How to send notification to all Onesignal users with Flutter

Question

Hello!

I’m learning notifications with flutter and oneSignal. I figured out how to send notifications to specific users, but I don’t know how to send them to multiple users. My code so far is this:

OneSignal.shared.postNotification(OSCreateNotification(
          playerIds: ['e2926936-48d7-46c7-a093-169c19b902ee'],
          content: 'Mensagem de teste',
          heading: 'Acho que esta funcionando'));

In the playerIds is where you put users to send. He expects a list, but searching the internet I saw that to send to all users just leave playerIds empty. I tried this way and could not. I tried these ways: playerIds: []; playerIds: null; playerIds: [''];, I also tried to delete the line, but from the exception all attempts

Anyway, I need you to send notification to all users at once

Answer 1

In the documentation of the method postNotification says that:

Please note that you must specify at least one Onesignal user ID that the notification should be sent to, using the playerIds Property.

(Free translation: Please note that you need to specify at least one user ID that the notification should be sent using the property playerIds)

That is, there is no such possibility of leaving blank or null to send to everyone. Where did you read this?

The other method postNotificationWithJsonalso expects a list of PlayerIds.

To send a notification to all users, use the Onesignal Dashboard as instructed here:

• Click on the tab Messages
• Choose as audience "Subscribed Users" (Which if you haven’t changed represents all subscribed devices)
• Enter the title, subtitle, message, image and other settings of your notification.
• Choose other settings like scheduling, extra fields for deep-linking or priority.
• Press the button "Send"

For a better description of the features see official documentation