'Missing Focus scope.' Using input text - dart

I try build a form using Flutter, I have my own StatefulWidget that return a Form with 2 Input (I try with TextField too) and a DropdownButton.
When I executed the second Input show this error: 'Missing Focus scope.'
The code:
import 'package:flutter/material.dart';
class ContactFormView extends StatefulWidget {
#override
CreateFormViewState createState() => new CreateFormViewState();
}
class CreateFormViewState extends State<ContactFormView> {
GlobalKey<FormState> _formKey = new GlobalKey<FormState>();
#override
Widget build(BuildContext context) {
return new Scaffold(
body: new Form(
key: _formKey,
child: new Column(
children: <Widget>[
new Input(
labelText: 'First Name',
onChanged: (InputValue value) {
// Logic here
}
),
new Input(
labelText: 'Last Name',
onChanged: (InputValue value) {
// Logic here
}
),
new RaisedButton(
child: new Text('SUBMIT'),
onPressed: () {
// Logic here
},
)
]
)
)
);
}
}

Finally, the problem was fixed on next updates. Right now, you can use this widget without problems. https://docs.flutter.io/flutter/widgets/Form-class.html

Related

Make cards with texts and buttons dynamically

I'm making Notes app. I made cards with text and buttons dynamically (Create by clicking the button). But I have problem with Changing Text on CURRENT card. For example, I have 3 cards with own texts and buttons and I want to change text on 2nd card but text is changing on the 3rd card. How can I solve this problem?
3 cards with texts and buttons
Change Text Page
In the past, I've tried making list to collect texts, but i dont know how to identify current card.
full main.dart
import 'package:flutter/material.dart';
import './changeTextPage.dart';
int count = 0;
String titlecard = '';
String textcard = '';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Notes',
theme: ThemeData(
primarySwatch: Colors.deepPurple
),
home: HomePage(title: 'Notes',),
);
}
}
class HomePage extends StatefulWidget {
HomePage({Key key, this.title}) : super(key: key);
final title;
#override
HomePageState createState() => HomePageState();
}
class HomePageState extends State<HomePage> {
#override
Widget build(BuildContext context) {
List<Widget> cards = new List.generate(count, (int i) => new MyCard());
return Scaffold(
appBar: AppBar(
title: Text('Notes'),
),
body: LayoutBuilder(
builder: (context, constraint) {
return Column(
children: <Widget>[
Container(
height: 650.0,
child: new ListView(
children: cards,
scrollDirection: Axis.vertical,
),
),
],
);
}
),
floatingActionButton: FloatingActionButton(
child: Icon(Icons.add),
onPressed: () {
setState(() {
Navigator.push(context, MaterialPageRoute(
builder: (context) => changeText())
);
});
},
),
);
}
}
class MyCard extends StatefulWidget {
#override
myCard createState() => myCard();
}
class myCard extends State<MyCard> {
int myCount = count;
void click() {
setState(() {
Navigator.push(context, MaterialPageRoute(
builder: (context) => setNewText())
);
});
}
#override
Widget build(BuildContext context) {
return Center(
child: Card(
child: Column(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
ListTile(
leading: Icon(Icons.album),
title: Text(titlecard),
subtitle: Text(textcard),
),
ButtonTheme.bar( // make buttons use the appropriate styles for cards
child: ButtonBar(
children: <Widget>[
FlatButton(
child: const Text('Change Text'),
onPressed: click,
),
FlatButton(
child: const Text('LISTEN'),
onPressed: () { /* ... */ },
),
],
),
),
],
),
),
);
}
}
class setNewText extends StatefulWidget {
#override
SetNewText createState() => SetNewText();
}
class SetNewText extends State<setNewText> {
final titleController = TextEditingController();
final textController = TextEditingController();
final formkey = GlobalKey<FormState>();
void _submit() {
setState(() {
if (formkey.currentState.validate()) {
formkey.currentState.save();
Navigator.pop(context);
titlecard = titleController.text;
textcard = textController.text;
}
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Change Title'),
),
body: Column(
children: <Widget>[
Card(
child: Padding(
padding: EdgeInsets.all(2.0),
child: Form(
key: formkey,
child: Column(
children: <Widget>[
TextFormField(
controller: titleController,
decoration: InputDecoration(
labelText: 'Title'
),
validator: (value) => value.length < 1 ? 'Invalid Title' : null,
onSaved: (value) => value = titleController.text,
),
TextFormField(
controller: textController,
decoration: InputDecoration(
labelText: 'Text'
),
validator: (text) => text.length < 1 ? 'Invalid Text' : null,
onSaved: (text) => text = textController.text,
)
],
),
),
),
),
FlatButton(
textColor: Colors.deepPurple,
child: Text('SUBMIT'),
onPressed: _submit,
),
],
)
);
}
}
changeTextPage.dart
import 'package:flutter/material.dart';
import './main.dart';
class changeText extends StatefulWidget {
#override
ChangeText createState() => ChangeText();
}
class ChangeText extends State<changeText> {
myCard s = myCard();
final titleController = TextEditingController();
final textController = TextEditingController();
final formkey = GlobalKey<FormState>();
void _submit() {
setState(() {
if (formkey.currentState.validate()) {
formkey.currentState.save();
Navigator.pop(context);
count++;
titlecard = titleController.text;
textcard = textController.text;
}
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Change Title'),
),
body: Column(
children: <Widget>[
Card(
child: Padding(
padding: EdgeInsets.all(2.0),
child: Form(
key: formkey,
child: Column(
children: <Widget>[
TextFormField(
controller: titleController,
decoration: InputDecoration(
labelText: 'Title'
),
validator: (value) => value.length < 1 ? 'Invalid Title' : null,
onSaved: (value) => value = titleController.text,
),
TextFormField(
controller: textController,
decoration: InputDecoration(
labelText: 'Text'
),
validator: (text) => text.length < 1 ? 'Invalid Text' : null,
onSaved: (text) => text = textController.text,
)
],
),
),
),
),
FlatButton(
textColor: Colors.deepPurple,
child: Text('SUBMIT'),
onPressed: _submit,
),
],
)
);
}
}
Okay, so you happen to make some common mistakes, one of which is critical.
most importantly don't use global variables! As you do with count, titlecard and textcard.
there is a practice to name stateful widgets with PascalCase and corresponding states just like the widget but prefixed with an underscore (_) to make it private and suffixed by the State word.
The correct approach for this (or one of them) would be to have a widget that would be your screen with a form to edit stuff and it would pop some struct with user values on submit:
class ChangeTextScreen extends StatefulWidget {
_ChangeTextScreenState createState() => _ChangeTextScreenState();
}
class _ChangeTextScreenState extends State<ChangeTextScreen> {
void _submit() {
setState(() {
formkey.currentState.save();
Navigator.pop(ChangeTextResult(title: titleController.text, text: textController.text));
});
}
// Rest of your code...
}
class ChangeTextResult {
final String title;
final String text;
ChangeTextResult({#required this.title, #required this.text});
}
You should also have a place where you store your notes in some kind of a list. Your main screen looks like a good place for it. Once your app will be bigger, think about using scoped_model or Redux or something.
So let's add a Note class and a list with your notes to your main screen:
class Note {
String title;
String text;
Note(this.title, this.text);
}
class HomePageState extends State<HomePage> {
List<Note> _notes = [Note('Test', 'Some test note')];
#override
Widget build(BuildContext context) {
ListView cards = ListView.builder(
itemCount: _notes.length,
itemBuilder: (context, index) => MyCard(
title: _notes[index].title,
text: _notes[index].text,
onEdit: (title, text) => setState(() { // We'll get back to that later
_notes[index].title = title;
_notes[index].text = text;
})
));
// (...)
Your MyCard widget (try to use better names next time) should contain some kind of information about its content, one of the best approaches would be to pass this info to its constructor, just like that:
class MyCard extends StatefulWidget {
final String title;
final String text;
final Function onEdit;
MyCard({Key key, #required this.title, #required this.text, #required this.onEdit}) : super(key: key);
#override
_MyCardState createState() => _MyCardState();
}
Having this Key parameter is a good practice.
And use those parameters in your _MyCardState class (I renamed it from _myCard):
// (...)
children: <Widget>[
ListTile(
leading: Icon(Icons.album),
title: Text(widget.title),
subtitle: Text(widget.text),
),
// (...)
Returning to the moment where you open your ChangeTextScreen, you should assign the result of Navigation.push() to a variable. This is your result, you can deal with it (once we check it for null, the user could have returned from this screen and then the result would be null).
void click() {
setState(() {
final ChangeTextResult result = Navigator.push(context, MaterialPageRoute(
builder: (context) => ChangeTextScreen())
);
if (result != null) {
widget.onEdit(result.title, result.text);
}
});
}
Do you remember that onEdit parameter (I mentioned it in a comment in the code above)? We call that parameter here.
That's it I think. I could have mixed some concepts of your app, but I think you'll manage to get my point anyways.
I quite rewrote all of your code. I think it will be easier for you to start again from scratch and have those tips in mind. Also, try to Google some similar things (like a simple Todo application) or do Getting started from flutter.io with part two! That should give you a nice idea on how to resolve that common problem in Flutter.
And also, read about good practises in Flutter and Dart. Things like correctly formatting your code are really important.
BTW that's my longest answer on Stack Overflow so far. I hope you'll appreciate that.

Passing data between screens in Flutter

As I'm learning Flutter I've come to navigation. I want to pass data between screens similarly to passing data between Activities in Android and passing data between View Controllers in iOS. How do I do it in Flutter?
Related questions:
The best way to passing data between widgets in Flutter
Flutter pass data between widgets?
Flutter/ How to pass and get data between Statefulwidget
This answer will cover both passing data forward and passing data back. Unlike Android Activities and iOS ViewControllers, different screens in Flutter are just widgets. Navigating between them involves creating something called a route and using the Navigator to push and pop the routes on and off the stack.
Passing data forward to the next screen
To send data to the next screen you do the following things:
Make the SecondScreen constructor take a parameter for the type of data that you want to send to it. In this particular example, the data is defined to be a String value and is set here with this.text.
class SecondScreen extends StatelessWidget {
final String text;
SecondScreen({Key key, #required this.text}) : super(key: key);
...
Then use the Navigator in the FirstScreen widget to push a route to the SecondScreen widget. You put the data that you want to send as a parameter in its constructor.
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => SecondScreen(text: 'Hello',),
));
The full code for main.dart is here:
import 'package:flutter/material.dart';
void main() {
runApp(MaterialApp(
title: 'Flutter',
home: FirstScreen(),
));
}
class FirstScreen extends StatefulWidget {
#override
_FirstScreenState createState() {
return _FirstScreenState();
}
}
class _FirstScreenState extends State<FirstScreen> {
// this allows us to access the TextField text
TextEditingController textFieldController = TextEditingController();
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: Text('First screen')),
body: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Padding(
padding: const EdgeInsets.all(32.0),
child: TextField(
controller: textFieldController,
style: TextStyle(
fontSize: 24,
color: Colors.black,
),
),
),
RaisedButton(
child: Text(
'Go to second screen',
style: TextStyle(fontSize: 24),
),
onPressed: () {
_sendDataToSecondScreen(context);
},
)
],
),
);
}
// get the text in the TextField and start the Second Screen
void _sendDataToSecondScreen(BuildContext context) {
String textToSend = textFieldController.text;
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => SecondScreen(text: textToSend,),
));
}
}
class SecondScreen extends StatelessWidget {
final String text;
// receive data from the FirstScreen as a parameter
SecondScreen({Key key, #required this.text}) : super(key: key);
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: Text('Second screen')),
body: Center(
child: Text(
text,
style: TextStyle(fontSize: 24),
),
),
);
}
}
Passing data back to the previous screen
When passing data back you need to do the following things:
In the FirstScreen, use the Navigator to push (start) the SecondScreen in an async method and wait for the result that it will return when it finishes.
final result = await Navigator.push(
context,
MaterialPageRoute(
builder: (context) => SecondScreen(),
));
In the SecondScreen, include the data that you want to pass back as a parameter when you pop the Navigator.
Navigator.pop(context, 'Hello');
Then in the FirstScreen the await will finish and you can use the result.
setState(() {
text = result;
});
Here is the complete code for main.dart for your reference.
import 'package:flutter/material.dart';
void main() {
runApp(MaterialApp(
title: 'Flutter',
home: FirstScreen(),
));
}
class FirstScreen extends StatefulWidget {
#override
_FirstScreenState createState() {
return _FirstScreenState();
}
}
class _FirstScreenState extends State<FirstScreen> {
String text = 'Text';
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: Text('First screen')),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Padding(
padding: const EdgeInsets.all(32.0),
child: Text(
text,
style: TextStyle(fontSize: 24),
),
),
RaisedButton(
child: Text(
'Go to second screen',
style: TextStyle(fontSize: 24),
),
onPressed: () {
_awaitReturnValueFromSecondScreen(context);
},
)
],
),
),
);
}
void _awaitReturnValueFromSecondScreen(BuildContext context) async {
// start the SecondScreen and wait for it to finish with a result
final result = await Navigator.push(
context,
MaterialPageRoute(
builder: (context) => SecondScreen(),
));
// after the SecondScreen result comes back update the Text widget with it
setState(() {
text = result;
});
}
}
class SecondScreen extends StatefulWidget {
#override
_SecondScreenState createState() {
return _SecondScreenState();
}
}
class _SecondScreenState extends State<SecondScreen> {
// this allows us to access the TextField text
TextEditingController textFieldController = TextEditingController();
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: Text('Second screen')),
body: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Padding(
padding: const EdgeInsets.all(32.0),
child: TextField(
controller: textFieldController,
style: TextStyle(
fontSize: 24,
color: Colors.black,
),
),
),
RaisedButton(
child: Text(
'Send text back',
style: TextStyle(fontSize: 24),
),
onPressed: () {
_sendDataBack(context);
},
)
],
),
);
}
// get the text in the TextField and send it back to the FirstScreen
void _sendDataBack(BuildContext context) {
String textToSendBack = textFieldController.text;
Navigator.pop(context, textToSendBack);
}
}
This solution is very easy by passing variables in constructor:
first page:
Navigator.of(context).push(MaterialPageRoute(builder:(context)=>SecondPage('something')));
second page:
class SecondPage extends StatefulWidget {
String something;
SecondPage(this.something);
#override
State<StatefulWidget> createState() {
return SecondPageState(this.something);
}
}
class SecondPageState extends State<SecondPage> {
String something;
SecondPageState(this.something);
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
//now you have passing variable
title: Text(something),
),
...
}
Get Perfect Solution :
From 1st Screen navigate to others as:
Navigator.pushNamed(context, "second",arguments: {"name" :
"Bijendra", "rollNo": 65210});
},
On Second Screen in build method get as :
#override
Widget build(BuildContext context) {
final Map<String, Object>rcvdData = ModalRoute.of(context).settings.arguments;
print("rcvd fdata ${rcvdData['name']}");
print("rcvd fdata ${rcvdData}");
return Scaffold(appBar: AppBar(title: Text("Second")),
body: Container(child: Column(children: <Widget>[
Text("Second"),
],),),);
}
Easiest way
FirstPage.dart
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => PasswordRoute(usernameController)));
//usernameController is String value,If you want to pass multiple values add all
SecondPage.dart
class PasswordRoute extends StatefulWidget {
final String usernameController;//if you have multiple values add here
PasswordRoute(this.usernameController, {Key key}): super(key: key);//add also..example this.abc,this...
#override
State<StatefulWidget> createState() => _PasswordPageState();
}
class _PasswordPageState extends State<PasswordRoute> {
#override
Widget build(BuildContext context) {
...child: Text(widget.usernameController);
}
}
Answers above are useful for a small app, but if you want to remove the headache of continuously worrying about a widgets state, Google presented the Provider package.
https://pub.dev/packages/provider
Have a look into that one, or watch these videos from Andrea Bizzotto:
https://www.youtube.com/watch?v=MkFjtCov62g // Provider: The Essential Guide
https://www.youtube.com/watch?v=O71rYKcxUgA&t=258s // Provider: Introduction
Learn how to use the Provider package, and you are set for life :)
First Screen :
//send data to second screen
Navigator.push(context, MaterialPageRoute(builder: (context) {
return WelcomeUser(usernameController.text);
}));
Second Screen :
//fetch data from first screen
final String username;
WelcomeUser(this.username);
//use data to display
body: Container(
child: Center(
child: Text("Welcome "+widget.username,
textAlign: TextAlign.center,
),
),
),
Navigators in Flutter are similar to the Intent in Android.
There are two classes we are dealing with FirstScreen and SecondScreen.
In order to pass the data between the first screen to second do the following:
First of all add parameter in the SecondScreen class constructor
Now in the FirstScreen class provide the parameter
Navigator.push(context, MaterialPageRoute(builder: (context)=>SecondScreen(key_name:"Desired Data"));
So in the above line the "key_name" is the name of the parameter given in the SecondScreen class.
The "Desired Data" is data should be passed through the key to the SecondScreen class.
That's it you are done!!!
Passing Data to back screen flutter
Home Page
import 'package:flutter/material.dart';
import 'package:flutter/src/widgets/container.dart';
import 'package:flutter/src/widgets/framework.dart';
import 'package:sqflite_offline/View/Add_data.dart';
class HomeScreen extends StatefulWidget {
const HomeScreen({super.key});
#override
State<HomeScreen> createState() => _HomeScreenState();
}
class _HomeScreenState extends State<HomeScreen> {
List<Method> items = []; // => List of items that come form next page.
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Hello"),
),
floatingActionButton: FloatingActionButton(
onPressed: () {
Navigator.of(context)
.push<Method>(MaterialPageRoute(builder: (_) => AddData()))
// fetching data form next page.
.then((value) => setState(() {
if (value?.title_Ctr != "" && value?.desc_Ctr != "") {
items.add(Method(
title_Ctr: value!.title_Ctr,
desc_Ctr: value.desc_Ctr));
}
}));
},
child: Icon(Icons.add),
),
body: items.isNotEmpty
? Column(children: [
Expanded(
child: ListView.builder(
itemCount: items.length,
itemBuilder: ((context, index) {
return Container(
margin:
EdgeInsets.only(top: 10, left: 10, right: 10),
padding: EdgeInsets.only(left: 10, right: 10),
height: 80,
decoration: BoxDecoration(
color: Colors.pinkAccent,
borderRadius: BorderRadius.circular(10)),
child: Center(
child: ListTile(
title: Text(items[index].title_Ctr),
subtitle: Text(items[index].desc_Ctr),
leading: Icon(Icons.emoji_people),
),
),
);
})))
])
: Center(
child: Text("No Record Found"),
));
}
}
Add List Page
import 'package:flutter/material.dart';
import 'package:flutter/src/widgets/container.dart';
import 'package:flutter/src/widgets/framework.dart';
class AddData extends StatefulWidget {
const AddData({super.key});
#override
State<AddData> createState() => _AddDataState();
}
// Creating a Class and constructor.
class Method {
late String title_Ctr;
late String desc_Ctr;
Method({required this.title_Ctr, required this.desc_Ctr});
}
class _AddDataState extends State<AddData> {
// Creating a TextEditingController for two Fiends,
//one is for title TextField and second is for Description TextField.
TextEditingController titleCtr = TextEditingController();
TextEditingController descCtr = TextEditingController();
// Creating a Method for Passing a data to back page.
OnPressed(BuildContext context) {
var data = Method(title_Ctr: titleCtr.text, desc_Ctr: descCtr.text);
Navigator.pop(context, data);
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: Text("Add Data")),
body: Form(child: Builder(builder: (context) {
return Column(children: [
TextFormField(
controller: titleCtr,
decoration: InputDecoration(hintText: "title"),
validator: (value) {
var newValue = value ?? "";
if (newValue.isEmpty) {
return 'title is Required';
}
return null;
},
),
TextFormField(
controller: descCtr,
decoration: InputDecoration(hintText: "Description"),
validator: (value) {
var newValue = value ?? "";
if (newValue.isEmpty) {
return 'Discription is Required';
}
return null;
},
),
MaterialButton(
color: Colors.red,
onPressed: () {
if (Form.of(context)?.validate() ?? false) {
OnPressed(context);
}
},
child: Text("Save"),
)
]);
})));
}
}
screenshot
1) From where you want to push :
onPressed: () async {
await Navigator.pushNamed(context, '/edit',
arguments: userData);
setState(() {
userData = userData;
});}
2) From Where you want to pop :
void updateData() async{
WorldTime instance = locations;
await instance.getData();
Navigator.pop(context, userData);
}
If you use get package then try this . passing data with get package
check get package package link
Here's another approach.
Nothing wrong with the other answers. I've tried all of the methods mentioned using global wide widgets like provider, third-party solutions, Navigator arguments, etc. This approach differs by allowing one to chain calls and pass precise data of any type required to the widget using it. We can also gain access to a completion handler event and can use this technique without being constrained to Navigator objects.
Here's the tldr:
tldr; We have to turn our thinking on its head a bit. Data can be
passed to the called widget when you navigate to it by using final
arguments with default values in the destination widget. Using an
optional function you can get data back from the 'child' (destination)
widget.
The complete explanation can be found using this SO answer., (Gist)
I just want to be here to help that 1% who might go through what I did Lol
Don't forget to put an "await" infront of "Navigator.push" in the first page,
otherwise no data will be returned to the first page when you pop from the second page...
Passing Data to back screen flutter
First Screen
final result = await Navigator.of(context).push(MaterialPageRoute(builder: (context)=>const PaymentScreen()));
Second Screen
String selected = "Credit/Debit";
Navigator.pop(context,selected);

TextFormField inside ExpansionTile loses data when ExpansionTile collapses in Flutter

Here is my code, I've created an ExpansionTile and it has a child TextFormField.
import 'package:flutter/material.dart';
class OrderCreatePage extends StatefulWidget {
#override
_OrderCreatePageState createState() => _OrderCreatePageState();
}
class _OrderCreatePageState extends State<OrderCreatePage> {
String _userID;
TextEditingController _controllerl;
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: new Text("Create"),
),
body: ExpansionTile(
title: Text("Create"),
children: <Widget>[
TextFormField(
decoration: InputDecoration(
labelText: "User ID",
icon: Icon(Icons.face),
),
validator: (val) {},
controller: _controllerl,
onSaved: (val) => _userID = val,
)
],
),
);
}
}
Whenever I type something into the TextFormField and collapse the ExpansionTile, the data in the TextFormField is lost. I'm using this type of UI because I have to create a big form getting a lot of details. If there is no ExpansionTile, then the user has to scroll a long way.
As mentioned by - #pskink
In your Code Add under TextEditingController _controllerl; :
#override
void initState() {
super.initState();
_controllerl = TextEditingController();
}
So your Code will look like :
class _OrderCreatePageState extends State<OrderCreatePage> {
String _userID;
TextEditingController _controllerl;
#override
void initState() {
super.initState();
_controllerl = TextEditingController();
}
#override
Widget build(BuildContext context) {
return Scaffold(
....
......
https://api.flutter.dev/flutter/material/ExpansionTile/maintainState.html
ExpansionTile(maintainState: true, title: Text("text here"), ...
With this, the state of the children will be maintained after collapsing and opening.
I assume you use some sort of ScrollView to display the input fields.
The following is stated in the ExpansionTile reference:
This widget is typically used with ListView to create an "expand /
collapse" list entry. When used with scrolling widgets like ListView,
a unique PageStorageKey must be specified to enable the ExpansionTile
to save and restore its expanded state when it is scrolled in and out
of view.
So adding a PageStorageKey should do the trick:
ExpansionTile(
key: PageStorageKey('myInputField'),
title: Text("Create"),
children: <Widget>[
TextFormField(
decoration: InputDecoration(
labelText: "User ID",
icon: Icon(Icons.face),
),
validator: (val) {},
controller: _controllerl,
onSaved: (val) => _userID = val,
)
],
)

Show a text field dialog without being covered by keyboard?

I'm trying to create a SimpleDialog that allows the user to enter their name. But when it is displayed the dialog is half hidden by the on-screen keyboard:
How can I get the Dialog to be fully visible?
Edit: I find it strange that the homepage widget (FocusVisibilityDemo) recognises the reduced height and therefore adjusts the position of the 'Push Me' button to remain in the center. Unfortunately the dialog doesn't behave the same way.
Here is my code:
import 'package:flutter/material.dart';
class FocusVisibilityDemo extends StatefulWidget {
#override
_FocusVisibilityDemoState createState() => new _FocusVisibilityDemoState();
}
class _FocusVisibilityDemoState extends State<FocusVisibilityDemo> {
#override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(title: new Text('Text Dialog Demo')),
body: new Center(
child: new RaisedButton(
onPressed: _showDialog,
child: new Text("Push Me"),
),
),
);
}
_showDialog() async {
await showDialog<String>(
context: context,
child: new AlertDialog(
contentPadding: const EdgeInsets.all(16.0),
content: new Row(
children: <Widget>[
new Expanded(
child: new TextField(
autofocus: true,
decoration: new InputDecoration(
labelText: 'Full Name', hintText: 'eg. John Smith'),
),
)
],
),
actions: <Widget>[
new FlatButton(
child: const Text('CANCEL'),
onPressed: () {
Navigator.pop(context);
}),
new FlatButton(
child: const Text('OPEN'),
onPressed: () {
Navigator.pop(context);
})
],
),
);
}
}
void main() {
runApp(new MaterialApp(home: new FocusVisibilityDemo()));
}
If your use case is to add multiple TextFields inside your Dialog so your main Form does not get crowded, I think it is better if you build something more customizable than AlertDialog and SimpleDialog as they are used for simple activities (confirmations, radios..etc).
Otherwise, why do you want to use a Dialog for a single TextField ?
When we add multiple TextFields we should be careful about our design choices since other people will interact with this view to fill in the data, in this case I prefer to use fullscreenDialog property of PageRoute class. I am not sure if SimpleDialog can be suitable for that in Flutter.
Here is a quick example on how to use a FullScreenDialog, I hope this help and you should be able to modify it the way you want:
import 'package:flutter/material.dart';
void main() {
runApp(new MaterialApp(home: new MyApp(),));
}
class MyApp extends StatefulWidget {
#override
MyAppState createState() => new MyAppState();
}
class MyAppState extends State<MyApp> {
FullScreenDialog _myDialog = new FullScreenDialog();
#override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(
title: new Text("Fill this form"),
),
body: new Column(
children: <Widget>[
new TextField(controller: new TextEditingController(
text: "Add a single text field"),),
new Card(child: new ListTile(
title: new Text("Click to add your top 3 amazing skills"),
subtitle: new Text(
"${_myDialog._skillOne} ${_myDialog._skillTwo} ${_myDialog
._skillThree}"),
onTap: () {
Navigator.push(context, new MaterialPageRoute(
builder: (BuildContext context) => _myDialog,
fullscreenDialog: true,
));
},
),
),
],
)
);
}
}
class FullScreenDialog extends StatefulWidget {
String _skillOne = "You have";
String _skillTwo = "not Added";
String _skillThree = "any skills yet";
#override
FullScreenDialogState createState() => new FullScreenDialogState();
}
class FullScreenDialogState extends State<FullScreenDialog> {
TextEditingController _skillOneController = new TextEditingController();
TextEditingController _skillTwoController = new TextEditingController();
TextEditingController _skillThreeController = new TextEditingController();
#override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(
title: new Text("Add your top 3 skills"),
),
body: new Padding(child: new ListView(
children: <Widget>[
new TextField(controller: _skillOneController,),
new TextField(controller: _skillTwoController,),
new TextField(controller: _skillThreeController,),
new Row(
children: <Widget>[
new Expanded(child: new RaisedButton(onPressed: () {
widget._skillThree = _skillThreeController.text;
widget._skillTwo = _skillTwoController.text;
widget._skillOne = _skillOneController.text;
Navigator.pop(context);
}, child: new Text("Save"),))
],
)
],
), padding: const EdgeInsets.symmetric(horizontal: 20.0),)
);
}
}
EDIT
After doing some research, it seems that this is a bug in the current Flutter version, the temporary fix is also documented in this issue.
import 'package:flutter/material.dart';
void main() {
runApp(new MaterialApp(home: new FocusVisibilityDemo()));
}
class FocusVisibilityDemo extends StatefulWidget {
#override
_FocusVisibilityDemoState createState() => new _FocusVisibilityDemoState();
}
class _FocusVisibilityDemoState extends State<FocusVisibilityDemo> {
#override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(title: new Text('Text Dialog Demo')),
body: new Center(
child: new RaisedButton(
onPressed: _showDialog,
child: new Text("Push Me"),
),
),
);
}
_showDialog() async {
await showDialog<String>(
context: context,
child: new _SystemPadding(child: new AlertDialog(
contentPadding: const EdgeInsets.all(16.0),
content: new Row(
children: <Widget>[
new Expanded(
child: new TextField(
autofocus: true,
decoration: new InputDecoration(
labelText: 'Full Name', hintText: 'eg. John Smith'),
),
)
],
),
actions: <Widget>[
new FlatButton(
child: const Text('CANCEL'),
onPressed: () {
Navigator.pop(context);
}),
new FlatButton(
child: const Text('OPEN'),
onPressed: () {
Navigator.pop(context);
})
],
),),
);
}
}
class _SystemPadding extends StatelessWidget {
final Widget child;
_SystemPadding({Key key, this.child}) : super(key: key);
#override
Widget build(BuildContext context) {
var mediaQuery = MediaQuery.of(context);
return new AnimatedContainer(
padding: mediaQuery.viewInsets,
duration: const Duration(milliseconds: 300),
child: child);
}
}

How do I use radio buttons inside popup menus?

I'm trying to create a popup menu that contains selectable radio buttons in order to change a view type (e.g. gallery, cards, swipe, grid, list, etc.).
The issue I'm running into is that PopupMenu has its own callbacks for selecting values, and so does Radio and RadioListTile.
Ignore RadioListTile's onChanged
Here's my first attempt. This actually works, except that the buttons are perpetually grayed out. Giving the RadioListTiles a non-null noop function results in the buttons no longer grayed out (disabled), but then the popup menu no longer works.
new PopupMenuButton<String>(
...
itemBuilder: (ctx) => <PopupMenuEntry<String>>[
new PopupMenuItem(
child: new RadioListTile(
title: new Text("Cards"),
value: 'cards',
groupValue: _view,
onChanged: null),
value: 'cards'),
new PopupMenuItem(
child: new RadioListTile(
title: new Text("Swipe"),
value: 'swipe',
groupValue: _view,
onChanged: null),
value: 'swipe'),
],
onSelected: (String viewType) {
_view = viewType;
}));
Use RadioListTile, ignore PopupMenu
Second attempt is to ignore the PopupMenu entirely and just use RadioListTile onChanged. The buttons are not grayed-out/disabled, but are also not functional.
new PopupMenuButton<String>(
...
itemBuilder: (ctx) => <PopupMenuEntry<Null>>[
new PopupMenuItem(
child: new RadioListTile(
title: new Text("Cards"),
value: 'cards',
groupValue: _view,
onChanged: (v) => setState(() => _view = v)),
value: 'cards'),
new PopupMenuItem(
child: new RadioListTile(
title: new Text("Swipe"),
value: 'swipe',
groupValue: _view,
onChanged: (v) => setState(() => _view = v)),
value: 'swipe'),
],
));
What's the correct approach? PopupMenu works well with extremely simple menus, but the element selection is giving me conflicts. Is there a way to get a "dumb" popup menu that displays a column of widgets (styled like a menu) at the button?
I think the best solution for you would be to use CheckedPopupMenuItems instead of a radio list. The functionality should be exactly what you want to achieve, isn't it?
Here is a small example:
import 'package:flutter/widgets.dart';
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(),
);
}
}
class MyHomePage extends StatefulWidget {
#override
_MyHomePageState createState() => new _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
String _selectedView = 'Card';
#override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(
title: new Text('TestProject'),
actions: <Widget>[
new PopupMenuButton(
onSelected: (value) => setState(() => _selectedView = value),
itemBuilder: (_) => [
new CheckedPopupMenuItem(
checked: _selectedView == 'Card',
value: 'Card',
child: new Text('Card'),
),
new CheckedPopupMenuItem(
checked: _selectedView == 'Swipe',
value: 'Swipe',
child: new Text('Swipe'),
),
new CheckedPopupMenuItem(
checked: _selectedView == 'List',
value: 'List',
child: new Text('List'),
),
],
),
],
),
body: new Center(child: new Text(_selectedView)),
);
}
}
The problem is that the PopupMenuButton is maintaining the popup dialog as private state (it even pushes a new route onto the Navigator stack). Calling setState won't rebuild the items. You can use an AnimatedBuilder and a ValueNotifier to get around this.
Here's an example of a working radio button list inside a popup:
import 'package:flutter/foundation.dart';
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(),
);
}
}
class MyHomePage extends StatefulWidget {
State createState() => new MyHomePageState();
}
enum Fruit {
apple,
banana,
}
class MyHomePageState extends State<MyHomePage> {
ValueNotifier<Fruit> _selectedItem = new ValueNotifier<Fruit>(Fruit.apple);
#override
Widget build(BuildContext context) {
return new Scaffold(
body: new Center(
child: new PopupMenuButton<Fruit>(
itemBuilder: (BuildContext context) {
return new List<PopupMenuEntry<Fruit>>.generate(
Fruit.values.length,
(int index) {
return new PopupMenuItem(
value: Fruit.values[index],
child: new AnimatedBuilder(
child: new Text(Fruit.values[index].toString()),
animation: _selectedItem,
builder: (BuildContext context, Widget child) {
return new RadioListTile<Fruit>(
value: Fruit.values[index],
groupValue: _selectedItem.value,
title: child,
onChanged: (Fruit value) {
_selectedItem.value = value;
},
);
},
),
);
},
);
},
),
),
);
}
}

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