How to implement a notification system for the user after a successful file download?

To implement a notification system after successfully downloading a file on Android, you can use the NotificationManager class. After the file download is complete, create a notification to inform the user. Example in Kotlin:

val notificationManager = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager

val notification = NotificationCompat.Builder(this, CHANNEL_ID)
    .setSmallIcon(R.drawable.ic_download_done)
    .setContentTitle("Download Complete")
    .setContentText("File downloaded successfully")
    .setPriority(NotificationCompat.PRIORITY_HIGH)
    .build()

notificationManager.notify(NOTIFICATION_ID, notification)

It is important to create a notification channel beforehand for Android 8.0 and above. The notification can be shown immediately after confirming the successful download of the file.