data.put("message", message);
root.put("notification", notification);
root.put("data", data);
root.put("registration_ids", recipients);
String result = postToFCM(root.toString());
Log.d(TAG, "Result: " + result);
return result;
} catch (Exception ex) {
ex.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String result) {
try {
JSONObject resultJson = new JSONObject(result);
int success, failure;
success = resultJson.getInt("success");
failure = resultJson.getInt("failure");
Toast.makeText(getCurrentActivity(), "Message Success: " + success + "Message Failed: " + failure, Toast.LENGTH_LONG).show();
} catch (JSONException e) {
e.printStackTrace();
Toast.makeText(getCurrentActivity(), "Message Failed, Unknown error occurred.", Toast.LENGTH_LONG).show();
}
}
}.execute();
}
String postToFCM(String bodyString) throws IOException {
RequestBody body = RequestBody.create(JSON, bodyString);
Request request = new Request.Builder()
.url(FCM_MESSAGE_URL)
.post(body)
.addHeader("Authorization", "key=" + SERVER_KEY)
.build();
Response response = mClient.newCall(request).execute();
return response.body().string();
}
I hope Firebase will come with a better solution in future. But till then, I think this is the only way. The other way would be to send topic message or group messaging. But that was not in the scope of the question.
Update:
The JSONArray is defined like this -
JSONArray regArray = new JSONArray(regIds);
regIds is a String array of registration ids, you want to send this message to. Keep in mind that the registration ids must always be in an array, even if you want it to send to a single recipient.
I have also been using direct device to device gcm messaging in my prototype. It has been working very well. We dont have any server. We exchange GCM reg id using sms/text and then communicate using GCM after that. I am putting here code related to GCM handling
**************Sending GCM Message*************
//Sends gcm message Asynchronously
public class GCM_Sender extends IntentService{
final String API_KEY = "****************************************";
//Empty constructor
public GCM_Sender() {
super("GCM_Sender");
}
//Processes gcm send messages
#Override
protected void onHandleIntent(Intent intent) {
Log.d("Action Service", "GCM_Sender Service Started");
//Get message from intent
String msg = intent.getStringExtra("msg");
msg = "\"" + msg + "\"";
try{
String ControllerRegistrationId = null;
//Check registration id in db
if(RegistrationIdAdapter.getInstance(getApplicationContext()).getRegIds().size() > 0 ) {
String controllerRegIdArray[] = RegistrationIdAdapter.getInstance(getApplicationContext()).getRegIds().get(1);
if(controllerRegIdArray.length>0)
ControllerRegistrationId = controllerRegIdArray[controllerRegIdArray.length-1];
if(!ControllerRegistrationId.equalsIgnoreCase("NULL")){
// 1. URL
URL url = new URL("https://android.googleapis.com/gcm/send");
// 2. Open connection
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
// 3. Specify POST method
urlConnection.setRequestMethod("POST");
// 4. Set the headers
urlConnection.setRequestProperty("Content-Type", "application/json");
urlConnection.setRequestProperty("Authorization", "key=" + API_KEY);
urlConnection.setDoOutput(true);
// 5. Add JSON data into POST request body
JSONObject obj = new JSONObject("{\"time_to_live\": 0,\"delay_while_idle\": true,\"data\":{\"message\":" + msg + "},\"registration_ids\":[" + ControllerRegistrationId + "]}");
// 6. Get connection output stream
OutputStreamWriter out = new OutputStreamWriter(urlConnection.getOutputStream());
out.write(obj.toString());
out.close();
// 6. Get the response
int responseCode = urlConnection.getResponseCode();
BufferedReader in = new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null){
response.append(inputLine);
}
in.close();
Log.d("GCM getResponseCode:", new Integer(responseCode).toString());
}else{
Log.d("GCM_Sender:","Field REGISTRATION_TABLE is null");
}
}else {
Log.d("GCM_Sender:","There is no Registration ID in DB ,please sync devices");
}
} catch (Exception e) {
e.printStackTrace();
//MessageSender.getInstance().sendMessage(msg, Commands.SMS_MESSAGE);
}
}
//Called when service is no longer alive
#Override
public void onDestroy() {
super.onDestroy();
//Do a log that GCM_Sender service has been destroyed
Log.d("Action Service", "GCM_Sender Service Destroyed");
}
}
**************Receiving GCM Message*************
public class GCM_Receiver extends WakefulBroadcastReceiver {
public static final String RETRY_ACTION ="com.google.android.c2dm.intent.RETRY";
public static final String REGISTRATION ="com.google.android.c2dm.intent.REGISTRATION";
public SharedPreferences preferences;
//Processes Gcm message .
#Override
public void onReceive(Context context, Intent intent) {
ComponentName comp = new ComponentName(context.getPackageName(),
GCMNotificationIntentService.class.getName());
//Start GCMNotificationIntentService to handle gcm message asynchronously
startWakefulService(context, (intent.setComponent(comp)));
setResultCode(Activity.RESULT_OK);
/*//Check if DatabaseService is running .
if(!DatabaseService.isServiceRunning) {
Intent dbService = new Intent(context,DatabaseService.class);
context.startService(dbService);
}*/
//Check if action is RETRY_ACTION ,if it is then do gcm registration again .
if(intent.getAction().equals(RETRY_ACTION)) {
String registrationId = intent.getStringExtra("registration_id");
if(TextUtils.isEmpty(registrationId)){
DeviceRegistrar.getInstance().register(context);
}else {
//Save registration id to prefs .
preferences = PreferenceManager.getDefaultSharedPreferences(context);
SharedPreferences.Editor editor = preferences.edit();
editor.putString("BLACKBOX_REG_ID",registrationId);
editor.commit();
}
} else if (intent.getAction().equals(REGISTRATION)) {
}
}
}
//Processes gcm messages asynchronously .
public class GCMNotificationIntentService extends IntentService{
public static final int NOTIFICATION_ID = 1;
private NotificationManager mNotificationManager;
String gcmData;
private final String TAG = "GCMNotificationIntentService";
//Constructor with super().
public GCMNotificationIntentService() {
super("GcmIntentService");
}
//Called when startService() is called by its Client .
//Processes gcm messages .
#Override
protected void onHandleIntent(Intent intent) {
Log.d("GCMNotificationIntentService", "GCMNotificationIntentService Started");
Bundle extras = intent.getExtras();
//Get instance of GoogleCloudMessaging .
GoogleCloudMessaging gcm = GoogleCloudMessaging.getInstance(this);
//Get gcm message type .
String messageType = gcm.getMessageType(intent);
if (!extras.isEmpty()) {
if (GoogleCloudMessaging.MESSAGE_TYPE_SEND_ERROR
.equals(messageType)) {
sendNotification("Send error: " + extras.toString());
} else if (GoogleCloudMessaging.MESSAGE_TYPE_DELETED
.equals(messageType)) {
sendNotification("Deleted messages on server: "
+ extras.toString());
} else if (GoogleCloudMessaging.MESSAGE_TYPE_MESSAGE
.equals(messageType)) {
Log.i(TAG, "Completed work # " + SystemClock.elapsedRealtime());
gcmData = extras.getString("message");
Intent actionService = new Intent(getApplicationContext(),Action.class);
actionService.putExtra("data", gcmData);
//start Action service .
startService(actionService);
//Show push notification .
sendNotification("Action: " + gcmData);
//Process received gcmData.
Log.d(TAG,"Received Gcm Message from Controller : " + extras.getString("message"));
}
}
GCM_Receiver.completeWakefulIntent(intent);
}
//Shows notification on device notification bar .
private void sendNotification(String msg) {
mNotificationManager = (NotificationManager) this.getSystemService(Context.NOTIFICATION_SERVICE);
Intent notificationIntent = new Intent(this, BlackboxStarter.class);
//Clicking on GCM notification add new layer of app.
notificationIntent.setFlags( Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);
PendingIntent contentIntent = PendingIntent.getActivity(this, 0,notificationIntent, PendingIntent.FLAG_CANCEL_CURRENT);
NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(
this).setSmallIcon(R.drawable.gcm_cloud)
.setContentTitle("Notification from Controller")
.setStyle(new NotificationCompat.BigTextStyle().bigText(msg))
.setContentText(msg);
mBuilder.setContentIntent(contentIntent);
mNotificationManager.notify(NOTIFICATION_ID, mBuilder.build());
//Play default notification
try {
Uri notification = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
Ringtone r = RingtoneManager.getRingtone(getApplicationContext(), notification);
r.play();
} catch (Exception e) {
e.printStackTrace();
}
}
//Called when service is no longer be available .
#Override
public void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
Log.d("GCMNotificationIntentService", "GCMNotificationIntentService Destroyed");
}
}
According to the new documentation which was updated on October 2, 2018 you must send post request as below
https://fcm.googleapis.com/fcm/send
Content-Type:application/json
Authorization:key=AIzaSyZ-1u...0GBYzPu7Udno5aA //Server key
{
"to": "sent device's registration token",
"data": {
"hello": "message from someone",
}
}
To get device's registration token extend FirebaseMessagingService and override onNewToken(String token)
For more info refer to doc https://firebase.google.com/docs/cloud-messaging/android/device-group
I am late but above solutions has helped me to write down this simple answer, you can send your message directly to android devices from android application, here is the simple implementation I have done and it works great for me.
compile android volley library
compile 'com.android.volley:volley:1.0.0'
Just copy paste this simple function ;) and your life will become smooth just like knife in butter. :D
public static void sendPushToSingleInstance(final Context activity, final HashMap dataValue /*your data from the activity*/, final String instanceIdToken /*firebase instance token you will find in documentation that how to get this*/ ) {
final String url = "https://fcm.googleapis.com/fcm/send";
StringRequest myReq = new StringRequest(Request.Method.POST,url,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
Toast.makeText(activity, "Bingo Success", Toast.LENGTH_SHORT).show();
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(activity, "Oops error", Toast.LENGTH_SHORT).show();
}
}) {
#Override
public byte[] getBody() throws com.android.volley.AuthFailureError {
Map<String, Object> rawParameters = new Hashtable();
rawParameters.put("data", new JSONObject(dataValue));
rawParameters.put("to", instanceIdToken);
return new JSONObject(rawParameters).toString().getBytes();
};
public String getBodyContentType()
{
return "application/json; charset=utf-8";
}
#Override
public Map<String, String> getHeaders() throws AuthFailureError {
HashMap<String, String> headers = new HashMap<String, String>();
headers.put("Authorization", "key="+YOUR_LEGACY_SERVER_KEY_FROM_FIREBASE_CONSOLE);
headers.put("Content-Type","application/json");
return headers;
}
};
Volley.newRequestQueue(activity).add(myReq);
}
Note
If you want to send message to topics so you can change parameter instanceIdToken to something like /topics/topicName.
For groups implementation is the same but you just need to take care of parameters. checkout Firebase documentation and you can pass those parameters.
let me know if you face any issue.
I am writing an Xamarin.forms based app which is currently running on android platform. It is the first time I need to use push-notifications. I followed a guide from microsoft (https://learn.microsoft.com/de-de/xamarin/android/data-cloud/google-messaging/remote-notifications-with-fcm?tabs=vswin)") to implement the notifications.
The target android version is 8.1 API 27. The app runs on a Samsung tab active 2, which has android 8.1.
I configured the app as seen in the tutorial. I push the messages through a defined channel and this channel is subscribed in the app. The messages are pushed by a server which triggers the rest call for the FCM api. The first day I did some tests the transmission worked very good and I would say it was (nearly) reliable.
The next day I implemented some other features and wanted to test the push notifications again. Then: I was very confused, the most messages were not delivered or VERY VERY late. I am not sure if all messages were transmitted, there went may be some lost.
For me the FCM service is a big blackbox where I can delegate some work and then I need to hope that the messages will be transmitted. I am very confused now.
I paste here some code, but it is nearly what you can find in the tutorial:
My Questions:
What can I do? Is there something to get some more information from the FCM what my messages are currently doing? Or are there some problems with the code?
This is run in the mainActivity:
if (this.IsPlayServicesAvailable())
{
// Creates a notification channel
this.CreateNotificationChannel();
//Console.WriteLine("InstanceID token: " + FirebaseInstanceId.Instance.Token);
// Subscribe to notification token
FirebaseMessaging.Instance.SubscribeToTopic("channel");
Log.Debug(TAG, "Subscribed to remote notifications");
}
This checks if the channel can be created and creates it: (is called in the mainActivity)
private void CreateNotificationChannel()
{
// The app is not running on Android 8.0 or higher
if (Build.VERSION.SdkInt < BuildVersionCodes.O)
{
// Notification channels are new in API 26 (and not a part of the
// support library). There is no need to create a notification
// channel on older versions of Android.
return;
}
// Create a notification channel for publishing notifications
var channel = new NotificationChannel(CHANNEL_ID, "FCM Notifications", NotificationImportance.Default)
{
Description = "Firebase Cloud Messages appear in this channel"
};
var notificationManager = (NotificationManager)GetSystemService(Android.Content.Context.NotificationService);
notificationManager.CreateNotificationChannel(channel);
}
This checks if playServices are available: (also called in mainActivity)
public bool IsPlayServicesAvailable()
{
int resultCode = GoogleApiAvailability.Instance.IsGooglePlayServicesAvailable(this);
if (resultCode != ConnectionResult.Success)
{
if (GoogleApiAvailability.Instance.IsUserResolvableError(resultCode))
{
Log.Debug(TAG, GoogleApiAvailability.Instance.GetErrorString(resultCode));
}
else
{
Log.Debug(TAG, "This device has no compatible Google Play services APK - Download an APK from the Google Play Store or to enable it in the device's system settings!");
Finish();
}
return false;
}
else
{
Log.Debug(TAG, "Google Play Services are available.");
return true;
}
}
The last snipped is the service to handle a notification and inform the user:
[Service]
[IntentFilter(new[] { "com.google.firebase.MESSAGING_EVENT" })]
public class CustomFirebaseMessagingService : FirebaseMessagingService
{
// Logging Tag
private static readonly string TAG = "CustomFirebaseMessagingService";
/* Handles data messages and notifications messages if the app is in foreground.
*
* Apps only have 10 seconds in which to handle an incoming Firebase Cloud Message.
* Any work that takes longer than this should be scheduled for background execution using a library such as the 'Android Job Scheduler' or the 'Firebase Job Dispatcher'.
*
*/
public override void OnMessageReceived(RemoteMessage message)
{
Log.Debug(TAG, "Message from: " + message.From);
// If the message data payload is not empty, display a notification
if (message.Data.Count > 0)
{
Log.Debug(TAG, "Data Payload: " + message.Data.ToString());
this.SendNotification(message.Data);
}
}
// Converts the incoming FCM message into a local notification
private void SendNotification(IDictionary<string, string> data)
{
Console.WriteLine("Push Message received");
var intent = new Intent(this, typeof(MainActivity));
intent.AddFlags(ActivityFlags.ClearTop);
if (data.TryGetValue("message", out string message))
{
foreach (var key in data.Keys)
{
intent.PutExtra(key, data[key]);
}
var pendingIntent = PendingIntent.GetActivity(this, MainActivity.NOTIFICATION_ID, intent, PendingIntentFlags.OneShot);
var notificationBuilder = new NotificationCompat.Builder(this, MainActivity.CHANNEL_ID)
.SetSmallIcon(Resource.Drawable.NotificationIcon)
.SetContentTitle("TITEL")
.SetContentText(message)
.SetAutoCancel(true)
.SetContentIntent(pendingIntent);
var notificationManager = NotificationManagerCompat.From(this);
notificationManager.Notify(MainActivity.NOTIFICATION_ID, notificationBuilder.Build());
}
}
}
When I open app by tapping on FCM push notification, The API service calls I am making by using await keyword those are not working. Entire app not returning data.
Code for API calling
var result = await objHomework.GetHomeWorksForStudentPagesAsync(studentId.ToString());
result returning null. if app already open, everything working fine. See the Image below screenshot of app
Notification messages are delivered to OnMessageReceived callback only when the app is in the foreground.
Override the HandleIntent Method of the FirebaseMessageService to work for background as well
public override void HandleIntent(Intent intent)
{
try
{
if (intent.Extras != null)
{
var builder = new RemoteMessage.Builder("MyFirebaseMessagingService");
foreach (string key in intent.Extras.KeySet())
{
builder.AddData(key, intent.Extras.Get(key).ToString());
}
this.OnMessageReceived(builder.Build());
}
else
{
base.HandleIntent(intent);
}
}
catch (Exception)
{
base.HandleIntent(intent);
}
}
Actually, I was missing some keys which is necessary for service call authentication in my project. I am getting those keys in MaiActivity but notification click even starting app from somewhere else therefore keys values was null and service calls was not happening.
I am sending Push notification from Azure Notification hub. I want to navigate to particular page on tap of received Toast Push Notification. I am receiving Push notification but unable to navigate to a particular page.
Here is my insert code:
function insert(item, user, request) {
var payload = '<?xml version="1.0" encoding="utf-8"?><toast><visual>' +
'<binding template="ToastText01"> <text id="1">' +
item.subject + '</text></binding></visual></toast>';
request.execute({
success: function () {
// If the insert succeeds, send a notification.
push.wns.send(null, payload, 'wns/toast', {
success: function (pushResponse) {
console.log("Sent push:", pushResponse);
request.respond();
},
error: function (pushResponse) {
console.log("Error Sending push:", pushResponse);
request.respond(500, { error: pushResponse });
}
});
}
});
}
Can any one please help?
There is a number of steps here and you didn't give very much detail on your problem. I'll try to explain the concept in full of anyone who might need the whole thing. Be sure you've set up all the steps in this article first: https://azure.microsoft.com/en-us/documentation/articles/mobile-services-javascript-backend-windows-phone-get-started-push/
First, you need to send the push notification with the page you want to load. So let's say you have a page that shows some details about an item. When you get a push notification, it automatically opens up that item. You could send a payload like:
var payload = '<?xml version="1.0" encoding="utf-8"?><toast><visual>' +
'<binding template="ToastText01"> <text id="1">' +
item.id + '</text></binding></visual></toast>';
Then you need to respond to the push notification. You can see the documentation page for this here: https://msdn.microsoft.com/en-us/library/hh221550.aspx
Your set up code would look something like this:
ShellToastNotificationReceived +=
new EventHandler<NotificationEventArgs>(httpChannel_ShellToastNotificationReceived);
public static HttpNotificationChannel CurrentChannel { get; private set; }
// This is from the tutorial linked in the first paragraph
private void AcquirePushChannel()
{
CurrentChannel = HttpNotificationChannel.Find("MyPushChannel");
if (CurrentChannel == null)
{
CurrentChannel = new HttpNotificationChannel("MyPushChannel");
CurrentChannel.Open();
CurrentChannel.BindToShellToast();
}
CurrentChannel.ChannelUriUpdated +=
new EventHandler<NotificationChannelUriEventArgs>(async (o, args) =>
{
// Register for notifications using the new channel
await MobileService.GetPush()
.RegisterNativeAsync(CurrentChannel.ChannelUri.ToString());
});
CurrentChannel.ShellToastNotificationReceived +=
new EventHandler<NotificationEventArgs(async (o, args) =>
{
RootFrame.Navigate(new Uri("/ItemPage.xaml"), args.Collection['1']);
});
}
I haven't tested any of this code, but it should be good enough to point you in the right directions. Basically,
Send the info you need to react in the Push Notification
Listen for event on your Client
Navigate to the frame you want to be on
Be sure to checkout this tutorial on Navigation: https://msdn.microsoft.com/en-us/library/windows/apps/xaml/hh771188.aspx