Flutter how to pass value to State class - flutter

Question

I having trouble with passing parameter between classes. When i wanted to pass email from MyScreen classes to my TabScreen it shows:
A [State] object's configuration is the corresponding [StatefulWidget] instance. This property is initialized by the framework before calling [initState]. If the parent updates this location in the tree to a new widget with the same [runtimeType] and [Widget.key] as the current configuration, the framework will update this property to refer to the new widget and then call [didUpdateWidget], passing the old configuration as an argument.
Not sure how to handle this passing variables to a state class. I can use '${widget.email}' but only in widget array. Inside List tabs, I really have no idea how. Quite new to flutter way of doing things...am i doing it wrongs somewhere?
import 'package:flutter/material.dart';
import 'package:my_helper/tab_screen2.dart';
import 'package:my_helper/tab_screen3.dart';
import 'tab_screen.dart';
class MainScreen extends StatefulWidget {
final String email; //<-managed to get this variable from previous screen
MainScreen({Key key,this.email}) : super(key: key);
#override
_MainScreenState createState() => _MainScreenState();
}
class _MainScreenState extends State<MainScreen> {
int currentTabIndex = 0;
List<Widget> tabs = [
TabScreen("Home", widget.email), //<- ERROR this widget.email shows error "only static member can be ...."
TabScreen2("Message"),
TabScreen3("Profile")
];
String $pagetitle = "Home";
onTapped(int index) {
setState(() {
currentTabIndex = index;
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text($pagetitle),
),
body: tabs[currentTabIndex],
bottomNavigationBar: BottomNavigationBar(
onTap: onTapped,
currentIndex: currentTabIndex,
items: [
BottomNavigationBarItem(
icon: Icon(Icons.search),
title: Text("Jobs"),
),
BottomNavigationBarItem(
icon: Icon(Icons.mail),
title: Text("Messages"),
),
BottomNavigationBarItem(
icon: Icon(Icons.person),
title: Text("Profile"),
)
],
),
);
}
}
my TabScreen
import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;
class TabScreen extends StatelessWidget {
final String apptitle,email;
TabScreen(this.apptitle,this.email);
#override
Widget build(BuildContext context) {
return Column(
children: <Widget>[
Text(email)
],
);
}
}

Answer 1

You need to initialize tabs in the initState() method. Change your _MainScreenState class to match this:
class _MainScreenState extends State<MainScreen> {
int currentTabIndex = 0;
List<Widget> tabs;
String $pagetitle = "Home";
onTapped(int index) {
setState(() {
currentTabIndex = index;
});
}
#override
void initState() {
super.initState();
tabs = [
TabScreen("Home", widget.email),
TabScreen2("Message"),
TabScreen3("Profile"),
];
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text($pagetitle),
),
body: tabs[currentTabIndex],
bottomNavigationBar: BottomNavigationBar(
onTap: onTapped,
currentIndex: currentTabIndex,
items: [
BottomNavigationBarItem(
icon: Icon(Icons.search),
title: Text("Jobs"),
),
BottomNavigationBarItem(
icon: Icon(Icons.mail),
title: Text("Messages"),
),
BottomNavigationBarItem(
icon: Icon(Icons.person),
title: Text("Profile"),
)
],
),
);
}
}