I would like to update notification data, but the only way I found is to launch a new one with the same Id.
The problem is that I don't want to raise a new one if the original has beed canceled. Is there a way to tell if a notification is visible or canceled? Or a way to update a notification only if it exists?
If you're app has a minimum API >= 23 can use this method to get active notification:
NotificationManager mNotificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
StatusBarNotification[] notifications = mNotificationManager.getActiveNotifications();
for (StatusBarNotification notification : notifications) {
if (notification.getId() == 100) {
// Do something.
}
}
This is how I solved it:
private boolean isNotificationVisible() {
Intent notificationIntent = new Intent(context, MainActivity.class);
PendingIntent test = PendingIntent.getActivity(context, MY_ID, notificationIntent, PendingIntent.FLAG_NO_CREATE);
return test != null;
}
This is how I generate the notification:
/**
* Issues a notification to inform the user that server has sent a message.
*/
private void generateNotification(String text) {
int icon = R.drawable.notifiaction_icon;
long when = System.currentTimeMillis();
NotificationManager notificationManager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
Notification notification = new Notification(icon, text, when);
String title = context.getString(R.string.app_name);
Intent notificationIntent = new Intent(context, MainActivity.class);
// set intent so it does not start a new activity
//notificationIntent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_SINGLE_TOP);
PendingIntent intent = PendingIntent.getActivity(context, MY_ID, notificationIntent, 0);
notification.setLatestEventInfo(context, title, text, intent);
notification.flags |= Notification.FLAG_AUTO_CANCEL; //PendingIntent.FLAG_ONE_SHOT
notificationManager.notify(MY_ID, notification);
}
I think you can use deleteIntent of Notification class.
I remember in one of my application I use use to fire a Broadcast (custom Broadcast) when a notification is cancelled or the Notification tray was cleared.
You can check as follow in Kotlin:
val mNotificationManager: NotificationManager = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
val notifications: Array<StatusBarNotification> = mNotificationManager.activeNotifications
if(notifications.isNotEmpty())
{
//you don't have notifications
}
else
{
//you have notifications
}
An alternative to the deleteIntent is the following which has proved beneficial in my own app:
Basically, you create an intent with your notification that starts an IntentService (or any other service) and in onHandleIntent you can set a flag indicating whether the notification is active.
You can set this intent to be fired when the user taps the notification (contentIntent) and/or when the user clears it from the list (deleteIntent).
To illustrate it, here is what I do in my own app. When building the notification I set
Intent intent = new Intent(this, CleanupIntentService.class);
Notification n = NotificationCompat.Builder(context).setContentIntent(
PendingIntent.getActivity(this, 0, intent, 0)).build();
When the notification is tapped, my CleanupIntentService is launched, setting a flag (in the service that created the notification):
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
super.onCreate(); // If removed, onHandleIntent is not called
return super.onStartCommand(intent, flags, startId);
}
@Override
protected void onHandleIntent(Intent intent) {
OtherService.setNotificationFlag(false);
}
In my situation, I wanted to check if a Notification was already shown before showing another. And it turns out there's a simple way to do it without listening to when the Notification was deleted or dismissed with .setAutoCancel(true) on NotificationManagerCompat.Builder.
private val NOTIF_ID = 80085
private val CHANNEL_ID = "com.package.name.ClassName.WhatNotifycationDoes"
private lateinit var mNotificationManagerCompat: NotificationManagerCompat
private lateinit var mNotificationManager: NotificationManager // this is for creating Notification Channel in newer APIs
override fun onCreate() {
super.onCreate()
mNotificationManagerCompat = NotificationManagerCompat.from(this)
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
mNotificationManager = getSystemService(NotificationManager::class.java)
showNotification()
startWatching()
}
private fun showNotification() {
val contentIntent = Intent(this, MainActivity::class.java)
.apply { flags = Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK }
val contentPendingIntent = PendingIntent.getActivity(this, 1, contentIntent, 0)
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
val name = getString(R.string.app_name)
val importance = NotificationManager.IMPORTANCE_HIGH
val channel = NotificationChannel(CHANNEL_ID, name, importance)
channel.description = getString(R.string.your_custom_description)
mNotificationManager.createNotificationChannel(channel)
}
val mNewStatusNotificationBuilder = NotificationCompat.from(this)
mNewStatusNotificationBuilder = NotificationCompat.Builder(this, CHANNEL_ID)
.setContentTitle(getString(R.string.app_name))
.setContentText(getString(R.string.simple_text))
.setPriority(NotificationCompat.PRIORITY_DEFAULT)
.setContentIntent(contentPendingIntent)
.setAutoCancel(true) // This dismisses the Notification when it is clicked
.setOnlyAlertOnce(true) //this is very important, it pops up the notification only once. Subsequent notify updates are muted. unless it is loaded again
if (Build.VERSION.SDK_INT > Build.VERSION_CODES.LOLLIPOP)
mNewStatusNotificationBuilder.setSmallIcon(R.drawable.ic_notification)
notification = mNewStatusNotificationBuilder.build()
mNotificationManagerCompat.notify(NOTIF_ID, notification)
}
