Showing selected image in alert dialog in flutter - flutter

How can i show the selected image in my alert dialog ?
In my app, i added an alert dialog which has the camera button. When user clicks the camera button, another alert dialog asks to select file from gallery. After the user selects image file from gallery, i want to show the image in the alert dialog with the camera button, but the image shows only after reopening the alert dialog.
I have posted my code below. I am new to flutter. Please can someone help me? Thanks in advance.
class Test extends StatefulWidget {
#override
_State createState() => new _State();
}
Future<File> imageFile;
class _State extends State<Test> {
Future<void> _openDailog() async {
return showDialog<void>(
context: context,
barrierDismissible: true,
builder: (BuildContext context) {
return AlertDialog(
shape:
RoundedRectangleBorder(borderRadius: BorderRadius.circular(8.0)),
title: Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
Text('Click Photo'),
Ink(
decoration: BoxDecoration(
borderRadius: BorderRadius.circular(24.0),
color: Colors.blue),
child: IconButton(
color: Colors.white,
icon: Icon(Icons.camera_alt),
onPressed: () {
_cameraOptions();
print("test");
},
),
)
],
),
content: SingleChildScrollView(
child: Container(
width: 300.0,
child: Column(
mainAxisAlignment: MainAxisAlignment.start,
crossAxisAlignment: CrossAxisAlignment.stretch,
mainAxisSize: MainAxisSize.min,
children: <Widget>[
showImage(),
InkWell(
child: Container(
margin: EdgeInsets.only(top: 8.0),
child: RaisedButton(
color: Colors.blue,
child: new Text(
"Send",
style: TextStyle(color: Colors.white),
),
onPressed: () {
Navigator.of(context).pop();
print("test");
},
),
)),
],
),
),
),
);
},
);
}
#override
Widget build(BuildContext context) {
// TODO: implement build
return Row(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
FloatingActionButton(
heroTag: null,
child: Icon(Icons.insert_drive_file),
onPressed: () {
_openDailog();
},
)
],
);
}
Future<void> _cameraOptions() {
return showDialog(
context: context,
builder: (BuildContext context) {
return AlertDialog(
content: new SingleChildScrollView(
child: new ListBody(
children: <Widget>[
FlatButton(
onPressed: () {
pickImageFromGallery(ImageSource.gallery);
Navigator.of(context).pop();
},
color: Colors.transparent,
child: new Text(
'Select From Gallery',
textAlign: TextAlign.start,
style: new TextStyle(
decoration: TextDecoration.underline,
),
),
),
],
),
),
);
});
}
pickImageFromGallery(ImageSource source) {
setState(() {
imageFile = ImagePicker.pickImage(source: source);
});
}
Widget showImage() {
return FutureBuilder<File>(
future: imageFile,
builder: (BuildContext context, AsyncSnapshot<File> snapshot) {
if (snapshot.connectionState == ConnectionState.done &&
snapshot.data != null) {
return Image.file(
snapshot.data,
width: MediaQuery.of(context).size.width,
height: 100,
);
} else if (snapshot.error != null) {
return const Text(
'Error Picking Image',
textAlign: TextAlign.center,
);
} else {
return const Text(
'No Image Selected',
textAlign: TextAlign.center,
);
}
},
);
}
}

That is because you would need to setState() however you can't do that in an alert dialogue as it doesn't have its own state, the workaround for that would be to have the dialogue be its own stateful widget. Please check out this article as it shows how to do that. If you faced problems let me know!
import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';
import 'package:path_provider/path_provider.dart';
void main() {
runApp(new MaterialApp(
home: new MyHomePage(),
));
}
class MyHomePage extends StatefulWidget {
#override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
int _selectedIndex = 0;
Widget build(BuildContext context) {
return new Scaffold(
appBar: AppBar(
title: Text("StackoverFlow"),
),
body: Container(),
floatingActionButton: FloatingActionButton(
onPressed: () async {
await _dialogCall(context);
},
),
);
}
Future<void> _dialogCall(BuildContext context) {
return showDialog(
context: context,
builder: (BuildContext context) {
return MyDialog();
});
}
}
class MyDialog extends StatefulWidget {
#override
_MyDialogState createState() => new _MyDialogState();
}
class _MyDialogState extends State<MyDialog> {
String imagePath;
Image image;
#override
Widget build(BuildContext context) {
return AlertDialog(
content: new SingleChildScrollView(
child: new ListBody(
children: <Widget>[
Container(child: image!= null? image:null),
GestureDetector(
child: Row(
children: <Widget>[
Icon(Icons.camera),
SizedBox(width: 5),
Text('Take a picture '),
],
),
onTap: () async {
await getImageFromCamera();
setState(() {
});
}),
Padding(
padding: EdgeInsets.all(8.0),
),
],
),
),
);
}
Future getImageFromCamera() async {
var x = await ImagePicker.pickImage(source: ImageSource.camera);
imagePath = x.path;
image = Image(image: FileImage(x));
}
}

Try this solution with GestureDetector() .it works
onTap:()async{
var image = await ImagePicker.pickImage(
source: ImageSource.gallery).whenComplete((){
setState(() {
});
}
);
setState(() {
_image = image;
});
},

Related

Flutter Sqflite Toggling between Screens based on Login Status creates null operator used on null value error

I am trying to toggle between Login Screen and HomeScreen based on the user status. The logic seems to be working as long as I don't put HomeScreen.
I replaced HomeScreen with a different screen to check and the app works as it should. It displays different screens on hot restart based on the user's login status. But as soon as I try to put HomeScreen I get null operator used on null value error.
Here is the toggle logic.
class Testing extends StatefulWidget {
const Testing({super.key});
#override
State<Testing> createState() => _TestingState();
}
class _TestingState extends State<Testing> {
#override
Widget build(BuildContext context) {
return FutureBuilder(
future: TodoServiceHelper().checkifLoggedIn(),
builder: ((context, snapshot) {
if (!snapshot.hasData) {
return Container(
child: Center(
child: CircularProgressIndicator(),
),
);
}
if (snapshot.hasError) {
print(snapshot.hasError);
return Container(
child: Center(
child: CircularProgressIndicator(),
),
);
}
if (snapshot.data!.isNotEmpty) {
print(snapshot.data);
return RegisterPage();
// returning HomePage gives null check operator used on null value error
} else
return Login();
}),
);
}
}
Here is the HomeScreen
class HomePage extends StatefulWidget {
String? username;
HomePage({this.username});
#override
State<HomePage> createState() => _HomePageState();
}
class _HomePageState extends State<HomePage> {
final GlobalKey<FormState> formKey = GlobalKey();
TextEditingController termController = TextEditingController();
void clearText() {
termController.clear();
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
actions: <Widget>[
IconButton(
onPressed: () {
User loginUser =
User(username: widget.username.toString(), isLoggedIn: false);
TodoServiceHelper().updateUserName(loginUser);
Navigator.pushReplacement(
context,
MaterialPageRoute(
builder: (BuildContext context) => Login()));
},
icon: Icon(Icons.logout),
color: Colors.white,
)
],
title: FutureBuilder(
future: TodoServiceHelper().getTheUser(widget.username!),
builder: (context, snapshot) {
if (!snapshot.hasData) {
return Container(
child: Center(
child: CircularProgressIndicator(),
),
);
}
return Text(
'Welcome ${snapshot.data!.username}',
style: TextStyle(color: Colors.white),
);
}),
),
body: SingleChildScrollView(
child: Column(children: [
Column(
children: [
Padding(
padding: const EdgeInsets.all(12.0),
child: Form(
key: formKey,
child: Column(
children: <Widget>[
TextFormField(
controller: termController,
decoration: InputDecoration(
filled: true,
fillColor: Colors.white,
enabledBorder: OutlineInputBorder(),
labelText: 'search todos',
),
),
TextButton(
onPressed: () async {
await Navigator.push(
context,
MaterialPageRoute(
builder: (context) => ShowingSerachedTitle(
userNamee: widget.username!,
searchTerm: termController.text,
)),
);
print(termController.text);
clearText();
setState(() {});
},
child: Text(
'Search',
)),
Divider(
thickness: 3,
),
],
),
),
),
],
),
Container(
child: Stack(children: [
Positioned(
bottom: 0,
child: Text(
' done Todos',
style: TextStyle(fontSize: 12),
),
),
IconButton(
onPressed: () async {
await Navigator.push(
context,
MaterialPageRoute(
builder: (context) =>
CheckingStuff(userNamee: widget.username!)),
);
setState(() {});
},
icon: Icon(Icons.filter),
),
]),
),
Divider(
thickness: 3,
),
Container(
child: TodoListWidget(name: widget.username!),
height: 1000,
width: 380,
)
]),
),
floatingActionButton: FloatingActionButton(
backgroundColor: Color.fromARGB(255, 255, 132, 0),
onPressed: () async {
await showDialog(
barrierDismissible: false,
context: context,
builder: ((context) {
return AddNewTodoDialogue(name: widget.username!);
}),
);
setState(() {});
},
child: Icon(Icons.add),
),
);
}
}
The function used to return user with loginStatus true
Future<List<User>> checkifLoggedIn() async {
final Database db = await initializeDB();
final List<Map<String, Object?>> result = await db.query(
'users',
where: 'isLoggedIn = ?',
whereArgs: ['1'],
);
List<User> filtered = [];
for (var item in result) {
filtered.add(User.fromMap(item));
}
return filtered;
}
the problem is here
you used ! sign on a nullable String , and this string is nullable,
try to use this operation (??) so make it
widget.username??"" by this line you will check if the user name is null it will be replaced by an empty string.

How to automatically close a dialog box without clicking in flutter?

I have a dialog box, when I click on the Send Again button, I make a request to the server and, if successful, another _emailSentDialog dialog box opens from above. How can I make the first EmailVerifyDialog automatically close when the second _emailSentDialog is opened?
class EmailVerifyDialog extends StatelessWidget {
final CurrentEmailCubit cubit;
const EmailVerifyDialog({Key? key, required this.cubit}) : super(key: key);
#override
Widget build(BuildContext context) {
final size = MediaQuery.of(context).size;
return AlertDialogGradientBorder(
height: size.height * .5,
child: SizedBox(
width: size.width,
child: Padding(
padding: const EdgeInsets.only(bottom: 35),
child: Column(
children: [
Padding(
padding: const EdgeInsets.symmetric(horizontal: 45),
child: RichText(
textAlign: TextAlign.center,
text: TextSpan(
children: [
WidgetSpan(
child: FittedBox(
child: Row(
children: [
const Text(
'Didn’t recieve a link? ',
style: constants.Styles.smallBookTextStyleWhite,
),
TextButton(
style: TextButton.styleFrom(
padding: EdgeInsets.zero),
onPressed: () async {
await cubit
.sendConfirmationCode(
email: cubit.currentEmail)
.then((value) => {
if (value)
{
_emailSentDialog(context),
}
else
{
_errorNotification(context),
}
});
log(cubit.currentEmail);
},
child: const Text(
'Send Again',
style: constants
.Styles.smallBookUnderlineTextStyleWhite,
),
),
],
),
),
),
],
),
),
),
],
),
),
),
);
}
void _closeDialog(BuildContext context) {
Navigator.pop(context);
}
void _emailSentDialog(context) async {
showDialog(
context: context,
builder: (BuildContext context) => const EmailSentDialog(),
);
}
I was referring this way
onPressed: () async {
setState(() {
text = "checking on Server";
});
final showSecondDialog = await serverResult();
if (showSecondDialog) {
if (!mounted) return;
Navigator.of(context).pop();
showDialog2(context);
}
},
class TestDialogActivity extends StatefulWidget {
const TestDialogActivity({Key? key}) : super(key: key);
#override
State<TestDialogActivity> createState() => _TestDialogActivityState();
}
class _TestDialogActivityState extends State<TestDialogActivity> {
showDialog2(context) async {
showDialog(
context: context,
builder: (context) => AlertDialog(
content: Column(
mainAxisSize: MainAxisSize.min,
children: [
TextButton(
onPressed: () async {
Navigator.of(context).pop();
},
child: Text(" close Second dialog "))
],
),
),
);
}
Future<bool> serverResult() async {
await Future.delayed(Duration(seconds: 1));
return true;
}
showDialog1(context) async {
String text = "sendAgain";
showDialog(
context: context,
builder: (context) => StatefulBuilder(
builder: (context, setState) => AlertDialog(
content: Column(
mainAxisSize: MainAxisSize.min,
children: [
TextButton(
onPressed: () async {
setState(() {
text = "checking on Server";
});
final showSecondDialog = await serverResult();
if (showSecondDialog) {
if (!mounted) return;
Navigator.of(context).pop();
showDialog2(context);
}
},
child: Text("$text"))
],
),
),
),
);
}
#override
Widget build(BuildContext context) {
return Scaffold(
floatingActionButton: FloatingActionButton(
onPressed: () => showDialog1(context),
),
);
}
}

Flutter Speech to text navigate next Sacreen after finishing up the speech

Hello friends my problem is that I want perform task there small icon on menu bar mic icon when user click on Mic it show dialog box and when they speak text word appear on dialog box when user finished up there speech it's goes to next screen I have done all thing but problem is that when user finishing there speech i unable to go on next sacreen this only issue any expert can help here is picture below what i actually i want
Here is when user speech
When they complete their speech go next sacreen
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:speech_to_text/speech_recognition_result.dart';
import 'package:speech_to_text/speech_to_text.dart' as stt;
import 'package:speech_to_text/speech_to_text.dart';
import 'package:avatar_glow/avatar_glow.dart';
class Booknames extends StatefulWidget {
const Booknames({Key? key}) : super(key: key);
#override
_BooknamesState createState() => _BooknamesState();
}
class _BooknamesState extends State<Booknames> {
stt.SpeechToText speechToText = stt.SpeechToText();
bool islistening = false;
late String text = 'Example:Gensis chapter verse 5';
bool complete=false;
#override
void initState() {
// TODO: implement initState
super.initState();
_initSpeech();
}
/// This has to happen only once per app
void _initSpeech() async {
speechToText.initialize();
}
final GlobalKey _dialogKey = GlobalKey();
_showDialog() async {
showDialog(
context: context,
barrierDismissible: true,
builder: (BuildContext context) {
return StatefulBuilder(
key: _dialogKey,
builder: (context, setState) {
return Container(
child: Dialog(
child: Padding(
padding: EdgeInsets.all(8),
child: Column(
mainAxisSize: MainAxisSize.min,
children: [
AvatarGlow(
glowColor: Colors.blue,
endRadius: 80,
duration: Duration( milliseconds: 2500),
repeat: true,
showTwoGlows: true,
repeatPauseDuration: Duration( milliseconds: 150),
child: Material(
elevation: 5,
shape: CircleBorder(),
child: CircleAvatar(
backgroundColor: Colors.white,
child: Icon(Icons.mic, color: Colors.blue, size: 40,),
radius: 40,
),
),
),
Text(text),
SizedBox(height: 10),
TextButton(
onPressed: () => Navigator.pop(context, false), // passing false
child: Text('Cancel Voice'),
),
],
),
),
),
);
},
);
},
);
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
actions: <Widget>[
new IconButton(
icon: new Icon(islistening ? Icons.mic : Icons.mic_none),
highlightColor: Colors.pink,
onPressed: () {
setState(() {
_listen();
_showDialog();
});
},
),
],
elevation: 0,
title: Text('The Bible Multiversion', style: TextStyle(
fontSize: 20
),),
centerTitle: true,
),
body: Column(
mainAxisAlignment: MainAxisAlignment.start,
crossAxisAlignment: CrossAxisAlignment.start,
children: [
Expanded(
child: ListView.separated(
shrinkWrap: true,
itemCount: 1,
separatorBuilder: (BuildContext context, int index) =>
Divider(height: 1),
itemBuilder: (context, index) {
return Column(
children: [
],
);
},
),
),
],
),
);
}
void _listen() async {
if (!islistening) {
bool available = await speechToText.initialize(
onStatus: (val) => print('onStatus: $val'),
onError: (val) => print('onError: $val'),
);
if (available) {
setState(() {
islistening = true;
});
speechToText.listen(
onResult: (result) =>
setState(() {
text = result.recognizedWords;
if (_dialogKey.currentState != null && _dialogKey.currentState!.mounted) {
_dialogKey.currentState!.setState(() {
text =result.recognizedWords;
});
}
})
);
}
} else {
setState(() => islistening = false
);
speechToText.stop();
}
}
}

How to display taken photo correctly?

I have custom app where I use dialogs to quiz with users to save places. When I take photo file is saved to device but not displayed. Where I have an error in my code where I tried display image?
Code:
import 'dart:io';
import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';
import 'package:path/path.dart' as path;
import 'package:path_provider/path_provider.dart' as syspaths;
class PlacesListScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
return _Map();
}
}
class _Map extends StatefulWidget {
#override
_MapState createState() => _MapState();
}
class _MapState extends State<_Map> {
File _storedImage;
final picker = ImagePicker();
final _titleController = TextEditingController();
Future _takeImage() async {
final pickedFile = await picker.getImage(
source: ImageSource.camera,
maxWidth: 600,
);
if (pickedFile == null) {
return;
}
_storedImage = File(pickedFile.path);
final appDir = await syspaths.getApplicationDocumentsDirectory();
final fileName = path.basename(_storedImage.path);
await _storedImage.copy('${appDir.path}/$fileName');
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Locations'),
actions: <Widget>[
IconButton(
icon: Icon(Icons.add),
onPressed: () {
return showDialog(
context: context,
builder: (ctx) => AlertDialog(
title: Text(
"Do you want add current place to the map?",
textAlign: TextAlign.center,
),
content: TextField(
decoration: InputDecoration(labelText: 'Place title'),
controller: _titleController,
),
actions: <Widget>[
FlatButton(
onPressed: () {
Navigator.of(ctx).pop();
},
child: Text("No"),
),
FlatButton(
onPressed: () {
return showDialog(
context: context,
builder: (ctx) => AlertDialog(
title: Text(
"Do you want take photo of current place?",
textAlign: TextAlign.center,
),
content: Container(
width: 150,
height: 100,
decoration: BoxDecoration(
border:
Border.all(width: 1, color: Colors.grey),
),
child: _storedImage != null
? Image.file(
_storedImage,
fit: BoxFit.cover,
width: double.infinity,
)
: Text('No photo taken yet',
textAlign: TextAlign.center),
alignment: Alignment.center,
),
actions: <Widget>[
FlatButton(
onPressed: () {
Navigator.of(ctx).pop();
},
child: Text("No"),
),
FlatButton(
onPressed: _takeImage,
child: Text("Yes"),
),
],
),
);
},
child: Text("Yes"),
),
],
),
);
// Navigator.of(context).pushNamed(AddPlaceScreen.routeName);
},
),
],
),
body: Text("Application Content")
);
}
}
Here is photo not displayed:
Image.file(
_storedImage,
fit: BoxFit.cover,
width: double.infinity,
)
Maybe I have an error on states or on another part of my code?
You can copy paste run full code below
You can use StatefulBuilder and pass StateSetter to _takeImage and call setState
code snippet
Future _takeImage(StateSetter setState) async {
...
setState(() {
_storedImage = File(pickedFile.path);
});
...
return showDialog(
context: context,
builder: (ctx) => StatefulBuilder(builder:
(BuildContext context,
StateSetter setState) {
...
FlatButton(
onPressed: () =>
_takeImage(setState),
child: Text("Yes"),
),
working demo
full code
import 'package:flutter/material.dart';
import 'dart:io';
import 'package:image_picker/image_picker.dart';
import 'package:path/path.dart' as path;
import 'package:path_provider/path_provider.dart' as syspaths;
class PlacesListScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
return _Map();
}
}
class _Map extends StatefulWidget {
#override
_MapState createState() => _MapState();
}
class _MapState extends State<_Map> {
File _storedImage;
final picker = ImagePicker();
final _titleController = TextEditingController();
Future _takeImage(StateSetter setState) async {
final pickedFile = await picker.getImage(
source: ImageSource.camera,
maxWidth: 600,
);
if (pickedFile == null) {
return;
}
setState(() {
_storedImage = File(pickedFile.path);
});
final appDir = await syspaths.getApplicationDocumentsDirectory();
final fileName = path.basename(_storedImage.path);
await _storedImage.copy('${appDir.path}/$fileName');
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Locations'),
actions: <Widget>[
IconButton(
icon: Icon(Icons.add),
onPressed: () {
return showDialog(
context: context,
builder: (ctx) => AlertDialog(
title: Text(
"Do you want add current place to the map?",
textAlign: TextAlign.center,
),
content: TextField(
decoration:
InputDecoration(labelText: 'Place title'),
controller: _titleController,
),
actions: <Widget>[
FlatButton(
onPressed: () {
Navigator.of(ctx).pop();
},
child: Text("No"),
),
FlatButton(
onPressed: () {
return showDialog(
context: context,
builder: (ctx) => StatefulBuilder(builder:
(BuildContext context,
StateSetter setState) {
return AlertDialog(
title: Text(
"Do you want take photo of current place?",
textAlign: TextAlign.center,
),
content: Container(
width: 150,
height: 100,
decoration: BoxDecoration(
border: Border.all(
width: 1,
color: Colors.grey),
),
child: _storedImage != null
? Image.file(
_storedImage,
fit: BoxFit.cover,
width: double.infinity,
)
: Text('No photo taken yet',
textAlign:
TextAlign.center),
alignment: Alignment.center,
),
actions: <Widget>[
FlatButton(
onPressed: () {
Navigator.of(ctx).pop();
},
child: Text("No"),
),
FlatButton(
onPressed: () =>
_takeImage(setState),
child: Text("Yes"),
),
],
);
}));
},
child: Text("Yes"),
),
],
));
// Navigator.of(context).pushNamed(AddPlaceScreen.routeName);
},
),
],
),
body: Text("Application Content"));
}
}
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
visualDensity: VisualDensity.adaptivePlatformDensity,
),
home: PlacesListScreen(),
);
}
}

How to work with progress indicator in flutter?

I'm newbie in flutter and wanted to know what is better way to add CircularProgressIndicator in my layout. For example, my login view. This view have username, password and login Button. I did want create a overlay layout (with Opacity) that, when loading, show progress indicator like I use in NativeScript, but I'm little confused with how to do and too if it is the better way. On NativeScript, for example, I add IndicatorActivity in main layout and set busy to true or false, so it overlay all view components when is loading.
Edit:
I was able to reach this result:
void main() {
runApp(new MyApp());
}
class MyApp extends StatelessWidget {
// This widget is the root of your application.
#override
Widget build(BuildContext context) {
return new MaterialApp(
title: 'Flutter Demo',
theme: new ThemeData(
primarySwatch: Colors.blue,
),
home: new MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
#override
_MyHomePageState createState() => new _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
bool _loading = false;
void _onLoading() {
setState(() {
_loading = true;
new Future.delayed(new Duration(seconds: 3), _login);
});
}
Future _login() async{
setState((){
_loading = false;
});
}
#override
Widget build(BuildContext context) {
var body = new Column(
children: <Widget>[
new Container(
height: 40.0,
padding: const EdgeInsets.all(10.0),
margin: const EdgeInsets.fromLTRB(15.0, 150.0, 15.0, 0.0),
decoration: new BoxDecoration(
color: Colors.white,
),
child: new TextField(
decoration: new InputDecoration.collapsed(hintText: "username"),
),
),
new Container(
height: 40.0,
padding: const EdgeInsets.all(10.0),
margin: const EdgeInsets.all(15.0),
decoration: new BoxDecoration(
color: Colors.white,
),
child: new TextField(
decoration: new InputDecoration.collapsed(hintText: "password"),
),
),
],
);
var bodyProgress = new Container(
child: new Stack(
children: <Widget>[
body,
new Container(
alignment: AlignmentDirectional.center,
decoration: new BoxDecoration(
color: Colors.white70,
),
child: new Container(
decoration: new BoxDecoration(
color: Colors.blue[200],
borderRadius: new BorderRadius.circular(10.0)
),
width: 300.0,
height: 200.0,
alignment: AlignmentDirectional.center,
child: new Column(
crossAxisAlignment: CrossAxisAlignment.center,
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
new Center(
child: new SizedBox(
height: 50.0,
width: 50.0,
child: new CircularProgressIndicator(
value: null,
strokeWidth: 7.0,
),
),
),
new Container(
margin: const EdgeInsets.only(top: 25.0),
child: new Center(
child: new Text(
"loading.. wait...",
style: new TextStyle(
color: Colors.white
),
),
),
),
],
),
),
),
],
),
);
return new Scaffold(
appBar: new AppBar(
title: new Text(widget.title),
),
body: new Container(
decoration: new BoxDecoration(
color: Colors.blue[200]
),
child: _loading ? bodyProgress : body
),
floatingActionButton: new FloatingActionButton(
onPressed: _onLoading,
tooltip: 'Loading',
child: new Icon(Icons.check),
),
);
}
}
I'm still adapting to the idea of ​​states. This code is within the expected when working with flutter?
In flutter, there are a few ways to deal with Asynchronous actions.
A lazy way to do it can be using a modal. Which will block the user input, thus preventing any unwanted actions.
This would require very little change to your code. Just modifying your _onLoading to something like this :
void _onLoading() {
showDialog(
context: context,
barrierDismissible: false,
builder: (BuildContext context) {
return Dialog(
child: new Row(
mainAxisSize: MainAxisSize.min,
children: [
new CircularProgressIndicator(),
new Text("Loading"),
],
),
);
},
);
new Future.delayed(new Duration(seconds: 3), () {
Navigator.pop(context); //pop dialog
_login();
});
}
The most ideal way to do it is using FutureBuilder and a stateful widget. Which is what you started.
The trick is that, instead of having a boolean loading = false in your state, you can directly use a Future<MyUser> user
And then pass it as argument to FutureBuilder, which will give you some info such as "hasData" or the instance of MyUser when completed.
This would lead to something like this :
#immutable
class MyUser {
final String name;
MyUser(this.name);
}
class MyApp extends StatelessWidget {
// This widget is the root of your application.
#override
Widget build(BuildContext context) {
return new MaterialApp(
title: 'Flutter Demo',
home: new MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
#override
_MyHomePageState createState() => new _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
Future<MyUser> user;
void _logIn() {
setState(() {
user = new Future.delayed(const Duration(seconds: 3), () {
return new MyUser("Toto");
});
});
}
Widget _buildForm(AsyncSnapshot<MyUser> snapshot) {
var floatBtn = new RaisedButton(
onPressed:
snapshot.connectionState == ConnectionState.none ? _logIn : null,
child: new Icon(Icons.save),
);
var action =
snapshot.connectionState != ConnectionState.none && !snapshot.hasData
? new Stack(
alignment: FractionalOffset.center,
children: <Widget>[
floatBtn,
new CircularProgressIndicator(
backgroundColor: Colors.red,
),
],
)
: floatBtn;
return new ListView(
padding: const EdgeInsets.all(15.0),
children: <Widget>[
new ListTile(
title: new TextField(),
),
new ListTile(
title: new TextField(obscureText: true),
),
new Center(child: action)
],
);
}
#override
Widget build(BuildContext context) {
return new FutureBuilder(
future: user,
builder: (context, AsyncSnapshot<MyUser> snapshot) {
if (snapshot.hasData) {
return new Scaffold(
appBar: new AppBar(
title: new Text("Hello ${snapshot.data.name}"),
),
);
} else {
return new Scaffold(
appBar: new AppBar(
title: new Text("Connection"),
),
body: _buildForm(snapshot),
);
}
},
);
}
}
For me, one neat way to do this is to show a SnackBar at the bottom while the Signing-In process is taken place, this is a an example of what I mean:
Here is how to setup the SnackBar.
Define a global key for your Scaffold
final GlobalKey<ScaffoldState> _scaffoldKey = new GlobalKey<ScaffoldState>();
Add it to your Scaffold key attribute
return new Scaffold(
key: _scaffoldKey,
.......
My SignIn button onPressed callback:
onPressed: () {
_scaffoldKey.currentState.showSnackBar(
new SnackBar(duration: new Duration(seconds: 4), content:
new Row(
children: <Widget>[
new CircularProgressIndicator(),
new Text(" Signing-In...")
],
),
));
_handleSignIn()
.whenComplete(() =>
Navigator.of(context).pushNamed("/Home")
);
}
It really depends on how you want to build your layout, and I am not sure what you have in mind.
Edit
You probably want it this way, I have used a Stack to achieve this result and just show or hide my indicator based on onPressed
class TestSignInView extends StatefulWidget {
#override
_TestSignInViewState createState() => new _TestSignInViewState();
}
class _TestSignInViewState extends State<TestSignInView> {
bool _load = false;
#override
Widget build(BuildContext context) {
Widget loadingIndicator =_load? new Container(
color: Colors.grey[300],
width: 70.0,
height: 70.0,
child: new Padding(padding: const EdgeInsets.all(5.0),child: new Center(child: new CircularProgressIndicator())),
):new Container();
return new Scaffold(
backgroundColor: Colors.white,
body: new Stack(children: <Widget>[new Padding(
padding: const EdgeInsets.symmetric(vertical: 50.0, horizontal: 20.0),
child: new ListView(
children: <Widget>[
new Column(
mainAxisAlignment: MainAxisAlignment.center,
crossAxisAlignment: CrossAxisAlignment.center
,children: <Widget>[
new TextField(),
new TextField(),
new FlatButton(color:Colors.blue,child: new Text('Sign In'),
onPressed: () {
setState((){
_load=true;
});
//Navigator.of(context).push(new MaterialPageRoute(builder: (_)=>new HomeTest()));
}
),
],),],
),),
new Align(child: loadingIndicator,alignment: FractionalOffset.center,),
],));
}
}
Create a bool isLoading and set it to false. With the help of ternary operator, When user clicks on login button set state of isLoading to true. You will get circular loading indicator in place of login button
isLoading ? new PrimaryButton(
key: new Key('login'),
text: 'Login',
height: 44.0,
onPressed: setState((){isLoading = true;}))
: Center(
child: CircularProgressIndicator(),
),
You can see Screenshots how it looks while before login is clicked
After login is clicked
In mean time you can run login process and login user. If user credentials are wrong then again you will setState of isLoading to false, such that loading indicator will become invisible and login button visible to user.
By the way, primaryButton used in code is my custom button. You can do same with OnPressed in button.
Step 1: Create Dialog
showAlertDialog(BuildContext context){
AlertDialog alert=AlertDialog(
content: new Row(
children: [
CircularProgressIndicator(),
Container(margin: EdgeInsets.only(left: 5),child:Text("Loading" )),
],),
);
showDialog(barrierDismissible: false,
context:context,
builder:(BuildContext context){
return alert;
},
);
}
Step 2: Call it
showAlertDialog(context);
await firebaseAuth.signInWithEmailAndPassword(email: email, password: password);
Navigator.pop(context);
Example Dialog and login form
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:firebase_auth/firebase_auth.dart';
class DynamicLayout extends StatefulWidget{
#override
State<StatefulWidget> createState() {
// TODO: implement createState
return new MyWidget();
}
}
showAlertDialog(BuildContext context){
AlertDialog alert=AlertDialog(
content: new Row(
children: [
CircularProgressIndicator(),
Container(margin: EdgeInsets.only(left: 5),child:Text("Loading" )),
],),
);
showDialog(barrierDismissible: false,
context:context,
builder:(BuildContext context){
return alert;
},
);
}
class MyWidget extends State<DynamicLayout>{
Color color = Colors.indigoAccent;
String title='app';
GlobalKey<FormState> globalKey=GlobalKey<FormState>();
String email,password;
login() async{
var currentState= globalKey.currentState;
if(currentState.validate()){
currentState.save();
FirebaseAuth firebaseAuth=FirebaseAuth.instance;
try {
showAlertDialog(context);
AuthResult authResult=await firebaseAuth.signInWithEmailAndPassword(
email: email, password: password);
FirebaseUser user=authResult.user;
Navigator.pop(context);
}catch(e){
print(e);
}
}else{
}
}
#override
Widget build(BuildContext context) {
return new Scaffold(
appBar:AppBar(
title: Text("$title"),
) ,
body: Container(child: Form(
key: globalKey,
child: Container(
padding: EdgeInsets.all(10),
child: Column(children: <Widget>[
TextFormField(decoration: InputDecoration(icon: Icon(Icons.email),labelText: 'Email'),
// ignore: missing_return
validator:(val){
if(val.isEmpty)
return 'Please Enter Your Email';
},
onSaved:(val){
email=val;
},
),
TextFormField(decoration: InputDecoration(icon: Icon(Icons.lock),labelText: 'Password'),
obscureText: true,
// ignore: missing_return
validator:(val){
if(val.isEmpty)
return 'Please Enter Your Password';
},
onSaved:(val){
password=val;
},
),
RaisedButton(color: Colors.lightBlue,textColor: Colors.white,child: Text('Login'),
onPressed:login),
],)
,),)
),
);
}
}
Example from Ui
1. Without plugin
class IndiSampleState extends State<ProgHudPage> {
#override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(
title: new Text('Demo'),
),
body: Center(
child: RaisedButton(
color: Colors.blueAccent,
child: Text('Login'),
onPressed: () async {
showDialog(
context: context,
builder: (BuildContext context) {
return Center(child: CircularProgressIndicator(),);
});
await loginAction();
Navigator.pop(context);
},
),
));
}
Future<bool> loginAction() async {
//replace the below line of code with your login request
await new Future.delayed(const Duration(seconds: 2));
return true;
}
}
2. With plugin
check this plugin progress_hud
add the dependency in the pubspec.yaml file
dev_dependencies:
progress_hud:
import the package
import 'package:progress_hud/progress_hud.dart';
Sample code is given below to show and hide the indicator
class ProgHudPage extends StatefulWidget {
#override
_ProgHudPageState createState() => _ProgHudPageState();
}
class _ProgHudPageState extends State<ProgHudPage> {
ProgressHUD _progressHUD;
#override
void initState() {
_progressHUD = new ProgressHUD(
backgroundColor: Colors.black12,
color: Colors.white,
containerColor: Colors.blue,
borderRadius: 5.0,
loading: false,
text: 'Loading...',
);
super.initState();
}
#override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(
title: new Text('ProgressHUD Demo'),
),
body: new Stack(
children: <Widget>[
_progressHUD,
new Positioned(
child: RaisedButton(
color: Colors.blueAccent,
child: Text('Login'),
onPressed: () async{
_progressHUD.state.show();
await loginAction();
_progressHUD.state.dismiss();
},
),
bottom: 30.0,
right: 10.0)
],
));
}
Future<bool> loginAction()async{
//replace the below line of code with your login request
await new Future.delayed(const Duration(seconds: 2));
return true;
}
}
I took the following approach, which uses a simple modal progress indicator widget that wraps whatever you want to make modal during an async call.
The example in the package also addresses how to handle form validation while making async calls to validate the form (see flutter/issues/9688 for details of this problem). For example, without leaving the form, this async form validation method can be used to validate a new user name against existing names in a database while signing up.
https://pub.dartlang.org/packages/modal_progress_hud
Here is the demo of the example provided with the package (with source code):
Example could be adapted to other modal progress indicator behaviour (like different animations, additional text in modal, etc..).
This is my solution with stack
import 'package:flutter/material.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'dart:async';
final themeColor = new Color(0xfff5a623);
final primaryColor = new Color(0xff203152);
final greyColor = new Color(0xffaeaeae);
final greyColor2 = new Color(0xffE8E8E8);
class LoadindScreen extends StatefulWidget {
LoadindScreen({Key key, this.title}) : super(key: key);
final String title;
#override
LoginScreenState createState() => new LoginScreenState();
}
class LoginScreenState extends State<LoadindScreen> {
SharedPreferences prefs;
bool isLoading = false;
Future<Null> handleSignIn() async {
setState(() {
isLoading = true;
});
prefs = await SharedPreferences.getInstance();
var isLoadingFuture = Future.delayed(const Duration(seconds: 3), () {
return false;
});
isLoadingFuture.then((response) {
setState(() {
isLoading = response;
});
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(
widget.title,
style: TextStyle(color: primaryColor, fontWeight: FontWeight.bold),
),
centerTitle: true,
),
body: Stack(
children: <Widget>[
Center(
child: FlatButton(
onPressed: handleSignIn,
child: Text(
'SIGN IN WITH GOOGLE',
style: TextStyle(fontSize: 16.0),
),
color: Color(0xffdd4b39),
highlightColor: Color(0xffff7f7f),
splashColor: Colors.transparent,
textColor: Colors.white,
padding: EdgeInsets.fromLTRB(30.0, 15.0, 30.0, 15.0)),
),
// Loading
Positioned(
child: isLoading
? Container(
child: Center(
child: CircularProgressIndicator(
valueColor: AlwaysStoppedAnimation<Color>(themeColor),
),
),
color: Colors.white.withOpacity(0.8),
)
: Container(),
),
],
));
}
}
You can do it for center transparent progress indicator
Future<Null> _submitDialog(BuildContext context) async {
return await showDialog<Null>(
context: context,
barrierDismissible: false,
builder: (BuildContext context) {
return SimpleDialog(
elevation: 0.0,
backgroundColor: Colors.transparent,
children: <Widget>[
Center(
child: CircularProgressIndicator(),
)
],
);
});
}
{
isloading? progressIos:Container()
progressIos(int i) {
return Container(
color: i == 1
? AppColors.liteBlack
: i == 2 ? AppColors.darkBlack : i == 3 ? AppColors.pinkBtn : '',
child: Center(child: CupertinoActivityIndicator()));
}
}
You can use FutureBuilder widget instead. This takes an argument which must be a Future. Then you can use a snapshot which is the state at the time being of the async call when loging in, once it ends the state of the async function return will be updated and the future builder will rebuild itself so you can then ask for the new state.
FutureBuilder(
future: myFutureFunction(),
builder: (context, AsyncSnapshot<List<item>> snapshot) {
if (!snapshot.hasData) {
return Center(
child: CircularProgressIndicator(),
);
} else {
//Send the user to the next page.
},
);
Here you have an example on how to build a Future
Future<void> myFutureFunction() async{
await callToApi();}
Centered on screen:
Column(
mainAxisAlignment: MainAxisAlignment.center,
mainAxisSize: MainAxisSize.max,
crossAxisAlignment: CrossAxisAlignment.start,
children: [
Row(
mainAxisAlignment: MainAxisAlignment.center,
mainAxisSize: MainAxisSize.max,
children: [CircularProgressIndicator()])
])
class Loader extends StatefulWidget {
#override
State createState() => LoaderState();
}
class LoaderState extends State<Loader> with SingleTickerProviderStateMixin {
AnimationController controller;
Animation<double> animation;
#override
void initState() {
super.initState();
controller = AnimationController(
duration: Duration(milliseconds: 1200), vsync: this);
animation = CurvedAnimation(parent: controller, curve: Curves.elasticOut);
animation.addListener(() {
this.setState(() {});
});
animation.addStatusListener((AnimationStatus status) {});
controller.repeat();
}
#override
void dispose() {
controller.dispose();
super.dispose();
}
#override
Widget build(BuildContext context) {
return Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Container(
color: Colors.blue,
height: 3.0,
width: animation.value * 100.0,
),
Padding(
padding: EdgeInsets.only(bottom: 5.0),
),
Container(
color: Colors.blue[300],
height: 3.0,
width: animation.value * 75.0,
),
Padding(
padding: EdgeInsets.only(bottom: 5.0),
),
Container(
color: Colors.blue,
height: 3.0,
width: animation.value * 50.0,
)
],
);
}
}
Expanded(
child: Padding(
padding:
EdgeInsets.only(left: 20.0, right: 5.0, top:20.0),
child: GestureDetector(
onTap: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => FirstScreen()));
},
child: Container(
alignment: Alignment.center,
height: 45.0,
decoration: BoxDecoration(
color: Color(0xFF1976D2),
borderRadius: BorderRadius.circular(9.0)),
child: Text('Login',
style: TextStyle(
fontSize: 20.0, color: Colors.white))),
),
),
),
For your case, maybe it can be done by using showing a modal with a circle indicator. But I recommend using a simple plugin https://pub.dev/packages/flutter_easyloading.
The installation supper easy. Just run this flutter pub add flutter_easyloading in your terminal
Put this in you main.dart app
import 'package:flutter/material.dart';
import 'package:kunjungi_dokter/pages/welcome.dart';
import 'package:flutter_easyloading/flutter_easyloading.dart'; // <- add this
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
#override
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
home: const Welcome(),
builder: EasyLoading.init(), // <- add this
);
}
}
To show the modal or the loading widget, in my case I show it in mya _login function in Login Screen:
import 'package:flutter_easyloading/flutter_easyloading.dart';
// ... other code
_login() async {
EasyLoading.show(status: 'loading...', maskType: EasyLoadingMaskType.black); // code to show modal with masking
var data = await LoginAPI.connectToAPI(
emailController.text, passwordController.text);
if (data.isError) {
EasyLoading.showError('Login Error: ' + data.message); // code to show modal without masking and auto close
} else {
await storage.write(key: 'token', value: data.token);
await storage.write(key: 'email', value: emailController.text);
EasyLoading.showSuccess('Login Success!'); // code to show modal without masking and auto close
Navigator.of(context)
.push(MaterialPageRoute(builder: ((context) => const Home())));
}
}
// ... other code
Tips, you can use this to close the modal:
EasyLoading.dismiss();
You will need a library for it
void onLoading() {
showDialog(
context: context,
barrierDismissible: false,
builder: (BuildContext context) {
return GFLoader(
type: GFLoaderType.android,
);
},
);
}
and then use this function where you need in code
onLoading;