How do I access BuildContext outside of a stateful or stateless widget? - flutter

Question

I created a class that extends the AppBar class in Flutter so I can reuse it whenever I need it.
My problem is how do I access the Stateful/Stateless widget build context?
class AppBarLayout extends AppBar {
static final AppController _appController = new AppController();
final GlobalKey<ScaffoldState> _scaffoldKey;
final String appBarTitle;
AppBarLayout(this.appBarTitle,this._scaffoldKey): super(
title: Text(appBarTitle),
leading: IconButton(
onPressed: () => _scaffoldKey.currentState.openDrawer(),
iconSize: 28,
icon: Icon(Icons.menu,color: Colors.white),
),
actions: <Widget>[
IconButton(
onPressed: () => _appController.signOut().then((_) {
_appController.navigateTo(context, new GoogleSignView());
}),
icon: Icon(Icons.account_box),
padding: EdgeInsets.all(0.0),
),
],
);
}

Answer 1

You would need to wrap your Scaffold in a Staless or Stateful widget, so you can get the context, e.g.
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
#override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
int _counter = 0;
void _incrementCounter() {
setState(() {
_counter++;
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBarLayout(GlobalKey(debugLabel: 'someLabel'), appBarTitle: 'The Title', context: context,),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text(
'You have pushed the button this many times:',
),
Text(
'$_counter',
style: Theme.of(context).textTheme.display1,
),
],
),
),
floatingActionButton: FloatingActionButton(
onPressed: _incrementCounter,
tooltip: 'Increment',
child: Icon(Icons.add),
),
);
}
}
class AppBarLayout extends AppBar {
final GlobalKey<ScaffoldState> _scaffoldKey;
final String appBarTitle;
final BuildContext context;
AppBarLayout(this._scaffoldKey, {this.appBarTitle, this.context}): super(
title: Text(appBarTitle),
leading: IconButton(
onPressed: () => _scaffoldKey.currentState.openDrawer(),
iconSize: 28,
icon: Icon(Icons.menu,color: Colors.white),
),
actions: <Widget>[
IconButton(
onPressed: () {
print('Button pressed');
},
icon: Icon(Icons.account_box),
padding: EdgeInsets.all(0.0),
),
],
);
}
Here I'm using a very similar Widget of what you have.