Notification is not showing in Android 9 - android-notifications

Question

I am using this code to show notification in my android Application. This is working fine in all android version but no notification is showing in Android 9.
I tried to implement this with different method but nothing worked.
public void showNotification(String heading, String description, String imageUrl, Intent intent){
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
createChannel();
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0 /* Request code */, intent,
PendingIntent.FLAG_ONE_SHOT);
Uri defaultSoundUri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this,"channelID")
.setSmallIcon(R.drawable.logo)
.setContentTitle(heading)
.setContentText(description)
.setAutoCancel(true)
.setSound(defaultSoundUri)
.setContentIntent(pendingIntent);
NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
int notificationId = (int) ((new Date().getTime() / 1000L) % Integer.MAX_VALUE);
notificationManager.notify(notificationId, notificationBuilder.build());
}
public void createChannel(){
if (Build.VERSION.SDK_INT < 26) {
return;
}
NotificationManager notificationManager =
(NotificationManager) this.getSystemService(Context.NOTIFICATION_SERVICE);
NotificationChannel channel = new NotificationChannel("channelID","name", NotificationManager.IMPORTANCE_DEFAULT);
channel.setDescription("Description");
notificationManager.createNotificationChannel(channel);
}
Thanks..

Answer 1

Hi this is very Late Answer but I still want to mark the mistake in the code as well as the working code snippet so that It can help others.
you are having two instance of notificationManager on in the showNotification(..) function and another in the createChannel() function. You must create channel in the same instance of the notificationManager so your working code will be like:
public void showNotification(String heading, String description, String imageUrl, Intent intent){
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0 /* Request code */, intent,
PendingIntent.FLAG_ONE_SHOT);
Uri defaultSoundUri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this,"channelID")
.setSmallIcon(R.drawable.ic_launcher_background)
.setContentTitle(heading)
.setContentText(description)
.setAutoCancel(true)
.setSound(defaultSoundUri)
.setContentIntent(pendingIntent);
NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
int notificationId = 1;
createChannel(notificationManager);
notificationManager.notify(notificationId, notificationBuilder.build());
}
public void createChannel(NotificationManager notificationManager){
if (Build.VERSION.SDK_INT < 26) {
return;
}
NotificationChannel channel = new NotificationChannel("channelID","name", NotificationManager.IMPORTANCE_DEFAULT);
channel.setDescription("Description");
notificationManager.createNotificationChannel(channel);
}
Call Like:
showNotification("Heading","Description","",new Intent(this,MainActivity.class));
The Results: