I made a changeable theme in flutter and later I made multi-language support, I used getx for theme switching, I used easy_localization for language change. When I use GetMeterialapp on the main page, it doesn't work, when I do Meterialapp it works multi-language, but the theme change does not work. import 'package:get/get.dart' on another page; i am using and when i use easy_localization here easy_localization is not working. I'm canceling getx is working. I couldn't get out of this situation. If I can't solve it, I will either give up without changing the theme or multi-language support.
await EasyLocalization.ensureInitialized();
runApp(EasyLocalization(supportedLocales: [
Locale("en", "US"),
Locale("tr", "TR"),
], path: "assets/Language", saveLocale: true, child: MyApp()));
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return new MaterialApp(
title: 'Home Page',
localizationsDelegates: context.localizationDelegates,
supportedLocales: context.supportedLocales,
locale: context.locale,
theme: Themes.light,
darkTheme: Themes.dark,
themeMode: ThemeService().theme,
home: MyHomePage(),
debugShowCheckedModeBanner: false,
);
}
}
Initialize GetStorage inside main method.
void main() async{
WidgetsFlutterBinding.ensureInitialized();
await GetStorage.init();
runApp(MyApp());
}
Create storage object.
final storage = GetStorage();
Set a default value if storage is null.
storage.writeIfNull('darkmode', false);
Read the theme mode value.
bool isDarkMode = storage.read('darkmode');
Apply the theme mode.
Switch(
value: isDarkMode ,
onChanged: (value) => storage.write('darkmode', value),
)
Full code:
import 'package:flutter/material.dart';
import 'package:get_storage/get_storage.dart';
import 'package:get/get.dart';
void main() async{
WidgetsFlutterBinding.ensureInitialized();
await GetStorage.init();
runApp(MyApp());
}
class MyApp extends StatelessWidget {
final storage = GetStorage();
#override
Widget build(BuildContext context) {
appdata.writeIfNull('darkmode', false);
return SimpleBuilder(
builder: (_)
{
bool isDarkMode = storage.read('darkmode');
return GetMaterialApp(
theme: isDarkMode ? ThemeData.dark() : ThemeData.light(),
home: Scaffold(
appBar: AppBar(title: Text("Getx Dynamic theme change"),),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Image.asset(isDarkMode ? 'images/night.png' :'images/day.png' ,width: 100,height: 100,),
Switch(
value: isDarkMode ,
onChanged: (value) => storage.write('darkmode', value),
)
],
),
),
),
);
},
);
}
}
I'm trying to start a new screen within an onTap but I get the following error:
Navigator operation requested with a context that does not include a
Navigator.
The code I am using to navigate is:
onTap: () { Navigator.of(context).pushNamed('/settings'); },
I have set up a route in my app as follows:
routes: <String, WidgetBuilder>{
'/settings': (BuildContext context) => new SettingsPage(),
},
I've tried to copy the code using the stocks sample application. I've looked at the Navigator and Route documentation and can't figure out how the context can be made to include a Navigator. The context being used in the onTap is referenced from the parameter passed into the build method:
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
SettingsPage is a class as follows:
class SettingsPage extends Navigator {
Widget buildAppBar(BuildContext context) {
return new AppBar(
title: const Text('Settings')
);
}
#override
Widget build(BuildContext context) {
return new Scaffold(
appBar: buildAppBar(context),
);
}
}
TLDR: Wrap the widget which needs to access to Navigator into a Builder or extract that sub-tree into a class. And use the new BuildContext to access Navigator.
This error is unrelated to the destination. It happens because you used a context that doesn't contain a Navigator instance as parent.
How do I create a Navigator instance then ?
This is usually done by inserting in your widget tree a MaterialApp or WidgetsApp. Although you can do it manually by using Navigator directly but less recommended. Then, all children of such widget can access NavigatorState using Navigator.of(context).
Wait, I already have a MaterialApp/WidgetsApp !
That's most likely the case. But this error can still happens when you use a context that is a parent of MaterialApp/WidgetsApp.
This happens because when you do Navigator.of(context), it will start from the widget associated to the context used. And then go upward in the widget tree until it either find a Navigator or there's no more widget.
In the first case, everything is fine. In the second, it throws a
Navigator operation requested with a context that does not include a Navigator.
So, how do I fix it ?
First, let's reproduce this error :
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Center(
child: RaisedButton(
child: Text("Foo"),
onPressed: () => Navigator.pushNamed(context, "/"),
),
),
);
}
}
This example creates a button that attempts to go to '/' on click but will instead throw an exception.
Notice here that in the
onPressed: () => Navigator.pushNamed(context, "/"),
we used context passed by to build of MyApp.
The problem is, MyApp is actually a parent of MaterialApp. As it's the widget who instantiate MaterialApp! Therefore MyApp's BuildContext doesn't have a MaterialApp as parent!
To solve this problem, we need to use a different context.
In this situation, the easiest solution is to introduce a new widget as child of MaterialApp. And then use that widget's context to do the Navigator call.
There are a few ways to achieve this. You can extract home into a custom class :
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
home: MyHome()
);
}
}
class MyHome extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Center(
child: RaisedButton(
child: Text("Foo"),
onPressed: () => Navigator.pushNamed(context, "/"),
),
);
}
}
Or you can use Builder :
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Builder(
builder: (context) => Center(
child: RaisedButton(
child: Text("Foo"),
onPressed: () => Navigator.pushNamed(context, "/"),
),
),
),
);
}
}
Hy guys, i have the same problem. This is occur for me. The solution what i found is very simple. Only what i did is in a simple code:
void main() {
runApp(MaterialApp(
home: YOURAPP() ,
),
);
}
I hope was useful.
Make sure your current parent widget not with same level with MaterialApp
Wrong Way
class HomeScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
appBar: AppBar(
centerTitle: true,
title: Text('Title'),
),
body: Center(
child: Padding(
padding: EdgeInsets.symmetric(vertical: 8.0, horizontal: 16.0),
child: RaisedButton(
onPressed: () {
//wrong way: use context in same level tree with MaterialApp
Navigator.push(context,
MaterialPageRoute(builder: (context) => ScanScreen()));
},
child: const Text('SCAN')),
)),
),
);
}
}
Right way
void main() => runApp(MaterialApp(
title: "App",
home: HomeScreen(),
));
class HomeScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
centerTitle: true,
title: Text('Title'),
),
body: Center(
child: Padding(
padding: EdgeInsets.symmetric(vertical: 8.0, horizontal: 16.0),
child: RaisedButton(
onPressed: () {
//right way: use context in below level tree with MaterialApp
Navigator.push(context,
MaterialPageRoute(builder: (context) => ScanScreen()));
},
child: const Text('SCAN')),
)),
);
}
}
Just like with a Scaffold you can use a GlobalKey. It doesn't need context.
final _navKey = GlobalKey<NavigatorState>();
void _navigateToLogin() {
_navKey.currentState.popUntil((r) => r.isFirst);
_navKey.currentState.pushReplacementNamed(LoginRoute.name);
}
#override
Widget build(BuildContext context) {
return MaterialApp(
navigatorKey: _navKey,
...
);
}
I set up this simple example for routing in a flutter app:
import 'package:flutter/material.dart';
void main() {
runApp(new MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return new MaterialApp(
title: 'Flutter Demo',
home: new MyHomePage(),
routes: <String, WidgetBuilder>{
'/settings': (BuildContext context) => new SettingsPage(),
},
);
}
}
class MyHomePage extends StatelessWidget {
#override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(
title: new Text('TestProject'),
),
body: new Center(
child: new FlatButton(
child: const Text('Go to Settings'),
onPressed: () => Navigator.of(context).pushNamed('/settings')
)
)
);
}
}
class SettingsPage extends StatelessWidget {
#override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(
title: new Text('SettingsPage'),
),
body: new Center(
child: new Text('Settings')
)
);
}
}
Note, that the SettingsPage extends StatelessWidget and not Navigator. I'm not able to reproduce your error.
Does this example help you in building your app? Let me know if I can help you with anything else.
You should rewrite your code in main.dart
FROM:
void main() => runApp(MyApp());
TO
void main() {
runApp(MaterialApp(
title: 'Your title',
home: MyApp(),));}
The point is to have the home property to be your first page
this worked for me, I hope it will help someone in the future
A complete and tested solution:
import 'dart:async';
import 'package:flutter/material.dart';
import 'package:my-app/view/main-view.dart';
class SplashView extends StatelessWidget {
#override
Widget build(BuildContext context) {
return new MaterialApp(
home: Builder(
builder: (context) => new _SplashContent(),
),
routes: <String, WidgetBuilder>{
'/main': (BuildContext context) => new MainView()}
);
}
}
class _SplashContent extends StatefulWidget{
#override
_SplashContentState createState() => new _SplashContentState();
}
class _SplashContentState extends State<_SplashContent>
with SingleTickerProviderStateMixin {
var _iconAnimationController;
var _iconAnimation;
startTimeout() async {
var duration = const Duration(seconds: 3);
return new Timer(duration, handleTimeout);
}
void handleTimeout() {
Navigator.pushReplacementNamed(context, "/main");
}
#override
void initState() {
super.initState();
_iconAnimationController = new AnimationController(
vsync: this, duration: new Duration(milliseconds: 2000));
_iconAnimation = new CurvedAnimation(
parent: _iconAnimationController, curve: Curves.easeIn);
_iconAnimation.addListener(() => this.setState(() {}));
_iconAnimationController.forward();
startTimeout();
}
#override
Widget build(BuildContext context) {
return new Center(
child: new Image(
image: new AssetImage("images/logo.png"),
width: _iconAnimation.value * 100,
height: _iconAnimation.value * 100,
)
);
}
}
As per this comment If your navigator is inside Material context navigator push will give this error. if you create a new widget and assign it to the material app home navigator will work.
This won't work
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return new MaterialApp(
home: new Scaffold(
appBar: new AppBar(
title: new Text("Title"),
),
body: new Center(child: new Text("Click Me")),
floatingActionButton: new FloatingActionButton(
child: new Icon(Icons.add),
backgroundColor: Colors.orange,
onPressed: () {
print("Clicked");
Navigator.push(
context,
new MaterialPageRoute(builder: (context) => new AddTaskScreen()),
);
},
),
),
);
}
}
This will work
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return new MaterialApp(
home: new HomeScreen());
}
}
class HomeScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(
title: new Text("Title"),
),
body: new Center(child: new Text("Click Me")),
floatingActionButton: new FloatingActionButton(
child: new Icon(Icons.add),
backgroundColor: Colors.orange,
onPressed: () {
print("Clicked");
Navigator.push(
context,
new MaterialPageRoute(builder: (context) => new AddTaskScreen()),
);
},
),
);
}
}
I was facing the same problem and solved by removing home from MaterialApp and use initialRoute instead.
return MaterialApp(
debugShowCheckedModeBanner: false,
initialRoute: '/',
routes: {
'/': (context) => MyApp(),
'/settings': (context) => SettingsPage(),
},
);
And
onTap: () => {
Navigator.pushNamed(context, "/settings")
},
It is Simple
instead using this normal code
`runApp(BasicBankingSystem());`
wrap it with MaterialApp
runApp(MaterialApp(home: BasicBankingSystem()));
It happens because the context on the widget that tries to navigate is still using the material widget.
The short answer for the solution is to :
extract your widget
that has navigation to new class so it has a different context when calling the navigation
When your screen is not navigated from other screen,you don't initially have access to the navigator,Because it is not instantiated yet.So in that case wrap your widget with builder and extract context from there.This worked for me.
builder: (context) => Center(
child: RaisedButton(
child: Text("Foo"),
onPressed: () => Navigator.pushNamed(context, "/"),
),
You ca use this plugin
https://pub.dev/packages/get/versions/2.0.2
in The MaterialApp assign property navigatorKey: Get.key,
MaterialApp(
navigatorKey: Get.key,
initialRoute: "/",
);
you can access Get.toNamed("Your route name");
Change your main function example:
void main() {
runApp(
MaterialApp(
title: 'Your title',
home: MyApp(),
)
);
}
use this
void main() {
runApp(MaterialApp(debugShowCheckedModeBanner: false, home: MyApp()),);
}
instead of this
void main() {runApp(MyApp());}
Wrap with materialapp
reproduce code
import 'dart:convert';
import 'package:flutter/material.dart';
void main() {
// reproduce code
runApp(MyApp());
// working switch //
// runApp(
//
// MaterialApp(debugShowCheckedModeBanner: false, home: MyApp()),);
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
home: Scaffold(
body:
Column(mainAxisAlignment: MainAxisAlignment.center, children: [
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Container(
height: 100,
width: 100,
child: ElevatedButton(
onPressed: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => IntroPage(Isscar4: true)),
);
},
child: RichText(
text: TextSpan(
text: 'CAR',
style: TextStyle(
letterSpacing: 3,
color: Colors.white,
fontWeight: FontWeight.w400),
children: [
TextSpan(
text: '4',
style: TextStyle(
fontSize: 25,
color: Colors.red,
fontWeight: FontWeight.bold))
],
)),
),
),
],
),
SizedBox(
height: 10,
),
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Container(
height: 100,
width: 100,
child: ElevatedButton(
onPressed: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => IntroPage(Isscar4: false)),
);
},
child: RichText(
text: TextSpan(
text: 'BIKE',
style: TextStyle(
letterSpacing: 3,
color: Colors.white,
fontWeight: FontWeight.w400),
children: [
TextSpan(
text: '2',
style: TextStyle(
fontSize: 25,
color: Colors.red,
fontWeight: FontWeight.bold))
],
)),
),
),
],
)
])));
}
MaterialApp Swithwidget(istrue) {
return MaterialApp(
home: Scaffold(
body: IntroPage(
Isscar4: istrue,
),
),
);
}
}
class Hi extends StatelessWidget {
const Hi({Key? key}) : super(key: key);
#override
Widget build(BuildContext context) {
return Container(
child: Text("df"),
);
}
}
class IntroPage extends StatelessWidget {
final Isscar4;
IntroPage({
Key? key,
required this.Isscar4,
}) : super(key: key);
List<Widget> listPagesViewModel = [];
List<IntroModel> models = [];
#override
Widget build(BuildContext context) {
List<dynamic> intro = fetchIntroApi(Isscar4);
intro.forEach((element) {
var element2 = element as Map<String, dynamic>;
var cd = IntroModel.fromJson(element2);
models.add(cd);
});
models.forEach((element) {
listPagesViewModel.add(Text(""));
});
return MaterialApp(
debugShowCheckedModeBanner: false,
home: Scaffold(
body: Container(),
));
}
List fetchIntroApi(bool bool) {
var four = bool;
if (four) {
var data =
'[ {"name_Title": "title name1","description": "description1"}, {"name_Title": "title name2","description": "description2"}, {"name_Title": "title name3","description": "description3"}, {"name_Title": "title name4","description": "description4"} ]';
return json.decode(data);
} else {
var data =
'[ {"name_Title": "title name","description": "description1"}, {"name_Title": "title name2","description": "description2"}, {"name_Title": "title name3","description": "description3"} ]';
return json.decode(data);
}
}
}
class IntroModel {
String? nameTitle;
String? description;
IntroModel({this.nameTitle, this.description});
IntroModel.fromJson(Map<String, dynamic> json) {
nameTitle = json['name_Title'];
description = json['description'];
}
Map<String, dynamic> toJson() {
final Map<String, dynamic> data = new Map<String, dynamic>();
data['name_Title'] = this.nameTitle;
data['description'] = this.description;
return data;
}
}
class Splash extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Splash Screen',
theme: ThemeData(
primarySwatch: Colors.green,
),
home: MyState(),
debugShowCheckedModeBanner: false,
);
}
void main() {
runApp(Splash());
}
class MyState extends StatefulWidget{
#override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyState> {
#override
void initState() {
super.initState();
Timer(Duration(seconds: 3),
()=>Navigator.pushReplacement(context,
MaterialPageRoute(builder:
(context) =>
Login()
)
)
);
}
#override
Widget build(BuildContext context) {
return Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center ,
children: [
Container(
child:
Image.asset("assets/images/herosplash.png"),
),
],
),
);
}
}
Builder(
builder: (context) {
return TextButton(
child: const Text('Bearbeiten'),
onPressed:(){
Navigator.push(
context,
MaterialPageRoute(builder: (context) => const gotothesiteyouwant()),
);
});
}
),
Here, all you need is to make MaterialApp the parent of your Build. This is because the context that you've used to navigate to a different screen is finding a MaterialApp or a WidgetApp as a parent of the build.
And Since in your case, the situation is the opposite, therefore you need to modify it by either calling a new Stateless widget the parent of is the MaterialApp or by simply using a Builder as home: Builder in MaterialApp.
Hope this would help!
Did anyone successfully implemented WebSocket using json_rpc_2 package?https://pub.dartlang.org/packages/json_rpc_2
I try to present live data, e.g. a ticker, from this API: https://api.hitbtc.com/
Actually, I managed to solve the problem. Here's the code:
import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:json_rpc_2/json_rpc_2.dart' as json_rpc;
import 'package:web_socket_channel/io.dart';
class SymbolDetails extends StatelessWidget {
final String symbolId;
SymbolDetails({this.symbolId});
#override
Widget build(BuildContext context) {
var _api = IOWebSocketChannel.connect('wss://api.hitbtc.com/api/2/ws');
var client = json_rpc.Client(_api.cast());
client.sendNotification(
'subscribeTicker',
{'symbol': '$symbolId'},
);
return Scaffold(
appBar: AppBar(
title: Text('$symbolId details'),
),
body: StreamBuilder(
stream: _api.stream,
builder: (BuildContext context, AsyncSnapshot snapshot) {
if (snapshot.connectionState == ConnectionState.none) {
return Center(
child: Text('Please check your internet connection'),
);
} else if (!snapshot.hasData) {
return Center(child: CircularProgressIndicator());
}
String _snapshotData = snapshot.data;
Map _response = json.decode(_snapshotData);
return ListView(
children: [
ListTile(
title: Text('Ask price:'),
trailing: Text(
'${_response['params']['ask']}',
style: TextStyle(fontWeight: FontWeight.bold),
),
),
ListTile(
title: Text('Bid price:'),
trailing: Text(
'${_response['params']['bid']}',
style: TextStyle(fontWeight: FontWeight.bold),
),
),
],
);
},
),
);
}
}
I came up with a more fleshed-out example that runs on MongoDB. It is also null-safe. Here is the API I came up with:
import 'package:shelf/shelf_io.dart' as shelf_io;
import 'package:shelf_web_socket/shelf_web_socket.dart';
import 'package:web_socket_channel/web_socket_channel.dart';
import 'package:mongo_dart/mongo_dart.dart' as mongo;
void main() async {
final handler = webSocketHandler((WebSocketChannel socket){
final server = Server(socket.cast<String>());
server.registerMethod('hello', () async{
mongo.Db db = mongo.Db('mongodb://127.0.0.1:27017/obj1');
await db.open();
var list = await db.collection('Person').find(null).toList();
// await db.close();
return list;
});
server.listen();
});
final server = await shelf_io.serve(handler, '127.0.0.1', 4042);
print('Serving at ws://${server.address.host}:${server.port}');
}
Here is the Flutter client:
import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:json_rpc_2/json_rpc_2.dart' as json_rpc;
import 'package:web_socket_channel/io.dart';
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
// This widget is the root of your application.
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
// This is the theme of your application.
//
// Try running your application with "flutter run". You'll see the
// application has a blue toolbar. Then, without quitting the app, try
// changing the primarySwatch below to Colors.green and then invoke
// "hot reload" (press "r" in the console where you ran "flutter run",
// or simply save your changes to "hot reload" in a Flutter IDE).
// Notice that the counter didn't reset back to zero; the application
// is not restarted.
primarySwatch: Colors.blue,
),
home: const MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
class MyHomePage extends StatelessWidget {
final String title;
const MyHomePage({super.key, required this.title});
#override
Widget build(BuildContext context) {
var api = IOWebSocketChannel.connect(Uri.parse('ws://127.0.0.1:4042'));
var client = json_rpc.Client(api.cast());
client.sendRequest(
'hello',
);
return Scaffold(
appBar: AppBar(
title: Text(title),
),
body: StreamBuilder(
stream: api.stream,
builder: (BuildContext context, AsyncSnapshot snapshot) {
if (snapshot.connectionState == ConnectionState.none) {
return const Center(
child: Text('Please check your internet connection'),
);
} else if (!snapshot.hasData) {
return const Center(child: CircularProgressIndicator());
}
String snapshotData = snapshot.data;
Map<String,dynamic> raw = json.decode(snapshotData);List items = raw['result'];
return ListView.builder(
itemCount: items.length,
itemBuilder: (context, index) {
return ListTile(
title: Text('${items[index]["first_name"].toString()} ${items[index]["last_name"].toString()}'),
);
},
);
},
),
);
}
}
When all goes well, the end result is a formatted list of names.
I am building a login screen that passes data to a home screen and when I click on the login button nothing happens. No error but also no sending to a new screen.
here is the button code:
Widget submitButton()
{
return Container(
margin: EdgeInsets.all(10.0),
child:RaisedButton(
child: Text('LOGIN'),
onPressed: (){
if(formKey.currentState.validate()){
formKey.currentState.save();
print('Time to save $emailAddress and $passWord to my API');
Navigator.push(
context,
new MaterialPageRoute(
builder: (BuildContext context) =>
new Home()));
}
},
)
);
here is my routes.dart file
import 'package:flutter/material.dart';
import '../screens/home.dart';
import 'package:lbconnectv3/main.dart';
final routes = {
'/home': (BuildContext context) => new Home(),
'/' : (BuildContext context) => new LBConnectApp(),
};
EDIT
FULL CODE for main.dart, it basically has a form with 2 text fields for a login. No errors in console and it enters the if statement.
import 'package:flutter/material.dart';
import 'utils/validation.dart';
import 'screens/home.dart';
import 'utils/routes.dart';
void main() => runApp(new LBConnectApp());
class LBConnectApp extends StatefulWidget {
createState()
{
return new LBConnectAppState();
}
}
class LBConnectAppState extends State<LBConnectApp> with Validation
{
final formKey = GlobalKey<FormState>();
String emailAddress = '';
String passWord = '';
Widget build(context) {
return MaterialApp(
title: "LB Connect",
home: Scaffold(
backgroundColor: const Color(0xFF0099a9),
body:
Container(
margin: EdgeInsets.all(25.0),
child: Form(
key: formKey,
child: Column(
children: [
Container(
margin: EdgeInsets.only(top: 100.0),
child:Image.asset('images/lb_connect_trans.png')
),
emailField(),
passwordField(),
submitButton(),
],
),
),
)
),
);
}
Widget emailField()
{
return TextFormField(
keyboardType: TextInputType.emailAddress,
decoration : InputDecoration(
labelText: 'Email Address',
),
validator: validateEmail,
onSaved: (String value){
emailAddress = value;
},
);
}
Widget passwordField()
{
return TextFormField(
obscureText: true,
decoration : InputDecoration(
labelText: 'Password',
),
validator: validatePassword,
onSaved: (String value){
passWord = value;
},
);
}
Widget submitButton()
{
return Container(
margin: EdgeInsets.all(10.0),
child:RaisedButton(
child: Text('LOGIN'),
onPressed: (){
if(formKey.currentState.validate()){
formKey.currentState.save();
print('Time to save $emailAddress and $passWord to my API');
Navigator.push(
context,
new MaterialPageRoute(
builder: (BuildContext context) =>
new Home()));
}
},
)
);
}
}
After messing around with my app I figured out the issue :)
I had to wrap my class with a Material App and then add my routes property to it. Here is the correct code:
void main() => runApp(MaterialApp(
routes: routes,
home: LBConnectApp()
)
);
Change this line
void main() => runApp(new LBConnectApp());
with this and it will work as per your expectation
void main() => runApp(new MyApp());
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return new MaterialApp(
title: 'Flutter Demo',
theme: new ThemeData(
primarySwatch: Colors.blue,
),
debugShowCheckedModeBanner: false,
home: new LBConnectApp(),
);
}
}
I am not sure how to generate multiple ListTiles by means of loops, such as for().
I do not know how Flutter works for rendering widgets, since in Angular 2 just insert the *ngFor directives in the layout (html).
I could not find such a subject in the Flutter documentation.
main.dart
import 'package:flutter/material.dart';
void main() {
runApp(new MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return new MaterialApp(
title: "Myapp",
home: new HomePage(),
);
}
}
class HomePage extends StatelessWidget {
#override
Widget build(BuildContext context) => new Scaffold(
appBar: new AppBar(
backgroundColor: new Color(0xFF26C6DA),
),
body: new ListView (
children: <Widget>[
new Card(
child: new Column(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
const ListTile(
leading: const Icon(Icons.album),
title: const Text('The Enchanted Nightingale'),
subtitle: const Text('Music by Julie Gable. Lyrics by Sidney Stein.'),
),
],
),
),
],
)
);
}
List.generate() is useful for making small lists. For larger or infinite lists, use a ListView.builder() instead of ListView.
import 'package:flutter/material.dart';
void main() {
runApp(new MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return new MaterialApp(
title: "Myapp",
home: new HomePage(),
);
}
}
class HomePage extends StatelessWidget {
#override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(
backgroundColor: new Color(0xFF26C6DA),
),
body: new ListView.builder(
itemBuilder: (BuildContext context, int index) {
return new Card(
child: const ListTile(
leading: const Icon(Icons.album),
title: const Text('The Enchanted Nightingale'),
subtitle: const Text(
'Music by Julie Gable. Lyrics by Sidney Stein.',
),
),
);
},
),
);
}
}
Here is the example with List.generate:-
import 'package:flutter/material.dart';
void main() {
runApp(new MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return new MaterialApp(
debugShowCheckedModeBanner: false,
title: "Myapp",
home: new HomePage(),
);
}
}
class HomePage extends StatelessWidget {
#override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(
title: Text('List.generate demo'),
),
body: new ListView(
padding: const EdgeInsets.all(8),
children: new List.generate(
10,
(index) => new ListTile(
title: Text('Item $index'),
),
),
),
);
}
}