How to make notification every 7 p.m?

Question

Hello guys i'm making app for tracking insulin injections for my mom. I want to make app that will create notification automatically every 7 p.m. Can you advice me how to do it? I tried to google it but i'm only found videos with notifications by clicking button but it will not work for me because i want my app to create notifications even when app is closed so i need something like Services that will always by alive even app is closed

Answer 1

You firstly need to instantiate a Broadcast Receiver class and override their onReceive function.

1. Don't forget to add this to your manifest.

   <receiver android:name=".AlertReceiver" />

2. Override the function as talked.

   class AlertReceiver : BroadcastReceiver() {
   
    override fun onReceive(context: Context, intent: Intent) {
        Glide.with(context).asBitmap().load(R.drawable.ic_diagnosis_24dp).into(object : CustomTarget<Bitmap>() {
            override fun onLoadCleared(placeholder: Drawable?) {}
            override fun onResourceReady(resource: Bitmap, transition: Transition<in Bitmap>?) {
                val notificationHelper = NotificationHelper(context,resource,intent.extras!!.getInt("requestCode"))
                val nb = notificationHelper.channelNotification
                notificationHelper.manager?.notify(1, nb.build())
            }
        })
      }
   }
   

3. You can prepare a Notification Helper just in case you want to deal with things in a better format.

   class NotificationHelper(base: Context?, healthReportIcon: Bitmap, requestCode: Int) : ContextWrapper(base) {
   
    private val healthIcon = healthReportIcon
    private var mManager: NotificationManager? = null
    private lateinit var beforeTime: String
    private var intentActivity: Class<*>
   
    @TargetApi(Build.VERSION_CODES.O)
    private fun createChannel() {
        val channel = NotificationChannel(channelID, channelName, NotificationManager.IMPORTANCE_HIGH)
        manager!!.createNotificationChannel(channel)
    }
   
    val manager: NotificationManager? get() {
        if (mManager == null) {
            mManager = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
        }
        return mManager
    }
   
    val channelNotification: NotificationCompat.Builder get() = NotificationCompat.Builder(applicationContext, channelID)
        .setContentTitle("Reminder!")
        .setContentText("Update medical records before $beforeTime")
        .setSmallIcon(R.drawable.ic_round_local_hospital_24)
        .setColor(ContextCompat.getColor(this,R.color.blue_diff))
        .setLargeIcon(healthIcon)
        .setDefaults(NotificationCompat.DEFAULT_ALL)
        .setSound(RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION))
        .setPriority(NotificationCompat.PRIORITY_MAX)
        .setTimeoutAfter(1800000)
        .setAutoCancel(true)
        .setContentIntent(PendingIntent.getActivity(baseContext, 0, Intent(baseContext, intentActivity), 0))
   
    companion object {
        const val channelID = "phoneId"
        const val channelName = "phoneChannel"
    }
   
    init {
        when (requestCode) {
            0 -> {
                beforeTime = "12:30 AM"
            }
            1 -> {
                beforeTime = "6:30 AM"
            }
            2 -> {
                beforeTime = "12:30 PM"
            }
            3 -> {
                beforeTime = "6:30 PM"
            }
        }
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            createChannel()
        }
        intentActivity = if(FirebaseAuth.getInstance().currentUser!=null) {
            HomeActivity::class.java
        } else{
            Splash::class.java
        }
    }
   }
   

4. Finally, set or cancel your alarms in your codebase.

   private fun startAlarms() {
        val cal0 = Calendar.getInstance()
        cal0[Calendar.HOUR_OF_DAY]=24
        cal0[Calendar.MINUTE]=0
        cal0[Calendar.SECOND]=0
   
        val cal1 = Calendar.getInstance()
        cal1[Calendar.HOUR_OF_DAY]=6
        cal1[Calendar.MINUTE]=0
        cal1[Calendar.SECOND]=0
   
        val cal2 = Calendar.getInstance()
        cal2[Calendar.HOUR_OF_DAY]=12
        cal2[Calendar.MINUTE]=0
        cal2[Calendar.SECOND]=0
   
        val cal3 = Calendar.getInstance()
        cal3[Calendar.HOUR_OF_DAY]=18
        cal3[Calendar.MINUTE]=0
        cal3[Calendar.SECOND]=0
   
        if (cal0.before(Calendar.getInstance())) {
            cal0.add(Calendar.DATE, 1)
        }
        if (cal1.before(Calendar.getInstance())) {
            cal1.add(Calendar.DATE, 1)
        }
        if (cal2.before(Calendar.getInstance())) {
            cal2.add(Calendar.DATE, 1)
        }
        if (cal3.before(Calendar.getInstance())) {
            cal3.add(Calendar.DATE, 1)
        }
   
        val alarmManager: AlarmManager = getSystemService(Context.ALARM_SERVICE) as AlarmManager
   
        val intent = Intent(this, AlertReceiver::class.java)
   
        intent.putExtra("requestCode",0)
        alarmManager.setExact(AlarmManager.RTC_WAKEUP, cal0.timeInMillis, PendingIntent.getBroadcast(this, 0,intent , PendingIntent.FLAG_UPDATE_CURRENT))
        intent.putExtra("requestCode",1)
        alarmManager.setExact(AlarmManager.RTC_WAKEUP, cal1.timeInMillis, PendingIntent.getBroadcast(this, 1, intent, PendingIntent.FLAG_UPDATE_CURRENT))
        intent.putExtra("requestCode",2)
        alarmManager.setExact(AlarmManager.RTC_WAKEUP, cal2.timeInMillis, PendingIntent.getBroadcast(this, 2,intent, PendingIntent.FLAG_UPDATE_CURRENT))
        intent.putExtra("requestCode",3)
        alarmManager.setExact(AlarmManager.RTC_WAKEUP, cal3.timeInMillis, PendingIntent.getBroadcast(this, 3, intent, PendingIntent.FLAG_UPDATE_CURRENT))
    }
    private fun cancelAlarms() {
        val alarmManager: AlarmManager = getSystemService(Context.ALARM_SERVICE) as AlarmManager
        val intent = Intent(this, AlertReceiver::class.java)
   
        alarmManager.cancel(PendingIntent.getBroadcast(this, 0, intent, PendingIntent.FLAG_CANCEL_CURRENT))
        alarmManager.cancel(PendingIntent.getBroadcast(this, 1, intent, PendingIntent.FLAG_CANCEL_CURRENT))
        alarmManager.cancel(PendingIntent.getBroadcast(this, 2, intent, PendingIntent.FLAG_CANCEL_CURRENT))
        alarmManager.cancel(PendingIntent.getBroadcast(this, 3, intent, PendingIntent.FLAG_CANCEL_CURRENT))
   
        PendingIntent.getBroadcast(this, 0, intent, PendingIntent.FLAG_CANCEL_CURRENT).cancel()
        PendingIntent.getBroadcast(this, 1, intent, PendingIntent.FLAG_CANCEL_CURRENT).cancel()
        PendingIntent.getBroadcast(this, 2, intent, PendingIntent.FLAG_CANCEL_CURRENT).cancel()
        PendingIntent.getBroadcast(this, 3, intent, PendingIntent.FLAG_CANCEL_CURRENT).cancel()
    }
   

Hope this helped you out. Happy Coding! :)