Here is the complete example in answer to the first question above. The code is modified from the above. Note the passing of the callback method to Page 3 constructor.
import 'package:flutter/material.dart';
void main() {
runApp(const MyApp());
}
const String page1 = "Home";
const String page2 = "Service";
const String page3 = "Profile";
const String title = "BNB Demo";
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
@override
Widget build(BuildContext context) {
return const MaterialApp(
title: title,
home: MyHomePage(title: title),
);
}
}
class MyHomePage extends StatefulWidget {
const MyHomePage({Key? key, required this.title}) : super(key: key);
final String title;
@override
State<MyHomePage> createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
late List<Widget> _pages;
late Widget _page1;
late Widget _page2;
late Widget _page3;
late int _currentIndex;
late Widget _currentPage;
@override
void initState() {
super.initState();
_page1 = const Page1();
_page2 = const Page2();
_page3 = Page3(changePage: _changeTab);
_pages = [_page1, _page2, _page3];
_currentIndex = 0;
_currentPage = _page1;
}
void _changeTab(int index) {
setState(() {
_currentIndex = index;
_currentPage = _pages[index];
});
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: _currentPage,
bottomNavigationBar: BottomNavigationBar(
onTap: (index) {
_changeTab(index);
},
currentIndex: _currentIndex,
items: const [
BottomNavigationBarItem(
label: page1,
icon: Icon(Icons.home),
),
BottomNavigationBarItem(
label: page2,
icon: Icon(Icons.home_repair_service),
),
BottomNavigationBarItem(
label: page3,
icon: Icon(Icons.person),
),
]),
drawer: Drawer(
child: Container(
margin: const EdgeInsets.only(top: 20.0),
child: Column(
children: <Widget>[
_navigationItemListTitle(page1, 0),
_navigationItemListTitle(page2, 1),
_navigationItemListTitle(page3, 2),
],
),
),
),
);
}
Widget _navigationItemListTitle(String title, int index) {
return ListTile(
title: Text(
'$title Page',
style: TextStyle(color: Colors.blue[400], fontSize: 22.0),
),
onTap: () {
Navigator.pop(context);
_changeTab(index);
},
);
}
}
class Page1 extends StatelessWidget {
const Page1({Key? key}) : super(key: key);
@override
Widget build(BuildContext context) {
return Center(
child: Text('$page1 Page', style: Theme.of(context).textTheme.headline6),
);
}
}
class Page2 extends StatelessWidget {
const Page2({Key? key}) : super(key: key);
@override
Widget build(BuildContext context) {
return Center(
child: Text('$page2 Page', style: Theme.of(context).textTheme.headline6),
);
}
}
class Page3 extends StatelessWidget {
const Page3({Key? key, required this.changePage}) : super(key: key);
final void Function(int) changePage;
@override
Widget build(BuildContext context) {
return Align(
alignment: Alignment.center,
child: Column(
mainAxisSize: MainAxisSize.min,
children: [
Text('$page3 Page', style: Theme.of(context).textTheme.headline6),
ElevatedButton(
onPressed: () => changePage(0),
child: const Text('Switch to Home Page'),
)
],
),
);
}
}
