Foreground Services in Android: Long-Running Tasks with Notifications

#android #kotlin #compose #tutorial

Foreground Services let your app perform important tasks that users are aware of, with persistent notifications. This is essential for tracking, timers, and location services.

Creating a Foreground Service

Declare the service in AndroidManifest.xml:

<service
    android:name=".LocationTrackingService"
    android:foregroundServiceType="location" />
<uses-permission android:name="android.permission.FOREGROUND_SERVICE_LOCATION" />

Service Implementation with Notification

class LocationTrackingService : Service() {
    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
        val notification = NotificationCompat.Builder(this, CHANNEL_ID)
            .setContentTitle("Location Tracking")
            .setContentText("Your location is being tracked")
            .setSmallIcon(R.drawable.ic_location)
            .setOngoing(true)
            .setPriority(NotificationCompat.PRIORITY_LOW)
            .build()

        startForeground(NOTIFICATION_ID, notification)

        lifecycleScope.launchWhenStarted {
            trackLocation()
        }
        return START_STICKY
    }

    private suspend fun trackLocation() {
        // Your location tracking logic
    }
}

Starting a Foreground Service from Compose

@Composable
fun TimerScreen() {
    Button(
        onClick = {
            val intent = Intent(context, TimerService::class.java)
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
                context.startForegroundService(intent)
            } else {
                context.startService(intent)
            }
        }
    ) {
        Text("Start Timer")
    }
}

Updating Notification from Service

Keep users informed with dynamic notification updates:

private fun updateNotification(timeRemaining: Long) {
    val notification = NotificationCompat.Builder(this, CHANNEL_ID)
        .setContentTitle("Timer")
        .setContentText("$timeRemaining seconds remaining")
        .setProgress(100, progress, false)
        .build()

    notificationManager.notify(NOTIFICATION_ID, notification)
}