How to keep AppBar and back arrow stationary when navigating to a new screen - flutter

Question

I want to have the top half of by screen appear static when navigating between pages in Flutter.
To try to make this happen I put use the Hero widget and use it on a column that contains an AppBar and some other content that I want to appear static when pushing a new page.
The App Bar itself remains static but the back arrow disappears when the animation starts and reappears when the animation is done.
How can I have the back arrow remain visible the entire time while the rest of the page is animating into place?
class FirstScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
body: Column(
children: [
Hero(
tag: 'top',
child: Column(
children: <Widget>[
AppBar(
title: Text('First'),
backgroundColor: Color.fromARGB(255, 50, 64, 182),
),
Container(
height: 80.0,
)
],
),
),
RaisedButton(
child: Text('Next'),
onPressed: () {
Navigator.pushNamed(context, '/second');
},
),
],
),
);
}
}
class SecondScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
body: Column(
children: [
Hero(
tag: 'top',
child: Column(
children: <Widget>[
AppBar(
title: Text('Second'),
),
Container(
height: 80.0,
// color: Colors.green,
),
],
),
),
RaisedButton(
child: Text('Back'),
onPressed: () {
Navigator.pop(context);
},
),
],
),
);
}
}

Answer 1

Things weren't quite set up right in your code. It should go Scaffold/Hero/your content. I've also used this simple fading page route when performing the navigation:
class HomePage extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('First'),
leading: Icon(null),
backgroundColor: Color.fromARGB(255, 50, 64, 182)),
body: Hero(
tag: 'top',
child: Column(
children: <Widget>[
Container(height: 80.0),
RaisedButton(
child: Text('Next'),
onPressed: () {
Navigator.push(context, MyCustomRoute(builder: (context) {
return SecondScreen();
}));
},
),
],
),
),
);
}
}
class SecondScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Second'),
leading: IconButton(icon: Icon(Icons.arrow_back), onPressed: () {
Navigator.pop(context);
},),
backgroundColor: Color.fromARGB(255, 50, 64, 182)),
body: Hero(
tag: 'top',
child: Column(
children: <Widget>[
Container(height: 80.0),
RaisedButton(
child: Text('Back'),
onPressed: () {
Navigator.pop(context);
},
),
],
),
),
);
}
}
class MyCustomRoute<T> extends MaterialPageRoute<T> {
MyCustomRoute({ WidgetBuilder builder, RouteSettings settings })
: super(builder: builder, settings: settings);
#override
Widget buildTransitions(BuildContext context,
Animation<double> animation,
Animation<double> secondaryAnimation,
Widget child) {
if (settings.isInitialRoute)
return child;
// Fades between routes. (If you don't want any animation,
// just return child.)
return new FadeTransition(opacity: animation, child: child);
}
}

Answer 2

You could do automaticallyImplyLeading: false and then do
leading: IconButton(
icon: Icon(Icons.arrow_back),
onPressed: () => Navigator.of(context).pop(),
),

Answer 3

I have it done this way, by adding automaticallyImplyLeading: true,
Hope this solves your problem!
appBar: AppBar(
automaticallyImplyLeading: true,
),