Get reminders based on data in a database

Question

I want to get reminders for some Appointments that I have saved in database and they have a notificationTime property witch is the time when a notification needs to be displayed.

My approach so far is to write some kind of job that runs 1 or 2 times a day to pull the notifications that need to be registered in the next 24h and ofc register them (if you guys have a better ideea lmk :D )

This works BUT:

• Only if the app is in foreground / background; then I get notification every 15min or so;
• If I KILL the app I don't receive notification on my physical device (Xiaomi Redmi Note 9 Pro with Android version 12 SKQ), only on the virtual one (Pixel 5 Android 13)

Right now I have a class that extends JobService and I use JobScheduler to schedule the Job to run every 15 min (for testing so I don't need to w8 12h xD )

Here is the JobScheduler witch I call in MainActivity file in OnCreate method

 Console.WriteLine("Schedualing job");
            TimeSpan interval = TimeSpan.FromMinutes(15);

            var javaClass = Java.Lang.Class.FromType(typeof(NotificationService));
            var componentName = new ComponentName(Application.Context, javaClass);

            var jobInfo = new JobInfo.Builder(1, componentName)
                .SetPeriodic(15 * 60 * 1000, 30 * 60 * 1000)
                .SetRequiredNetworkType(NetworkType.Any)
                .SetPersisted(true)
                .Build();
            
            var jobScheduler = (JobScheduler)GetSystemService(JobSchedulerService);
            var resultCode = jobScheduler.Schedule(jobInfo);

and here is the NotificationService.cs

[Service(Name = "com.companyname.deratizare_mobile.NotificationService",
        Permission = "android.permission.BIND_JOB_SERVICE")]
    public class NotificationService : JobService
    {
        public override StartCommandResult OnStartCommand(Intent intent, StartCommandFlags flags, int startId)
        {
            return StartCommandResult.StickyCompatibility;
        }

        public override bool OnStartJob(JobParameters @params)
        {
            Console.WriteLine("Job started");
            Task.Run(async () =>
            {
                //var hasSuccessful = await ProccessNotificationToRegister();
                var notification = new NotificationRequest
                {
                    Title = "Job",
                    Description = $"Description",
                    Schedule = new NotificationRequestSchedule
                    {
                        NotifyTime = DateTime.Now,
                    }
                };

                LocalNotificationCenter.Current.Show(notification);
                JobFinished(@params, false);
            Console.WriteLine("Job finished");
            });
            return true;
        }

        public override bool OnStopJob(JobParameters @params)
        {
            Console.WriteLine("Job stopped");
            return true;
        }
}

AndroidManifest

    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.ACCESS_NOTIFICATION_POLICY" />
    <uses-permission android:name="android.permission.POST_NOTIFICATIONS" />
    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
    <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
    <uses-permission android:name="android.permission.BIND_JOB_SERVICE" />
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

UPDATE

I have given permission to auto start to my app from the device and it works

SOLUTION

I ended up using FCM and a hosted service on the server that checks the cache every 5 minutes where I have stored the next notification that needs to be displaied

Answer 1

You can try to use Firebase push notifications.

With push notifications, you can update your users without requiring the app to run at all times or having it poll a server, potentially running down the battery.

For more information, you can check Implementing Push Notifications in Your Android Apps and Firebase Cloud Messaging.