原生Android Activity启动二级路由后，如何让Flutter模块返回原生Android Activity？

Question

I'm adding flutter to a existing Android project and everything is working fine, except one thing:

My Android project has only one Flutter module. In that Flutter module I have two routes that will be shown in different parts of the Android project:

  initialRoute: '/',
  routes: {
    '/': (_) => MyHomePage(),
    '/settings': (_) => _SettingsPage()
  }

In the Android Activity if I start a new Flutter activity with this:

startActivity(
            FlutterActivity
                .withCachedEngine(flutterEngineId)
                .build(this)
        )

It will start Flutter with the default page route ( / ) which is the expected result. Then in this Flutter page if I navigate back, it will pop the Flutter engine and navigate back to the Android Activity. Everything good for now.

But if I start a Flutter activity with a custom initial route, and then I press the back button, it will not pop the Flutter engine and navigate to the Android activity but to the initial Flutter route (in this case the / route).

    startActivity(
        FlutterActivity
            .withNewEngine()
            .initialRoute("/settings")
            .build(this)
    )

Why we're having this behavior if we are specifying the initial route while starting the FlutterActivity ?

And if this is the expect behavior, then what is the best way of make it navigate to the Android activity?

Answer 1

I'm adding flutter to a existing Android project and everything is working fine, except one thing:

My Andrid project have only one Flutter module in that Flutter module I have two routes that will be shown in different parts of the Android project:

  initialRoute: '/',
  routes: {
    '/': (_) => MyHomePage(),
    '/settings': (_) => _SettingsPage()
  }

In the Android Activity if I start a new Flutter activity with this:

startActivity(
            FlutterActivity
                .withCachedEngine(flutterEngineId)
                .build(this)
        )

It will start Flutter with the default page route ( / ) wich is the expected result. Then in this Flutter page if I navigate back, it will pop the Flutter engine and navigate back to the Android Activity. Everything good for now.

But if I start a Flutter activity with a custom initial route, and then I press the back button, it will not pop the Flutter engine and navigate to the Android activity but to the initial Flutter route (in this case the / route).

    startActivity(
        FlutterActivity
            .withNewEngine()
            .initialRoute("/settings")
            .build(this)
    )

Why we're having this behaviour if we are specifying the initial route while starting the FlutterActivity ?

And if this is the expect behaviour, then what is the best way of make it navigate to the Android activity?

Answer 2

Try SystemNavigator.pop() to pop the topmost flutter route

More details at https://api.flutter.dev/flutter/services/SystemNavigator/pop.html