I am really struggling to understand why my code isn't working. I'm trying to pass the text from two controllers into another widget with named parameters which writes to Firebase.
My "Test" button properly prints both _titleController.text and _descriptionController.text
TextButton(
onPressed: (){
print(_titleController.text); //works fine
print(_descriptionController.text); //works fine
},
child: Text('test')
),
However when I pass these into my next widget it's blank! If I hardcore strings into these parameters it works properly:
PushNewE3 (
changeTitle: _titleController.text, //does not work (empty)
changeDescription: _descriptionController.text, //does not work (empty)
)
Full code:
class CreateE3 extends StatefulWidget {
const CreateE3({Key? key}) : super(key: key);
#override
_CreateE3State createState() => _CreateE3State();
}
class _CreateE3State extends State<CreateE3> {
final _titleController = TextEditingController();
final _descriptionController = TextEditingController();
#override
void initState(){
super.initState();
_titleController.addListener(_printLatestValue);
}
#override
void dispose(){
_titleController.dispose();
super.dispose();
}
void _printLatestValue(){
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('So Frustrating'),
),
body: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Container(
width: 800,
child: Column(
children: [
Text('Originator: **Add Current User**') ,
TextField(
maxLength: 40,
decoration: InputDecoration(
border: OutlineInputBorder(),
labelText: 'Change Title'
),
controller: _titleController,
onEditingComplete: (){
//_title = _titleController.text;
},
),
Padding(
padding: const EdgeInsets.fromLTRB(0,10,0,0),
child: TextFormField(
maxLines: 5,
decoration: InputDecoration(
border: OutlineInputBorder(),
labelText: 'Detailed Description'
),
controller: _descriptionController,
),
),
TextButton(
onPressed: (){
print(_titleController.text); //successfully prints
print(_descriptionController.text); //successfully prints
},
child: Text('test')
),
PushNewE3 (
changeTitle: _titleController.text, //DOES NOT WORK (empty)
changeDescription: _descriptionController.text, //DOES NOT WORK (empty)
)
],
),
),
],
),
);
}
}
class PushNewE3 extends StatelessWidget {
final String changeTitle;
final String changeDescription;
PushNewE3({
required this.changeTitle,
required this.changeDescription
});
#override
Widget build(BuildContext context) {
// Create a CollectionReference called users that references the firestore collection
CollectionReference notificationsE3 = FirebaseFirestore.instance.collection('notificationsE3');
Future<void> pushNewE3() {
// Call the notifications CollectionReference to add a new E3 notification
return notificationsE3
.add({
//'originator': FirebaseAuth.instance.currentUser,
'changeTitle': changeTitle,
'changeDescription': changeDescription,
})
.then((value) => print("E3 Created"))
.catchError((error) => print("Failed to create E3: $error"));
}
return TextButton(
onPressed: (){
print('start:');
print(changeTitle);
print(changeDescription);
print('-end');
},
child: Text(
"Create E3",
),
);
}
}
EDIT:
I still don't understand why the above code doesn't work. I refactored my code into a single widget and now it's working. If anyone can explain why I would still appreciate understanding as there is clearly a gap in my knowledge.
If anyone in the future runs into the same problem here is the refactored code:
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:firebase_auth/firebase_auth.dart';
import 'package:flutter/material.dart';
import 'main.dart';
var global = 'blank';
class CreateE3 extends StatefulWidget {
const CreateE3({Key? key}) : super(key: key);
#override
_CreateE3State createState() => _CreateE3State();
}
class _CreateE3State extends State<CreateE3> {
final _titleController = TextEditingController();
final _descriptionController = TextEditingController();
#override
Widget build(BuildContext context) {
// Create a CollectionReference called users that references the firestore collection
CollectionReference notificationsE3 = FirebaseFirestore.instance.collection('notificationsE3');
Future<void> pushNewE3() {
// Call the notifications CollectionReference to add a new E3 notification
return notificationsE3
.add({
//'originator': FirebaseAuth.instance.currentUser,
'changeTitle': _titleController.text,
'changeDescription': _descriptionController.text,
})
.then((value) => print("E3 Created"))
.catchError((error) => print("Failed to create E3: $error"));
}
return Scaffold(
appBar: AppBar(
title: Text(_titleController.text),
),
body: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Container(
width: 800,
child: Column(
children: [
Text('Originator: **Add Current User**') ,
TextField(
maxLength: 40,
decoration: InputDecoration(
border: OutlineInputBorder(),
labelText: 'Change Title'
),
controller: _titleController,
onChanged: (text){
setState(() {
});
},
),
Padding(
padding: const EdgeInsets.fromLTRB(0,10,0,0),
child: TextFormField(
maxLines: 5,
decoration: InputDecoration(
border: OutlineInputBorder(),
labelText: 'Detailed Description'
),
controller: _descriptionController,
),
),
TextButton(
onPressed: (){
pushNewE3();
},
child: Text('SAVE')
),
],
),
),
],
),
);
}
}
in the onPressed To pass a value and show it, you have to use setState(() { _myState = newValue; });
Something like this
TextButton(
onPressed: (){
print(_titleController.text);
print(_descriptionController.text);
setState(() { _myNewText = _titleController.text; });
},
child: Text('test')
),
I'm not sure what are you trying to do exactly but here's what I did:
1 - add a local variable _title
2 - add this code to the onPressed function:
setState(() {
_title= _titleController.text;
});
This is the whole code :
class CreateE3 extends StatefulWidget {
const CreateE3({Key? key}) : super(key: key);
#override
_CreateE3State createState() => _CreateE3State();
}
class _CreateE3State extends State<CreateE3> {
final _titleController = TextEditingController();
final _descriptionController = TextEditingController();
String _title = 'So Frustrating';
#override
void initState(){
super.initState();
}
#override
void dispose(){
_titleController.dispose();
super.dispose();
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(_title),
),
body: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Container(
width: 400,
child: Column(
children: [
Text('Originator: **Add Current User**') ,
TextField(
maxLength: 40,
decoration: InputDecoration(
border: OutlineInputBorder(),
labelText: 'Change Title'
),
controller: _titleController,
onEditingComplete: (){
//_title = _titleController.text;
},
),
Padding(
padding: const EdgeInsets.fromLTRB(0,10,0,0),
child: TextFormField(
maxLines: 5,
decoration: InputDecoration(
border: OutlineInputBorder(),
labelText: 'Detailed Description'
),
controller: _descriptionController,
),
),
TextButton(
onPressed: (){
print(_titleController.text);
print(_descriptionController.text);
setState(() {
_title = _titleController.text;
});
},
child: Text('test')
),
],
),
),
],
),
);
}
}
.........................
so this is when you first start the app :
after changing the TextField and pressing the 'test button the title in the appbar change :
Related
I have a form builded with Bloc package.
There are two options with textfields in it.
Switching between option i've made also with bloc and Visibility widget.
When I choose an option widget rebuilds, name and price values deletes.
What is the best way to save this values between choosing options?
Here is my Bloc code
class FormBloc extends Bloc<FormEvent, MyFormState> {
FormBloc() : super(MyFormState()) {
on<RadioButtonFormEvent>(_setRadioButtonState);
}
void _setRadioButtonState(
RadioButtonFormEvent event, Emitter<MyFormState> emit) async {
emit(RadioButtonFormState(
buttonIndex: event.buttonIndex,
buttonName: event.buttonName,
));
}
}
class MyFormState {}
class RadioButtonFormState extends MyFormState {
final int buttonIndex;
final String buttonName;
RadioButtonFormState({
required this.buttonIndex,
required this.buttonName,
});
}
abstract class FormEvent extends Equatable {}
class RadioButtonFormEvent extends FormEvent {
final int buttonIndex;
final String buttonName;
RadioButtonFormEvent({
required this.buttonIndex,
required this.buttonName,
});
#override
List<Object?> get props => [buttonIndex, buttonName,];
}
Here is Form code
class FormInput extends StatelessWidget {
const FormInput({super.key});
#override
Widget build(BuildContext context) {
final formBlocWatcher = context.watch<FormBloc>().state;
final nameController = TextEditingController();
final priceController = TextEditingController();
final formOneController = TextEditingController();
final formTwoController = TextEditingController();
final formThreeController = TextEditingController();
String formOptionController = '';
bool optionOneIsActive = true;
bool optionTwoIsActive = false;
if (formBlocWatcher is RadioButtonFormState) {
switch (formBlocWatcher.buttonIndex) {
case 0:
formOptionController = formBlocWatcher.buttonName;
break;
case 1:
optionTwoIsActive = true;
optionOneIsActive = false;
formOptionController = formBlocWatcher.buttonName;
break;
}
}
return Container(
padding: EdgeInsets.only(
bottom: MediaQuery.of(context).viewInsets.bottom,
top: 15,
left: 15,
right: 15),
child: Column(
mainAxisSize: MainAxisSize.min,
children: [
TextField(
controller: nameController,
decoration: const InputDecoration(hintText: 'Name'),
),
const SizedBox(height: 10),
TextField(
controller: priceController,
keyboardType: TextInputType.number,
decoration: const InputDecoration(hintText: 'Price'),
),
const SizedBox(height: 15),
OptionsWidget(),
Visibility(
visible: optionOneIsActive,
child: TextField(
controller: formOneController,
keyboardType: TextInputType.number,
decoration: const InputDecoration(hintText: 'Form one'),
)),
Visibility(
visible: optionTwoIsActive,
child: Column(
children: [
TextField(
controller: formTwoController,
keyboardType: TextInputType.number,
decoration: const InputDecoration(hintText: 'Form two'),
),
TextField(
controller: formThreeController,
keyboardType: TextInputType.number,
decoration: const InputDecoration(hintText: 'Form three'),
),
],
)),
const SizedBox(height: 10),
ElevatedButton(
onPressed: () {
BlocProvider.of<ProductsListBloc>(context).add(
AddProductEvent(
productName: nameController.text,
productPrice: int.parse(priceController.text),
productDescOne: formOneController.text,
productDescTwo: formTwoController.text,
productDescThree: formThreeController.text,
formOption: formOptionController,
),
);
},
child: Text('Create New'),
),
],
),
);
}
}
class OptionsWidget extends StatelessWidget {
OptionsWidget({super.key});
int value = 0;
Widget CustomRadioButton(String text, int index, BuildContext context) {
final formBloc = BlocProvider.of<FormBloc>(context);
final blocWatch = context.watch<FormBloc>().state;
if (blocWatch is RadioButtonFormState) {
value = blocWatch.buttonIndex;
}
return OutlinedButton(
onPressed: () {
formBloc.add(RadioButtonFormEvent(
buttonIndex: index,
buttonName: text,
));
},
style: OutlinedButton.styleFrom(
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(10),
),
side: BorderSide(color: (value == index) ? Colors.blue : Colors.grey),
),
child: Text(
text,
style: TextStyle(
color: (value == index) ? Colors.blue : Colors.grey,
),
));
}
#override
Widget build(BuildContext context) {
return Row(
children: [
CustomRadioButton("option one", 0, context),
const SizedBox(width: 15),
CustomRadioButton("option two", 1, context),
],
);
}
}
Your FormInput class should be extends from StatefulWidget, not StatelessWidget.
After this change, you should remove all TextEditingController assignments from the build() method and move them into initState().
I am trying to send a data from ontap listview screen to form screen like image below. I have searched many references on google but I can't find any references that can help me, if you can provide solutions or references, I will greatly appreciate it.
enter image description here
This is my sample code (ListPage Screen) :
const ListPage({Key? key}) : super(key: key);
#override
State<ListPage> createState() => _ListPageState();
}
class _ListPageState extends State<ListPage> {
TextEditingController textFieldController = TextEditingController();
var _controller = TextEditingController();
late bool searching, error;
var data;
late String query;
String dataurl = "https://www.something.co.id/mobile/search_data.php";
#override
void initState() {
searching = true;
error = false;
query = "";
super.initState();
}
void getSuggestion() async {
//get suggestion function
var res = await http
.post((Uri.parse(dataurl + "?query=" + Uri.encodeComponent(query))));
//in query there might be unwant character so, we encode the query to url
if (res.statusCode == 200) {
setState(() {
data = json.decode(res.body);
//update data value and UI
});
} else {
//there is error
setState(() {
error = true;
});
}
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
toolbarHeight: AppLayout.getHeight(100),
automaticallyImplyLeading: false,
title: searchField(),
backgroundColor: Styles.background,
elevation: 0.0,
),
body: SingleChildScrollView(
child: Container(
alignment: Alignment.center,
child: data == null
? Container(
padding: EdgeInsets.all(20),
child: searching
? Text("Please wait")
: Text("Search any location")
//if is searching then show "Please wait"
//else show search peopels text
)
: Container(
child: searching
? showSearchSuggestions()
: Text("Find any location"),
)
// if data is null or not retrived then
// show message, else show suggestion
),
),
);
}
Widget showSearchSuggestions() {
List suggestionlist = List.from(data["data"].map((i) {
return SearchSuggestion.fromJSON(i);
}));
//serilizing json data inside model list.
return Column(
children: suggestionlist.map((suggestion) {
return InkResponse(
// onTap: () {
// //when tapped on suggestion
// print(suggestion.id); //pint student id
// },
child: GestureDetector(
onTap: () {
_sendDataBack(context);
},
child: SizedBox(
width: double.infinity, //make 100% width
child: Card(
child: Container(
decoration: BoxDecoration(color: Styles.background),
padding: EdgeInsets.all(15),
child: Text(
suggestion.name,
style: TextStyle(
fontSize: 20,
fontWeight: FontWeight.bold,
),
),
),
),
),
),
);
}).toList(),
);
}
// 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);
}
Widget searchField() {
//search input field
return Container(
height: 50,
child: TextField(
controller: _controller,
autofocus: true,
style: Styles.textStyle,
decoration: InputDecoration(
hintStyle: TextStyle(color: Styles.colorDeepGrey),
hintText: "Search Location...",
prefixIcon: Icon(Icons.search),
suffixIcon: _controller.text.length > 0
? IconButton(
onPressed: () {
_controller.clear();
setState(() {});
},
icon: Icon(Icons.cancel, color: Colors.grey))
: null,
enabledBorder: OutlineInputBorder(
borderSide: BorderSide(
color: Styles.colorLightBlack.withOpacity(0.20),
width: 2,
),
borderRadius: BorderRadius.circular(4),
), //under line border, set OutlineInputBorder() for all side border
focusedBorder: OutlineInputBorder(
borderSide: BorderSide(
color: Styles.primaryColor,
width: 1,
),
borderRadius: BorderRadius.circular(4),
), // focused border color
), //decoration for search input field
onChanged: (value) {
query = value; //update the value of query
getSuggestion(); //start to get suggestion
},
),
);
}
}
//serarch suggestion data model to serialize JSON data
class SearchSuggestion {
String id, name;
SearchSuggestion({required this.id, required this.name});
factory SearchSuggestion.fromJSON(Map<String, dynamic> json) {
return SearchSuggestion(
id: json["id"],
name: json["name"],
);
}
}
Sample Code NextPage Screen :
class NextPage extends StatefulWidget {
#override
_NextPageState createState() => _NextPageState();
}
class _NextPageState extends State<NextPage> {
int _currentStep = 0;
StepperType stepperType = StepperType.vertical;
String text = 'Text';
var _controller = TextEditingController();
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
automaticallyImplyLeading: false,
title: Text('Flutter Stepper Demo'),
centerTitle: true,
),
body: Container(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Expanded(
child: Stepper(
type: stepperType,
physics: ScrollPhysics(),
currentStep: _currentStep,
onStepTapped: (step) => tapped(step),
onStepContinue: continued,
onStepCancel: cancel,
steps: <Step>[
//Form Pengirim
Step(
title: new Text('Location'),
content: Column(
children: <Widget>[
SizedBox(
height: 50,
child: TextField(
onTap: () {
_awaitReturnValueFromSecondScreen(context);
},
controller: _controller,
autofocus: true,
onChanged: (text) {
setState(() {});
},
style: Styles.textStyle,
textInputAction: TextInputAction.next,
decoration: InputDecoration(
hintText: 'Location',
contentPadding:
EdgeInsets.only(left: 15, right: 15),
hintStyle: TextStyle(color: Styles.colorDeepGrey),
suffixIcon: _controller.text.length > 0
? IconButton(
onPressed: () {
_controller.clear();
setState(() {});
},
icon: Icon(Icons.cancel,
color: Colors.grey))
: null,
enabledBorder: OutlineInputBorder(
borderSide: BorderSide(
color:
Styles.colorLightBlack.withOpacity(0.20),
width: 2,
),
borderRadius: BorderRadius.circular(4),
),
focusedBorder: OutlineInputBorder(
borderSide: BorderSide(
color: Styles.primaryColor,
width: 1,
),
borderRadius: BorderRadius.circular(4),
),
),
),
),
],
),
isActive: _currentStep >= 0,
state: _currentStep >= 0
? StepState.complete
: StepState.disabled,
),
],
),
),
],
),
),
);
}
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) => DataAlamat(),
));
// after the SecondScreen result comes back update the Text widget with it
setState(() {
text = result;
});
}
tapped(int step) {
setState(() => _currentStep = step);
}
continued() {
_currentStep < 2 ? setState(() => _currentStep += 1) : null;
}
cancel() {
_currentStep > 0 ? setState(() => _currentStep -= 1) : null;
}
}
Pass the tapped item value to the next page via named parameter of other page class.
class ListPage extends StatelessWidget {
const ListPage({Key? key}) : super(key: key);
#override
Widget build(BuildContext context) {
return Scaffold(
body: ListView.builder(
itemCount: 10,
itemBuilder: (context, index) {
return ListTile(
onTap: () {
Navigator.push(context, MaterialPageRoute(
builder: (context) {
return NextPage(value: index);
},
));
},
title: Text(index.toString()),
);
},
),
);
}
}
class NextPage extends StatelessWidget {
final int value;
const NextPage({Key? key, required this.value}) : super(key: key);
#override
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: Text(value.toString()),
),
);
}
}
Example in ListView screen, you have a variable called List<String> listLocations. Your ListView widget be like:
ListView.builder(
itemCount: listLocations.length,
itemBuilder: (context, index) {
return InkWell(
onTap: () => Navigator.of(context).push(MaterialPageRoute(
builder: (context) {
return SecondScreen(listLocations[index]);
},
)),
child: ...
);
}
}
And your SecondScreen is a StatefulWidget (well it is a Form screen, so it would be Stateful, not Stateless, use TextEditingController in Form widget):
import 'package:flutter/material.dart';
class SecondScreen extends StatefulWidget {
final String location;
SecondScreen(this.location, {Key? key}) : super(key: key);
#override
State<SecondScreen> createState() => _SecondScreenState();
}
class _SecondScreenState extends State<SecondScreen> {
var _textEditingController = TextEditingController();
#override
void initState() {
_textEditingController.text = widget.location;
super.initState();
}
#override
void dispose() {
_textEditingController.dispose();
super.dispose();
}
#override
Widget build(BuildContext context) {
return Container();
}
}
You need to pass the location value in init state, and don't forget to dispose it.
im trying to put the Textvalue, i have created via Texteditingcontroller into the text on the Neuigkeiten Page via controller.value, so the texteditingvalue gets displayed on the other page, but my texteditingcontroller do not get recognised in the neugkeitenpage and i cant edit anything there at all.
class InformationContentDetails extends StatefulWidget {
const InformationContentDetails({Key key}) : super(key: key);
#override
State<InformationContentDetails> createState() => _InformationContentDetails();
}
class _InformationContentDetails extends State<InformationContentDetails> {
bool isEnable = false;
var _controller = new TextEditingController(text: 'Allgemeine Informationen');
var _controller2 = TextEditingController();
String name = "Allgemeine Informationen";
String name2 = "Herzlich Willkommen ...";
textlistener(){
print("Update: ${_controller.text}");
print("Update: ${_controller2.text}");
}
#override
void initState() {
super.initState();
// Start listening to changes
_controller.addListener(textlistener);
_controller2.addListener(textlistener);
}
#override
Widget build(BuildContext context) {
return ResponsiveBuilder(
builder: (context, sizingInformation) {
var textAlignment;
if (sizingInformation.deviceScreenType == DeviceScreenType.desktop) {
textAlignment = TextAlign.left;
} else {
textAlignment = TextAlign.center;
}
return Container(
width: 650,
child: SingleChildScrollView(
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text(
"${_controller.text}",
style: titleTextStyle(sizingInformation.deviceScreenType),
textAlign: textAlignment,
),
TextField(
enabled: true,
decoration: InputDecoration(
border: OutlineInputBorder(),
hintText: "Informationen aktualisieren",
),
controller : _controller,
),
FlatButton(
child: Text('bearbeiten'),
onPressed:(){
setState((){
name = _controller.text;
isEnable = !isEnable;
});
},
),
Text(
name2,
style: descriptionTextStyle(sizingInformation.deviceScreenType),
textAlign: textAlignment,
),
Container(
child: TextField(
decoration: InputDecoration(
border: OutlineInputBorder(),
hintText: "Informationstext aktualisieren"
),
controller : _controller2,
),
),
Container(
child: FlatButton(
child: Text('bearbeiten'),
onPressed:(){
setState((){
name2 = _controller2.text;
isEnable = !isEnable;
});
},
),
),
],
)),
);
},
);
}
#override
void dispose() {
_controller.dispose();
_controller2.dispose();
super.dispose();
}
}
class NeuigkeitenContentDetails extends StatefulWidget {
const NeuigkeitenContentDetails({Key key}) : super(key: key);
#override
State<NeuigkeitenContentDetails> createState() => _NeuigkeitenContentDetailsState();
}
class _NeuigkeitenContentDetailsState extends State<NeuigkeitenContentDetails> {
#override
Widget build(BuildContext context) {
return ResponsiveBuilder(
builder: (context, sizingInformation) {
var textAlignment;
if (sizingInformation.deviceScreenType == DeviceScreenType.desktop) {
textAlignment = TextAlign.left;
} else {
textAlignment = TextAlign.center;
}
return Container(
width: 650,
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text(
'Neuigkeiten',
style: titleTextStyle(sizingInformation.deviceScreenType),
textAlign: textAlignment,
),
SizedBox(
height: 30,
),
Text(
'Herzlich Willkommen',
style: descriptionTextStyle(sizingInformation.deviceScreenType),
textAlign: textAlignment,
)
],
),
);
},
);
}
}
It isn't clear from your code what you mean by pages.
How does InformationContentDetails relate to, or interact with, NeuigkeitenContentDetails?
If you are using e.g. named routes you may want to look at e.g. Pass arguments to a named route and or Send data to a new screen, if on the other hand you need to send information between different widgets in the widget tree you may need to look at something like Provider - allowing you to read-only or watch for change and rebuild subscribed code, or other state management solutions.
Otherwise, if they exist simultaneously in the widget tree and you don't want to use a dedicated state management solution you need to pass the necessary data up-and-down through parameters which can get messy. H.t.h.
I'm trying to create a pageview that I can load a widget into that is defined in another file. This works fine, except when I try to add a callback, I get the following error:
FlutterError (setState() or markNeedsBuild() called during build.
This error is triggered when the email entered is considered to be valid (that is, when the code in the email_entry.dart calls the callback function that was passed from the account_onboarding.dart file.) I haven't been able to determine why this is happening, and no tutorials on this subject seem to exist. I am still pretty new to Dart/Flutter, so I'm hoping someone can point out what's happening (and a fix) here.
Here is my code:
-Parent widget, account_onboarding.dart
import 'package:flutter/material.dart';
import 'package:page_view_indicators/page_view_indicators.dart';
import 'package:animated_title_screen/screens/email_entry.dart';
class AccountOnboarding extends StatefulWidget {
const AccountOnboarding({Key? key}) : super(key: key);
#override
State<AccountOnboarding> createState() => _AccountOnboardingState();
}
class _AccountOnboardingState extends State<AccountOnboarding> {
final _pController = PageController(initialPage: 0);
final _currentPageNotifier = ValueNotifier<int>(0);
final List<Widget> _pages = [];
bool validEmail = false; //Callback should set this variable
#override
void initState() {
super.initState();
_pages.add( //Add the EmailEntry widget to the list
EmailEntry(emailIsValid: (p0) {
setState(() {
validEmail = p0;
});
},),
);
_pages.add(
Container(
color: Colors.blue,
child: Text("Pg2"),
),
);
_pages.add(
Container(
color: Colors.green,
child: Text("Pg3"),
),
);
}
#override
void dispose() {
_pController.dispose();
_currentPageNotifier.dispose();
super.dispose();
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(
"Create Account",
style: Theme.of(context).textTheme.headline5,
),
centerTitle: true,
actions: [
IconButton(
icon: const Icon(Icons.close),
onPressed: () => Navigator.pop(context),
),
],
),
body: Stack(
fit: StackFit.expand,
children: [
Column(
children: [
Row(
children: [
Text(
"Step ${_currentPageNotifier.value + 1} of ${_pages.length}",
),
CirclePageIndicator(
dotColor: const Color(0xFF323232),
selectedDotColor: const Color(0xFFE4231F),
size: 10,
selectedSize: 10,
currentPageNotifier: _currentPageNotifier,
itemCount: _pages.length,
),
],
),
PageView(
controller: _pController,
onPageChanged: (index) {
setState(() {
_currentPageNotifier.value = index;
});
},
children: [
for (Widget p in _pages) p, //Display all pages in _pages[]
],
),
ElevatedButton(
child: const Text("Continue"),
onPressed: () => print("Pressed 2"),
style: ElevatedButton.styleFrom(
primary: validEmail ? const Color(0xFFE1251B) : Colors.black,
textStyle: TextStyle(
fontWeight: FontWeight.bold,
fontSize: 15,
),
),
),
],
),
],
),
);
}
}
Here is the email_entry.dart code:
import 'package:flutter/material.dart';
import 'package:google_fonts/google_fonts.dart';
class EmailEntry extends StatefulWidget {
final Function(bool) emailIsValid; //Function required in constructor
const EmailEntry({Key? key, required this.emailIsValid}) : super(key: key);
#override
State<EmailEntry> createState() => _EmailEntryState();
}
class _EmailEntryState extends State<EmailEntry> {
final _emailController = TextEditingController();
FocusNode _emailFocus = FocusNode();
#override
void initState() {
super.initState();
_emailController.addListener(() => setState(() {}));
_emailFocus.addListener(() {
print("Focus email");
});
}
#override
void dispose() {
_emailController.dispose();
super.dispose();
}
bool validateEmail(String email) {
bool valid = RegExp(
r"^[a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-]+#[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,253}[a-zA-Z0-9])?(?:\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,253}[a-zA-Z0-9])?)*$")
.hasMatch(email);
if (valid) {
widget.emailIsValid(true); //Call the callback function
}
return valid;
}
#override
Widget build(BuildContext context) {
return Scaffold(
body: Stack(
children: [
Column(
children: [
Text(
"YOUR EMAIL",
style: Theme.of(context).textTheme.headline2,
),
Text(
"Please use an email address that you would like to make your login.",
style: Theme.of(context).textTheme.bodyText2,
textAlign: TextAlign.center,
),
Container(
child: Text(
"Email Address",
),
),
TextField(
controller: _emailController,
keyboardType: TextInputType.emailAddress,
focusNode: _emailFocus,
suffixIcon: getTextFieldSuffix(emailController, _emailFocus), //OFFENDING CODE
),
],
),
],
),
);
}
//THIS FUNCTION CAUSED THE ISSUE. It is code I got from a youtube //tutorial. Probably should have guessed.
Widget getTextFieldSuffix(TextEditingController controller, FocusNode node) {
if (controller.text.isNotEmpty && node.hasFocus) {
return IconButton(
color: Colors.grey.withAlpha(150),
onPressed: () => controller.clear(),
icon: const Icon(Icons.close));
} else if (controller.text.isNotEmpty && !node.hasFocus) {
return const Icon(
Icons.check,
color: Colors.green,
);
}
return Container(
width: 0,
);
}
}
in initState,you need to call addPostFrameCallback.
like this...
#override
void initState() {
super.initState();
///Add This Line
WidgetsBinding.instance?.addPostFrameCallback((timeStamp) {
///All of your code
});
}
I found out that there is some code in my production version that calls a redraw every time the user enters a letter into the textfield for the email address. This was causing a problem because the screen was already being redrawn, and I was calling setState to redraw it again. I will edit the code shown above to include the offending code.
When I click on show/hide toggle, both password and username textfield values gets deleted. I understand that, when setState rebuilds the widget tree, it resets password/username textfield values to initial blank values. I know I can get value of textfield, However I am not able to implement logic, how can I first get current username and password value, save it somewhere and then insert it back at the time widget rebuilds alongwith setState.
import 'package:flutter/material.dart';
class LoginScreen extends StatefulWidget {
#override
_LoginScreenState createState() => _LoginScreenState();
}
class _LoginScreenState extends State<LoginScreen> {
bool _showPassword = true;
#override
Widget build(BuildContext context) {
final usernameController = TextEditingController();
final passwordController = TextEditingController();
return SafeArea(
child: Scaffold(
body: Container(
child: Column(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: [
Image(image: AssetImage('images/logo.png')),
Padding(
padding: const EdgeInsets.all(16.0),
child: Column(
children: [
TextField(
controller: usernameController,
decoration: InputDecoration(
hintText: "Enter Username",
labelText: "UserName",
),
),
SizedBox(
height: 20.0,
),
TextField(
obscureText: _showPassword,
controller: passwordController,
decoration: InputDecoration(
hintText: "Enter Password",
labelText: "Password",
suffixIcon: GestureDetector(
onTap: _togglePasswordVisibility,
child: _showPassword
? Icon(Icons.visibility)
: Icon(Icons.visibility_off),
),
),
),
SizedBox(
height: 20.0,
),
RaisedButton(
onPressed: () {
//call api here to authenticate user
},
child: Text("Login"),
),
],
),
),
Column(
children: [
Text("Don't have an account! Get it in 2 easy steps"),
RaisedButton(
onPressed: () {
//take user to registration screen
},
child: Text("Register"),
),
],
),
],
),
),
),
);
}
void _togglePasswordVisibility() {
setState(() {
_showPassword = !_showPassword;
});
}
}
When you use the setState to toggle the visibility, the build method will get called to redraw that widget. Since you are initialising your TextEditingController in the build method, it get initialised again and loose the previous value. To fix this you just remove the initialisation from build method to class level.
class _LoginScreenState extends State<LoginScreen> {
bool _showPassword = true;
final usernameController = TextEditingController();
final passwordController = TextEditingController();
#override
Widget build(BuildContext context) {
return SafeArea(
//... Your code
);
}
//... Your code
}