Develop Reference

Send request to an other android device in a app

I am currently trying to make a personal location application between 2 devices on Android.
The concept is simple: I install my application on my phone as well as on that of my wife and each can geolocate the other.
(This application is strictly personal)
To achieve this, I thought of using sending notifications by FCM.
Telephone A sends a request to telephone B which listens via a service for the reception of a message.
When phone B receives the request, it returns the GPS coordinates via FCM so that phone A displays them on a MAP.
(I also have the possibility to store the coordinates in a database instead of sending back an FCM message)
But FCM's documentation says:
"When your app is in the background, notification messages are displayed in the system tray, and onMessageReceived is not called. For notification messages with a data payload, the notification message is displayed in the system tray, and the data that was included with the notification message can be retrieved from the intent launched when the user taps on the notification."
Of course, this reduces the scope since it forces the user of the phone receiving the notification to click on it to activate the actions of the service.
Can FCM still meet my needs through another channel?
Are there other options to send a "request" to another phone?
(I know that this kind of application exists on the PlayStore, but I want to try to make mine :-))

The key word in that section from the documentation you quote is notification messages. Firebase Cloud Messaging supports two types of messages:
Notification messages, which are display by the system when the app is inactive - and delivered to your application code when the app is active.
Data messages, which are always delivered to your application code.
It sounds like you'll want to use data messages for this use-case

Know if the app received the notification from server side

I'm building a newspaper-like app and I would like to know how many people received the article's push notification vs how many actually read it.
I was thinking to implement a way in which when the notification is received the app wakes up and send a request to the server saying "Hi I'm _____, I've received the notification of the article ____" and store it in the database. Then afterwards if the user click on the notification and goes to read the article I send another request saying "Hi I'm ____ and I've read the article _____" and I also store it on the database. Afterwards with some queries I'm able to understand the percentage read/received.
I don't understand if it's even possible to wake up the app even if it was not opened by the user in a while and send a request to the server (for background is meant that the application is not launched or that is in the cache ?).
I would like to achieve what they did with Whatsapp:
I receive a new message on Whatsapp
I don't open the app
I go to WhatsApp Web
I open the conversation on WhatsApp Web
The badge and the notification on the phone goes away because I read it somewhere else
I think that that feature is achieved with silent push notifications that just update the app badge and clear the read notification.

Thats a very nice question on how to implement such silent notifications. There are few variables here that we need to consider and deal them in a different way.
Push notifications sent to the users - Some of them would have received it, Some may not have received it at all.
Pushing multiple notifications to the same user in a small amount of time - It becomes difficult here to track the exact notification user opened the app. Because user might have read all the news that received notifications in a single attempt.
The actual content displayed to the user in the app - User might have opened the app because of notifications. Some times he might have seen the notifications and then opened the app directly without interacting with the notifications.
So this is how the implementation can be.
Implement push notifications for the app
User receives the push notifications and the notification badge shows Number (1).
Now when the user views the same news story in any other medium (Your own Mac App or PC app). Server is notified of the users action and the news he/she/whoever just read.
Now the server knows it has sent a notification and it is not read. When you receive the read notification, you can send a remote notification that can be handled by the app in background and update the badge.
Check out this link for more details on how to handle notifications in various modes.
Apple documentation also can be referred here for background mode - remote-notification.
So you will be making your app run in background with certain settings to respond to silent notifications and update the badge just like WhatsApp. I hope this helps.

I've already implemented such thing in one of my app, and it's actually tricky.
You'll have a lot of use cases to handle.
First thing (but you seem to already know it): Apple does not provide
any callback to say : "this notification was sent"
Second thing : when your app is killed (not even in background), nothing at all can be done with your notification, meaning your app won't be able to wake up and read the notification, and therefor do something. The only thing you can do is changing the badge number, even if your app is killed.
Third thing : when your app is in background, you can wake up your app during 30sec. During that time you can send a request to the server, but if it takes too long, the process will be killed by the OS.
Saying that, here is a quick explanation of how you could implement the system:
You'll need on the server side to save in your data base any notifications that were sent. As soon as they are sent, save them as "pending"
On the app side: if your app is in background, as soon as the notification is received, you can wake up your app to send a request to the server. Then in your data base, your notification status will change to "receive" or "notified". If your app was killed, when the user launch your app, send a request to the server to ask for all notification in "pending" state, that way your app will be up to date, as well as your badge number.
If the user click on the notification, this will open your app directly on the article, that way you'll be able to send a request and say to your server that the article was received and read.
If the user read your article on the web side, send a notification. Set the notification badge number with the number of actual "pending" notification in your data base.
Hope this will help you in addition of the answer of #Prav :)

try this Notification Listner service https://github.com/kpbird/NotificationListenerService-Example.

Reply from Apple Developer Technical Support:
Hello Matteo,
Thank you for contacting Apple Developer Technical Support (DTS). Our engineers have reviewed your request and have concluded that there is no supported way to achieve the desired functionality given the currently shipping system configurations.
So at the end of the games IT'S NOT POSSIBLE

You want to sync your app with web app or website than once you send notification to application than set notification to particular ID.If user read that message from your web then send push notification again with different message and handle in service or broadcast receiver after that cancel notification if received message contains different message.you can also use Notification Listener.Refer thislink
Refer this link for ios.

Hi #Smile Applications after reading your question I would suggest you see OneSignal website. OneSignal will allow you to send notifications to your subscribed users. It will also show you how many users are using your app and how many of them have received your notifications. If you want to send notifications and track them from the app itself you can use their API. It is easy and I have implemented this in Android and soon will be implementing in IOS.
Now the second part of your question about knowing how to track how many users have read/opened your notification and on which activity they are on you can use Google Analytics. It will allow you to see from which part of the world your users are using your app and which activities of your app are being opened most. It is also easy and I have implemented this also in Android and soon will be implementing in IOS too.

Google Firebase Notifications for Android - when app is not running

I am trying to implement a functionality wherein users get notification messages even when the app is not running (neither in foreground nor in background). Companies like Amazon do send notifications and they show up in the notification tray - when tapped, the app opens or whatever intent the message carried with it.
I have been able to implement notification handling when the app is in foreground and background... but when the app is not running, there are no notification messages received at all!
From what I searched around, I think there needs to be a Service running in the background that keeps listening to notification messages - because a service is destroyed when the app is closed. Am I going in the right direction?
Can someone point me to some code that implements or highlights the same.

FIXED... actually.. the problem was MIUI.. Its security app by default disabled autostart for apps.. which blocks notifications from being shown in the system tray when the app is not running.
References:-
http://en.miui.com/thread-37783-1-1.html
https://github.com/firebase/quickstart-android/issues/89#issuecomment-233558184

I you have to see the implementation of FCM for android from https://firebase.google.com/docs/cloud-messaging/
I shows complete understanding of instant notification.

GCM Pushnotification not received, though GCM server reported as sent successfully

So, I am sending push notification to thousands of my users. I have noticed that GCM server respond back with "messageId" and according to the documentation it is successfully sent to the user, but the user (one of our internal device) did not receive the notification. And this happens very randomly, same device receives the notification sometimes. Is this normal? if not what could be the possible reason behind this and what would be the fix?
Thanks
Riz

Though not a complete list, the issue could be any of the following:
The affected phones were not online/connected at the time of the message being sent.
Your setup uses a collapse key, which would collapse prior messages being sent under the same collapse key (thus the reason your device only receives some notifications and not all).
The affected phones were asleep/locked, and you did not implement a Wakeful Broadcast Receiver in your client app.

GCM notification is not received when App is not running

i'v implemented GCM and it works fine except one issue.
if application works in foreground or background notification are consumed by application. However, if notification received while application is killed. Than notification only shown in top bar. But application cant find it even when user launch app.
I notice when message is recived after rebooting device, message is shown ony on message center, but its not found by application. Than, after application started, than, it start to receive messages.

Than notification only shown in top bar.
You put that Notification there yourself. GCM does not display a Notification on its own.
But application cant find it even when user launch app.
The application "found" it to display the Notification.