custom_will_pop_scope 2.1.1
custom_will_pop_scope: ^2.1.1 copied to clipboard
Enables 'onWillPop' callbacks on Cupertino page transitions and improves visual feedback of rejected "Swipe to go back" gestures.
import 'package:custom_will_pop_scope/custom_will_pop_scope.dart';
import 'package:example/locator.dart';
import 'package:example/navigation_service.dart';
import 'package:example/router.dart' as router;
import 'package:example/router.dart';
import 'package:flutter/material.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
final theme = ThemeData(
primarySwatch: Colors.blue,
);
@override
Widget build(BuildContext context) {
setupLocator();
return MaterialApp(
theme: theme,
home: HomeScreen(),
initialRoute: router.homeScreen,
onGenerateRoute: router.generateRoute,
navigatorKey: locator<NavigationService>().navigationKey,
);
}
}
class HomeScreen extends StatelessWidget {
void navigateToNext() {
locator<NavigationService>().navigateTo(secondScreen);
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: Text('CustomWillPopScope Demo')),
body: Center(
child: ElevatedButton(
child: Padding(
padding: EdgeInsets.symmetric(horizontal: 24.0, vertical: 12.0),
child: Text('Go to second screen'),
),
onPressed: () => navigateToNext(),
),
),
);
}
}
class SecondScreen extends StatefulWidget {
@override
_SecondScreenState createState() => _SecondScreenState();
}
class _SecondScreenState extends State<SecondScreen> {
final Color _color = Colors.pink;
final NavigationService _navigationService = locator<NavigationService>();
/// Holds the state of the screen.
bool _canReturn = true;
/// Shows an alert and returns `false` when `_canReturn` is `true`.
/// This prevents the navigator from popping this route.
Future<bool> _onWillPop() async {
if (!_canReturn) {
// // Show an alert before returning `false`.
showDialog(
context: context,
builder: (context) => AlertDialog(
content: Text('Back navigation is disabled.'),
),
);
// Return `false` to prevent the route from popping.
return false;
} else {
_navigationService.removeLastRouteName();
return true;
}
}
void _onPopAction() {
_navigationService.removeLastRouteName();
}
/// Updates `_canReturn` with the provided value.
void _updateChanges(bool value) => setState(() => _canReturn = value);
@override
Widget build(BuildContext context) {
return CustomWillPopScope(
// canReturn is optional, it is set to true by default
canReturn: _canReturn,
onWillPop: _onWillPop,
// onPopAction is optional, use it when you have a function to call when dissmissing the enclosing [ModalRoute].
onPopAction: _onPopAction,
child: Scaffold(
appBar: AppBar(title: Text('Second Screen'), backgroundColor: _color),
body: Column(
children: [
Container(
child: SwitchListTile(
activeColor: _color,
onChanged: _updateChanges,
title: Text('Enable back navigation'),
value: _canReturn,
),
decoration: BoxDecoration(
border: Border.all(color: _color),
borderRadius: BorderRadius.circular(6.0),
),
margin: EdgeInsets.symmetric(horizontal: 12.0),
),
Expanded(
child: PageView(
children: [
Scaffold(
body: Center(
child: Text("Page 1"),
),
),
Scaffold(
body: Center(
child: Text("Page 2"),
),
),
Scaffold(
body: Center(
child: Text("Page 3"),
),
),
],
),
),
],
),
),
);
}
}