How to call function/method when we receive an FCM notification on IOS (Foreground)?

[MrunalrajRedij]

Does anybody know how to trigger a function/method when we receive an FCM notification on IOS (Foreground)?
For Android it's simple, there is a callback

    FirebaseMessaging.onMessage.listen((remoteMessage) {
       //code here....
    });

but this callback doesn't execute for IOS.
I believe IOS takes care of showing FCM notification itself when on the foreground. So how can I do something, when I get FCM notification on IOS (foreground)