title: Flutter equivalent to Swift's NotificationCenter?
body: <p>I'm using FirebaseMessaging to send push notifications to my Flutter app. Those notifications contain chat details. </p>
  
  <p>If the app is currently active and the user is at the chat page, the page should be updated to show the new message (this I can handle).</p>
  
  <p>If the app is on any other page, a local notification/toast should be shown.</p>
  
  <p>My problem, how do I forward the notification to the chat page?</p>
  
  <p>I have FirebaseMessaging listening on the root page. And I can use <code>ModalRoute.of(context).isCurrent</code> to determine if the root page is the current page when the notification comes in. How can I broadcast the notification to the chat page when it is the active page?</p>
  
  <p>In Swift, I'd use NotificationCenter to send data from the app delegate and the chat page would listen for it. I'm hoping something similar is available for Flutter.</p>