Develop Reference

Can't solve problem with FloatingActionButton

I want the dialog to open when a button is clicked, but an error occurs due to BLoC. Previously, there was such an error with the class itself, but I successfully solved it, and in this case, the complexity already arises. I've already tried a couple of options but couldn't solve it. I tried to make the event in onPressed as a separate widget, and the same error did not work either.
home_page
class HomePage extends StatelessWidget {
final todoRepository = TodoRepository();
#override
Widget build(BuildContext context) {
// final TodoBloc todoBloc = context.read<TodoBloc>();
return BlocProvider<TodoBloc>(
create: (context) => TodoBloc(todoRepository),
child: Scaffold(
appBar: AppBar(
title: const Text('Flutter Todos'),
),
// floatingActionButton: FloatingActionButton(
// onPressed: () {
// // _addTodo(context);
// final newTodo = Todo(description: 'Todo 1');
// BlocProvider.of<TodoBloc>(context).add(CreateTodos(newTodo));
// },
// child: const Icon(Icons.add),
// ),
body: SingleChildScrollView(
child: Column(
// crossAxisAlignment: CrossAxisAlignment.center,
children: [
// ActionButton(),
TodoList(),
],
),
),
floatingActionButton: FloatingActionButton(
child: const Icon(Icons.add, size: 32, color: Colors.black),
onPressed: () {
// showAddTodoSheet(context);
// showAddTodoSheet(BuildContext context) {
final TodoBloc todoBloc = context.read<TodoBloc>();
final _todoDescriptionFromController = TextEditingController();
showModalBottomSheet(
context: context,
builder: (builder) {
return BlocBuilder<TodoBloc, TodoState>(
builder: (context, state) {
return Padding(
padding: EdgeInsets.only(
bottom: MediaQuery.of(context).viewInsets.bottom),
child: Container(
color: Colors.transparent,
child: Container(
height: 230,
decoration: const BoxDecoration(
color: Colors.white,
borderRadius: BorderRadius.only(
topLeft: Radius.circular(10.0),
topRight: Radius.circular(10.0))),
child: Padding(
padding: const EdgeInsets.only(
left: 15, top: 25.0, right: 15, bottom: 30),
child: ListView(
children: <Widget>[
Row(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment:
CrossAxisAlignment.center,
children: <Widget>[
Expanded(
child: TextFormField(
controller:
_todoDescriptionFromController,
textInputAction:
TextInputAction.newline,
maxLines: 4,
style: const TextStyle(
fontSize: 21,
fontWeight: FontWeight.w400),
autofocus: true,
decoration: const InputDecoration(
hintText: 'I have to...',
labelText: 'New Todo',
labelStyle: TextStyle(
color: Colors.indigoAccent,
fontWeight: FontWeight.w500)),
validator: (value) {
if (value!.isEmpty) {
return 'Empty description!';
}
return value.contains('')
? 'Do not use the # char.'
: null;
},
),
),
Padding(
padding: const EdgeInsets.only(
left: 5, top: 15),
child: CircleAvatar(
backgroundColor: Colors.indigoAccent,
radius: 18,
child: IconButton(
icon: const Icon(
Icons.save,
size: 22,
color: Colors.white,
),
onPressed: () {
final newTodo = Todo(
description:
_todoDescriptionFromController
.value.text);
if (newTodo
.description.isNotEmpty) {
todoBloc
.add(CreateTodos(newTodo));
Navigator.pop(context);
}
},
),
),
)
],
),
],
),
),
),
),
);
});
});
},
),
));
}

You have to use MultiBlocProvider before MaterialApp.
just do like that
#override
Widget build(BuildContext context) => MultiBlocProvider(
providers: [
BlocProvider(create: (_) => TodoBloc()),
],
child: MaterialApp()
);

Red Screen Error type 'String' is not a subtype of type 'int' of 'index' Flutter

When I navigate my chat page, I see this error in red screen on emulator.
No idea why it does not work. Does anyone know how to solve it?
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:flutter/material.dart';
import '../chat/chat.dart';
class ChatHome extends StatefulWidget {
#override
_ChatHomeState createState() => _ChatHomeState();
}
class _ChatHomeState extends State<ChatHome> {
var _db = FirebaseFirestore.instance;
TextEditingController userController;
final _scaffKey = GlobalKey<ScaffoldState>();
#override
void initState() {
super.initState();
userController = new TextEditingController();
setState(() {});
}
#override
Widget build(BuildContext context) {
return Scaffold(
key: _scaffKey,
floatingActionButton: FloatingActionButton(
onPressed: () {
showDialog(
// barrierDismissible: false,
context: context,
builder: (context) => _buildPopUpMessage(context),
);
},
splashColor: Theme.of(context).colorScheme.onSecondary,
child: Icon(
Icons.add,
),
),
body: FutureBuilder(
future: getPosts(),
builder: (_, snapshot) {
if (snapshot.hasData) {
String myId = snapshot.data['id'];
return StreamBuilder(
stream: getChats(myId),
builder: (context, snapshot) {
if (snapshot.hasData) {
QuerySnapshot qSnap = snapshot.data;
List<DocumentSnapshot> docs = qSnap.docs;
if (docs.length == 0)
return Center(
child: Text('No Chats yet!'),
);
return ListView.builder(
itemCount: docs.length,
itemBuilder: (context, index) {
List<dynamic> members = docs[index].data()['members'];
String userId;
userId = members.elementAt(0) == myId
? members.elementAt(1)
: members.elementAt(0);
return FutureBuilder(
future: getUserByUsername(userId),
builder: (context, _snapshot) {
if (_snapshot.hasData) {
DocumentSnapshot docSnapUser = _snapshot.data;
Map<String, dynamic> _user = docSnapUser.data();
return Card(
margin: EdgeInsets.all(8.0),
elevation: 8.0,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(5.0),
),
child: InkWell(
splashColor:
Theme.of(context).colorScheme.primary,
onTap: () => Navigator.push(
context,
MaterialPageRoute(
builder: (context) => Chat(
peerId: _user["id"],
peerAvatar: _user['photoUrl'],
))),
child: Container(
margin: EdgeInsets.all(10.0),
height:
MediaQuery.of(context).size.height * 0.08,
child: Center(
child: Row(
children: [
Hero(
tag: _user['photoUrl'],
child: Container(
width: MediaQuery.of(context)
.size
.width *
0.15,
height: MediaQuery.of(context)
.size
.width *
0.15,
decoration: new BoxDecoration(
shape: BoxShape.circle,
image: new DecorationImage(
fit: BoxFit.cover,
image: new NetworkImage(
_user['photoUrl']),
),
),
),
),
SizedBox(
width: MediaQuery.of(context)
.size
.width *
0.02,
),
SizedBox(
width: MediaQuery.of(context)
.size
.width *
0.43,
child: Text(
_user['nickname'],
style: TextStyle(
fontSize: 16,
fontWeight: FontWeight.w600,
),
),
),
],
),
),
),
),
);
}
return Card(
margin: EdgeInsets.all(8.0),
elevation: 8.0,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(5.0),
),
child: Container(
margin: EdgeInsets.all(10.0),
height: MediaQuery.of(context).size.height * 0.08,
child: Center(
child: CircularProgressIndicator(
valueColor: new AlwaysStoppedAnimation(
Theme.of(context).colorScheme.primary,
),
),
),
),
);
},
);
},
);
}
return Center(
child: CircularProgressIndicator(
valueColor: new AlwaysStoppedAnimation(
Theme.of(context).colorScheme.primary,
),
),
);
},
);
}
return Center(
child: CircularProgressIndicator(
valueColor: new AlwaysStoppedAnimation(
Theme.of(context).colorScheme.primary,
),
),
);
},
),
);
}
Widget _timeDivider(Timestamp time) {
DateTime t = time.toDate();
String minute =
t.minute > 9 ? t.minute.toString() : '0' + t.minute.toString();
String ampm = t.hour >= 12 ? "PM" : "AM";
int hour = t.hour >= 12 ? t.hour % 12 : t.hour;
DateTime press = DateTime.now();
if (press.year == t.year && press.month == t.month && press.day == t.day)
return Text(hour.toString() + ':' + minute + ' ' + ampm);
return Text(t.day.toString() +
'/' +
(t.month + 1).toString() +
'/' +
t.year.toString());
}
Widget _buildPopUpMessage(context) {
return Align(
alignment: Alignment.topCenter,
child: Container(
padding: EdgeInsets.all(8.0),
height: MediaQuery.of(context).size.width * .5,
width: MediaQuery.of(context).size.width * .6,
decoration: BoxDecoration(
color: Colors.white,
borderRadius: BorderRadius.circular(40),
),
margin: EdgeInsets.only(bottom: 50, left: 12, right: 12, top: 50),
child: SingleChildScrollView(
child: Column(
children: <Widget>[
SizedBox(
height: MediaQuery.of(context).size.width * .1,
child: Center(
child: new RichText(
text: new TextSpan(
style: new TextStyle(
fontSize: 14.0,
color: Colors.black,
),
children: <TextSpan>[
new TextSpan(
text: 'username',
style: new TextStyle(
color: Theme.of(context).colorScheme.primary,
fontWeight: FontWeight.bold),
),
new TextSpan(
text: '#gmail.com',
),
],
),
),
),
),
SizedBox(
height: MediaQuery.of(context).size.width * .2,
child: Center(
child: Padding(
padding: const EdgeInsets.all(8.0),
child: Material(
child: TextField(
autofocus: true,
controller: userController,
decoration: new InputDecoration(
border: new OutlineInputBorder(
borderSide: BorderSide(
color: Theme.of(context).colorScheme.primary,
),
borderRadius: const BorderRadius.all(
const Radius.circular(10.0),
),
),
focusedBorder: new OutlineInputBorder(
borderSide: BorderSide(
color: Theme.of(context).colorScheme.primary,
),
borderRadius: const BorderRadius.all(
const Radius.circular(10.0),
),
),
enabledBorder: new OutlineInputBorder(
borderSide: BorderSide(
color: Theme.of(context).colorScheme.primary,
),
borderRadius: const BorderRadius.all(
const Radius.circular(10.0),
),
),
errorBorder: new OutlineInputBorder(
borderSide: BorderSide(
color: Theme.of(context).colorScheme.error,
),
borderRadius: const BorderRadius.all(
const Radius.circular(10.0),
),
),
filled: true,
hintText: "Type in only Username",
hintStyle: TextStyle(fontSize: 16.0),
),
),
),
),
),
),
SizedBox(
height: MediaQuery.of(context).size.width * .1,
child: Center(
child: Align(
alignment: Alignment.center,
child: RaisedButton(
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(18.0),
),
color: Theme.of(context).colorScheme.secondary,
child: Text(
'Let\'s chat with your friend.',
style: TextStyle(
color: Theme.of(context).colorScheme.onSecondary),
),
onPressed: () async {
if (userController.text.isNotEmpty) {
String username = userController.text.toString();
userController.clear();
QuerySnapshot doc =
getUserByEmail(username + '#gmail.com');
if (doc.docs.length != 0) {
DocumentSnapshot user = doc.docs[0];
Map<String, dynamic> userData = user.data();
Navigator.pop(context);
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => Chat(
peerId: userData["id"],
peerAvatar: userData['photoUrl'],
)));
print(user.data()['nickname'].toString());
} else {
showSnackPlz(context, username);
Navigator.pop(context);
}
} else {
showSnackPlzWithMessage(context, 'Empty Username');
Navigator.pop(context);
}
},
),
),
),
),
],
),
),
),
);
}
showSnackPlz(BuildContext context, String username) {
final SnackBar snackMe = SnackBar(
content: new RichText(
text: new TextSpan(
style: new TextStyle(
fontSize: 14.0,
),
children: <TextSpan>[
new TextSpan(
text: 'User with email ',
),
new TextSpan(
text: username,
style: new TextStyle(fontWeight: FontWeight.bold),
),
new TextSpan(
text: '#gmail.com not in the database!',
),
],
),
),
);
_scaffKey.currentState.showSnackBar(snackMe);
}
showSnackPlzWithMessage(BuildContext context, String message) {
final SnackBar snackMe = SnackBar(
content: new Text(message),
);
_scaffKey.currentState.showSnackBar(snackMe);
}
getChats(String uid) {
return FirebaseFirestore.instance
.collection('messages')
.where('members', arrayContains: uid)
.snapshots();
}
getUserByUsername(String username) async {
return await _db.collection('users').doc(username).get();
}
getUserByEmail(String email) async {
return await _db.collection('users').where('email', isEqualTo: email).get();
}
Future getPosts() async {
var firestore = FirebaseFirestore.instance;
QuerySnapshot qn = await firestore.collection('users').get();
return qn.docs;
}
}
Can't find which code-row causes this.
Tried many changes but nothing helped.
Screenshot of the error
I've been facing this problem for whole day. Being rookie in flutterworld sometimes take bunch of time.

I can only assume what the problem could be please send the logs... So
List<dynamic> members = docs[index].data()['members'];
String userId;
userId = members.elementAt(0) == myId
? members.elementAt(1)
: members.elementAt(0);
You are using this to get the userId (String) from a dynamic list.
check whether you dynamic list only contains String values before handling a value as a string. Please do this for all other occurrences of dynamic...
This error means that you cast an int to a string. That is illegal. Just check all your String occurrences.

Flutter - put variable value outside a function

i'm trying to show the data i retrieve on a function outside of it (to show in a listview of products) but i cant do it because i cant access the variable.
First I open a dialog where i put the order number, when i click a button on this dialog it runs the following code:
(this function is inside a onPressed).
Future loadProdutos() async{
ProdutosList produtosList =
ProdutosList.fromJson(response.data);
print(produtosList.produtos[1].qtd);
print(produtosList.produtos.length);
}
setState(() {
loadProdutos();
Navigator.pop(context, true);
});
So the data its stored on produtoslist, but when I try to use the produtosList length on the listview (for example) like the example below it cant access the data.
Here
child: ListView.builder(
itemCount: produtosList.produtos.length, <<< //Undefined name 'produtosList'.
Try correcting the name to one that is defined, or defining the name.dart(undefined_identifi
How can I make produtosList accessable from the whole file?
Or to create it outside of the function and use it inside (when i try i cant access the variable inside of the function, maybe because its async).
Heres the full code
class OS extends StatefulWidget {
#override
_OSState createState() => _OSState();
}
class _OSState extends State<OS> {
static _read() async {
final prefs = await SharedPreferences.getInstance();
final key = 'operador';
final value = prefs.getString(key);
print('saved tester $value');
String operadorLogado = value;
return operadorLogado;
}
#override
final _numeroOsController = TextEditingController();
void initState() {
super.initState();
_read();
var produtosList1 = <ProdutoOs>[];
//WidgetsBinding.instance.addPostFrameCallback((_) => _read());
// final prefs = await SharedPreferences.getInstance();
// final key = 'usuario';
// final value = prefs.getString(key);
// print('saved $value');
}
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("OS Nº xxx"),
actions: <Widget>[
Padding(
padding: EdgeInsets.only(right: 20.0),
child: GestureDetector(
onTap: () {
showDialog(
context: context,
builder: (BuildContext context) {
return AlertDialog(
scrollable: true,
title: Text('BUSCAR OS'),
content: Padding(
padding: const EdgeInsets.all(8.0),
child: Form(
child: TextFormField(
controller: _numeroOsController,
decoration: InputDecoration(
icon: Icon(Icons.search),
),
),
),
),
actions: [
ElevatedButton(
style: ElevatedButton.styleFrom(
primary: Colors.blue,
onPrimary: Colors.white,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(32.0),
),
),
child: Text("IR"),
onPressed: () async {
Response response;
Dio dio = new Dio();
String url =
'http://192.168.15.2:8090/api/getOs';
response = await dio.post(url, data: {
"numeroos": _numeroOsController.text
});
print(response.statusCode);
jsonDecode(response);
Future loadProdutos() async {
ProdutosList produtosList =
ProdutosList.fromJson(response.data);
print(produtosList.produtos[1].qtd);
print(produtosList.produtos.length);
}
setState(() {
loadProdutos();
Navigator.pop(context, true);
});
},
)
]);
});
},
child: Icon(
Icons.search,
size: 26.0,
),
)),
],
),
body: Column(
children: [
Container(
color: Colors.blue,
child: Padding(
padding: const EdgeInsets.only(top: 8.0),
child: Row(
children: [
Expanded(
flex: 8,
child: Text(
"CLIENTE:",
style: TextStyle(color: Colors.white),
),
),
Expanded(
flex: 8,
child: Text(
"STATUS:",
style: TextStyle(color: Colors.white),
),
),
],
),
),
),
Container(
color: Colors.blue,
child: Padding(
padding: const EdgeInsets.fromLTRB(0, 8.0, 0, 8.0),
child: Row(
children: <Widget>[
Expanded(
flex: 2,
child: Text("CÓDIGO",
style: TextStyle(fontWeight: FontWeight.bold),
overflow: TextOverflow.ellipsis),
),
Expanded(
flex: 1,
child: Text(
"QTD",
style: TextStyle(fontWeight: FontWeight.bold),
),
),
Expanded(
flex: 3,
child: Text(
"FUNCIONÁRIO",
style: TextStyle(fontWeight: FontWeight.bold),
),
),
Expanded(
flex: 4,
child: Text(
"DESCRIÇÃO",
style: TextStyle(fontWeight: FontWeight.bold),
),
),
],
),
),
),
Divider(
height: 5.0,
),
Expanded(
child: ListView.builder(
itemCount: 3,
itemBuilder: (context, index) {
return Padding(
padding: const EdgeInsets.fromLTRB(0.0, 4.0, 0.0, 4.0),
child: Row(
children: <Widget>[
Expanded(
flex: 2,
child: Text(
"12345",
style: TextStyle(fontWeight: FontWeight.bold),
),
),
Expanded(
flex: 1,
child: Text(
"12",
style: TextStyle(fontWeight: FontWeight.bold),
),
),
Expanded(
flex: 3,
child: Text("example",
style: TextStyle(fontWeight: FontWeight.bold),
overflow: TextOverflow.ellipsis
),
),
Expanded(
flex: 4,
child: Text(
"DESCRIÇÃO DA PEÇA XXXXXX11111111 XXXXXXX",
style: TextStyle(fontWeight: FontWeight.bold),
overflow: TextOverflow.ellipsis),
),
],
),
);
}),
)
],
),
floatingActionButton: FloatingActionButton(
onPressed: () {
showDialog(
context: context,
builder: (BuildContext context) {
return AlertDialog(
scrollable: true,
title: Text('ADICIONAR PEÇA'),
content: Padding(
padding: const EdgeInsets.all(8.0),
child: Form(
child: Column(
children: <Widget>[
TextFormField(
decoration: InputDecoration(
icon: Icon(Icons.search),
),
),
],
),
),
),
actions: [
ElevatedButton(
style: ElevatedButton.styleFrom(
primary: Colors.blue,
onPrimary: Colors.white,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(32.0),
),
),
child: Text("IR"),
onPressed: () {
// your code
}),
],
);
});
},
child: Icon(Icons.add)),
);
}
}

Declare a local variable in class.
For example:
class PhotosScreen {
final photos = <Photo>[];
Future<void> reloadPhotos() async {
photos.clear();
photos.addAll(await api.getPhotos());
setState(() {});
}
}
In your case (you placed a variable to method, not to class):
var produtosList1 = <ProdutoOs>[];
#override
final _numeroOsController = TextEditingController();
void initState() {
super.initState();
}

Flutter : How to prevent rebuild of whole Reorderable Listview?

Currently I'm using flutter package 'Reorderables' to show a reorderable listview which contains several images.These images can be deleted from listview through a button , everything works fine. But the listview rebuild everytime when I delete an image. I'm using a class called 'ReorderableListviewManager' with ChangeNotifier to update images and Provider.of<ReorderableListviewManager>(context) to get latest images . The problem now is that using Provider.of<ReorderableListviewManager>(context) makes build() called everytime I delete an image , so the listview rebuid. I koow I
can use consumer to only rebuild part of widget tree, but it seems like that there's no place to put consumer in children of this Listview. Is there a way to rebuild only image but not whole ReorderableListview ? Thanks very much!
Below is my code:
class NotePicturesEditScreen extends StatefulWidget {
final List<Page> notePictures;
final NotePicturesEditBloc bloc;
NotePicturesEditScreen({#required this.notePictures, #required this.bloc});
static Widget create(BuildContext context, List<Page> notePictures) {
return Provider<NotePicturesEditBloc>(
create: (context) => NotePicturesEditBloc(),
child: Consumer<NotePicturesEditBloc>(
builder: (context, bloc, _) =>
ChangeNotifierProvider<ReorderableListviewManager>(
create: (context) => ReorderableListviewManager(),
child: NotePicturesEditScreen(
bloc: bloc,
notePictures: notePictures,
),
)),
dispose: (context, bloc) => bloc.dispose(),
);
}
#override
_NotePicturesEditScreenState createState() => _NotePicturesEditScreenState();
}
class _NotePicturesEditScreenState extends State<NotePicturesEditScreen> {
PreloadPageController _pageController;
ScrollController _reorderableScrollController;
List<Page> notePicturesCopy;
int longPressIndex;
List<double> smallImagesWidth;
double scrollOffset = 0;
_reorderableScrollListener() {
scrollOffset = _reorderableScrollController.offset;
}
#override
void initState() {
Provider.of<ReorderableListviewManager>(context, listen: false)
.notePictures = widget.notePictures;
notePicturesCopy = widget.notePictures;
_reorderableScrollController = ScrollController();
_pageController = PreloadPageController();
_reorderableScrollController.addListener(_reorderableScrollListener);
Provider.of<ReorderableListviewManager>(context, listen: false)
.getSmallImagesWidth(notePicturesCopy, context)
.then((imagesWidth) {
smallImagesWidth = imagesWidth;
});
super.initState();
}
#override
void dispose() {
_pageController.dispose();
_reorderableScrollController.dispose();
super.dispose();
}
#override
Widget build(BuildContext context) {
ReorderableListviewManager reorderableManager =
Provider.of<ReorderableListviewManager>(context, listen: false);
return SafeArea(
child: Scaffold(
appBar: AppBar(
backgroundColor: Colors.white,
shape: Border(bottom: BorderSide(color: Colors.black12)),
iconTheme: IconThemeData(color: Colors.black87),
elevation: 0,
automaticallyImplyLeading: false,
titleSpacing: 0,
centerTitle: true,
title: Row(
mainAxisAlignment: MainAxisAlignment.start,
crossAxisAlignment: CrossAxisAlignment.center,
children: <Widget>[
Container(
child: IconButton(
padding: EdgeInsets.only(left: 20, right: 12),
onPressed: () => Navigator.of(context).pop(),
icon: Icon(Icons.close),
),
),
Text('編輯',
style: TextStyle(color: Colors.black87, fontSize: 18))
],
),
actions: <Widget>[
FlatButton(
onPressed: () {},
child: Text(
'下一步',
),
)
],
),
backgroundColor: Color(0xffeeeeee),
body: Column(
mainAxisAlignment: MainAxisAlignment.start,
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Spacer(),
StreamBuilder<List<Page>>(
initialData: widget.notePictures,
stream: widget.bloc.notePicturesStream,
builder: (context, snapshot) {
notePicturesCopy = snapshot.data;
return Container(
margin: EdgeInsets.symmetric(horizontal: 20),
height: MediaQuery.of(context).size.height * 0.65,
child: PreloadPageView.builder(
preloadPagesCount: snapshot.data.length,
controller: _pageController,
itemCount: snapshot.data.length,
onPageChanged: (index) {
reorderableManager.updateCurrentIndex(index);
reorderableManager.scrollToCenter(
smallImagesWidth,
index,
scrollOffset,
_reorderableScrollController,
context);
},
itemBuilder: (context, index) {
return Container(
child: Image.memory(
File.fromUri(
snapshot.data[index].polygon.isNotEmpty
? snapshot.data[index]
.documentPreviewImageFileUri
: snapshot.data[index]
.originalPreviewImageFileUri)
.readAsBytesSync(),
gaplessPlayback: true,
alignment: Alignment.center,
),
);
}),
);
},
),
Spacer(),
Container(
height: MediaQuery.of(context).size.height * 0.1,
margin: EdgeInsets.symmetric(horizontal: 20),
child: SingleChildScrollView(
scrollDirection: Axis.horizontal,
child: ReorderableRow(
scrollController: _reorderableScrollController,
buildDraggableFeedback: (context, constraints, __) =>
Container(
width: constraints.maxWidth,
height: constraints.maxHeight,
child: Image.memory(File.fromUri(
notePicturesCopy[longPressIndex]
.polygon
.isNotEmpty
? notePicturesCopy[longPressIndex]
.documentPreviewImageFileUri
: notePicturesCopy[longPressIndex]
.originalPreviewImageFileUri)
.readAsBytesSync()),
),
onReorder: (oldIndex, newIndex) async {
List<Page> result = await widget.bloc.reorderPictures(
oldIndex,
newIndex,
reorderableManager.notePictures);
_pageController.jumpToPage(newIndex);
reorderableManager.updateNotePictures(result);
reorderableManager
.getSmallImagesWidth(result, context)
.then((imagesWidth) {
smallImagesWidth = imagesWidth;
});
},
footer: Container(
width: 32,
height: 32,
margin: EdgeInsets.only(left: 16),
child: SizedBox(
child: FloatingActionButton(
backgroundColor: Colors.white,
elevation: 1,
disabledElevation: 0,
highlightElevation: 1,
child: Icon(Icons.add, color: Colors.blueAccent),
onPressed: notePicturesCopy.length >= 20
? () {
Scaffold.of(context)
.showSnackBar(SnackBar(
content: Text('筆記上限為20頁 !'),
));
}
: () async {
List<Page> notePictures =
await widget.bloc.addPicture(
reorderableManager.notePictures);
List<double> imagesWidth =
await reorderableManager
.getSmallImagesWidth(
notePictures, context);
smallImagesWidth = imagesWidth;
reorderableManager.updateCurrentIndex(
notePictures.length - 1);
reorderableManager
.updateNotePictures(notePictures);
_pageController
.jumpToPage(notePictures.length - 1);
},
),
),
),
children: Provider.of<ReorderableListviewManager>(
context)
.notePictures
.asMap()
.map((index, page) {
return MapEntry(
index,
Consumer<ReorderableListviewManager>(
key: ValueKey('value$index'),
builder: (context, manager, _) =>
GestureDetector(
onTapDown: (_) {
longPressIndex = index;
},
onTap: () {
reorderableManager.scrollToCenter(
smallImagesWidth,
index,
scrollOffset,
_reorderableScrollController,
context);
_pageController.jumpToPage(index);
},
child: Container(
margin: EdgeInsets.only(
left: index == 0 ? 0 : 12),
decoration: BoxDecoration(
border: Border.all(
width: 1.5,
color: index ==
manager
.getCurrentIndex
? Colors.blueAccent
: Colors.transparent)),
child: index + 1 <=
manager.notePictures.length
? Image.memory(
File.fromUri(manager
.notePictures[
index]
.polygon
.isNotEmpty
? manager
.notePictures[
index]
.documentPreviewImageFileUri
: manager
.notePictures[
index]
.originalPreviewImageFileUri)
.readAsBytesSync(),
gaplessPlayback: true,
)
: null),
),
));
})
.values
.toList()),
)),
Spacer(),
Container(
decoration: BoxDecoration(
color: Colors.white,
border: Border(top: BorderSide(color: Colors.black12))),
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: <Widget>[
FlatButton(
onPressed: () async => await widget.bloc
.cropNotePicture(reorderableManager.notePictures,
_pageController.page.round())
.then((notePictures) {
reorderableManager.updateNotePictures(notePictures);
reorderableManager
.getSmallImagesWidth(notePictures, context)
.then((imagesWidth) {
smallImagesWidth = imagesWidth;
});
}),
child: Column(
children: <Widget>[
Icon(
Icons.crop,
color: Colors.blueAccent,
),
Container(
margin: EdgeInsets.only(top: 1),
child: Text(
'裁切',
style: TextStyle(color: Colors.blueAccent),
),
)
],
),
),
FlatButton(
onPressed: () {
int deleteIndex = _pageController.page.round();
widget.bloc
.deletePicture(
reorderableManager.notePictures, deleteIndex)
.then((notePictures) {
if (deleteIndex == notePictures.length) {
reorderableManager
.updateCurrentIndex(notePictures.length - 1);
}
reorderableManager.updateNotePictures(notePictures);
reorderableManager
.getSmallImagesWidth(notePictures, context)
.then((imagesWidth) {
smallImagesWidth = imagesWidth;
});
if (reorderableManager.notePictures.length == 0) {
Navigator.pop(context);
}
});
},
child: Column(
children: <Widget>[
Icon(
Icons.delete_outline,
color: Colors.blueAccent,
),
Container(
margin: EdgeInsets.only(top: 1),
child: Text(
'刪除',
style: TextStyle(color: Colors.blueAccent),
),
),
],
),
)
],
),
)
],
)),
);
}
}

You can't prevent a rebuild on your ReorderableListView widget because it will be rebuild every time there's an update on the Provider. What you can do here is to keep track the current index of all visible ListView items. When new data should be displayed coming from the Provider, you can retain the current indices of previous ListView items, and add the newly added items at the end of the list, or wherever you like.

Screen is not closing on click on press of alert dialog in flutter

Hi I have designed a screen in flutter. I have AlertDialog on which I want to close the dialog and screen on pressing. Right now AlertDialog dismiss on press but screen is not closing.
Does anyone know how to do this ?
class ForgotPasswordScreen extends StatefulWidget {
#override
State<StatefulWidget> createState() {
return ForgotPasswordScreenState();
}
}
class ForgotPasswordScreenState extends State<ForgotPasswordScreen> {
var emailController = new TextEditingController();
var authHandler = new Auth();
bool isLoading = false;
#override
Widget build(BuildContext context) {
return new Scaffold(
body: Container(
height: MediaQuery.of(context).size.height,
decoration: BoxDecoration(
color: Colors.white,
),
child: new Column(
crossAxisAlignment: CrossAxisAlignment.center,
mainAxisSize: MainAxisSize.max,
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
new Row(
children: <Widget>[
new Expanded(
child: isLoading
? Center(child: CircularProgressIndicator())
: new Container()),
],
),
new Row(
children: <Widget>[
new Expanded(
child: new Padding(
padding: const EdgeInsets.only(left: 40.0),
child: new Text(
"EMAIL",
style: TextStyle(
fontWeight: FontWeight.bold,
color: Colors.redAccent,
fontSize: 15.0,
),
),
),
),
],
),
new Container(
width: MediaQuery.of(context).size.width,
margin:
const EdgeInsets.only(left: 40.0, right: 40.0, top: 10.0),
alignment: Alignment.center,
decoration: BoxDecoration(
border: Border(
bottom: BorderSide(
color: Colors.redAccent,
width: 0.5,
style: BorderStyle.solid),
),
),
padding: const EdgeInsets.only(left: 0.0, right: 10.0),
child: new Row(
crossAxisAlignment: CrossAxisAlignment.center,
mainAxisAlignment: MainAxisAlignment.start,
children: <Widget>[
new Expanded(
child: TextField(
controller: emailController,
textAlign: TextAlign.left,
decoration: InputDecoration(
border: InputBorder.none,
hintText: 'PLEASE ENTER YOUR EMAIL',
hintStyle: TextStyle(color: Colors.grey),
),
),
),
],
),
),
Divider(
height: 24.0,
),
new Container(
width: MediaQuery.of(context).size.width,
margin:
const EdgeInsets.only(left: 30.0, right: 30.0, top: 20.0),
alignment: Alignment.center,
child: new Row(
children: <Widget>[
new Expanded(
child: new FlatButton(
shape: new RoundedRectangleBorder(
borderRadius: new BorderRadius.circular(30.0),
),
color: Colors.redAccent,
onPressed: () {
setState(() {
isLoading = true;
});
authHandler
.sendPasswordResetEmail(emailController.text)
.then((void nothing) {
showDialog(
context: context,
builder: (BuildContext context) {
// return object of type Dialog
return AlertDialog(
content: new Text(
"Password reset email has been sent."),
actions: <Widget>[
// usually buttons at the bottom of the dialog
new FlatButton(
child: new Text("OK"),
onPressed: () {
Navigator.pop(context);
},
),
],
);
},
);
setState(() {
isLoading = false;
});
}).catchError((e) => print(e));
},
child: new Container(
padding: const EdgeInsets.symmetric(
vertical: 20.0,
horizontal: 20.0,
),
child: new Row(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
new Expanded(
child: Text(
"FORGOT PASSWORD",
textAlign: TextAlign.center,
style: TextStyle(
color: Colors.white,
fontWeight: FontWeight.bold),
),
),
],
),
),
),
),
],
),
),
],
)));
}
}

Ideally, you'll want to call pop more than once. One for the modal, another for the actual route.
There are a few ways to achieve this. But ideally you'll want to await the close of the dialog before triggering another close:
foo() async {
await showDialog(
context: context,
builder: (context) => AlertDialog(
actions: [
new FlatButton(
child: new Text("OK"),
onPressed: () => Navigator.pop(context),
),
],
),
);
Navigator.pop(context);
}
This way, both the route and the modal can handle their close however they like.

This is how i did with mine
bool _logout = false;
and then at the start of build Widget
#override
Widget build(BuildContext context) {
return WillPopScope(
onWillPop: () async {
_onBackPressed(context);
return _logout;
},
child: Container(),
);
}
and the method _onBackPressed returns a custom dialog Class like so
void _onBackPressed(BuildContext c) async {
await showDialog(
barrierColor: CustomColors.darkGrey.withOpacity(0.8),
barrierDismissible: true,
context: context,
builder: (BuildContext context) {
return CustomDialogBox(
title: 'Logout',
description: 'Are you sure you want to logout?',
rightButtonText: 'Yes',
onPClick: () {
_logout = true;
if (_logout == true) {
Get.back();
}
},
onNClick: () {
_logout = false;
Get.back();
},
);
});
if (_logout == true) {
Get.back();
}
}
and my custom Dialog class is here
class CustomDialogBox extends StatefulWidget {
final String? title, description, leftButtonText, rightButtonText;
final VoidCallback? onPClick, onNClick;
final Image? image;
const CustomDialogBox({
Key? key,
this.title,
this.description,
this.leftButtonText,
this.rightButtonText,
this.image,
this.onPClick,
this.onNClick,
}) : super(key: key);
#override
_CustomDialogBoxState createState() =>
// ignore: no_logic_in_create_state
_CustomDialogBoxState(onPClick!, onNClick!);
}
class _CustomDialogBoxState extends State<CustomDialogBox> {
final VoidCallback onPClick, onNClick;
_CustomDialogBoxState(this.onPClick, this.onNClick);
#override
Widget build(BuildContext context) {
return Dialog(
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(Dimensions.BORDER_RADIUS_4),
),
elevation: 0,
backgroundColor: Colors.transparent,
child: Container(
//height: 200,
padding: const EdgeInsets.only(
left: 10,
right: 0,
bottom: 10,
),
decoration: BoxDecoration(
shape: BoxShape.rectangle,
color: Colors.white,
borderRadius: BorderRadius.circular(8),
boxShadow: [
BoxShadow(
color: CustomColors.darkGrey,
offset: const Offset(0, 30),
blurRadius: 20,
),
]),
child: Wrap(children: <Widget>[
dialogBody(context),
]),
),
);
}
Widget dialogBody(context) {
return Column(children: [
Row(mainAxisAlignment: MainAxisAlignment.spaceBetween, children: [
Image.asset(
Images.LOGO,
height: MediaQuery.of(context).size.height * 0.035,
),
IconButton(
//padding: const EdgeInsets.all(0),
onPressed: () {
Get.back();
},
icon: const CircleAvatar(
radius: 12.5,
child: Icon(
Icons.close,
color: Colors.white,
),
backgroundColor: Colors.red,
),
),
]),
Padding(
padding: const EdgeInsets.only(
right: 10,
),
child: Column(children: [
//----//
customText(
text: widget.title ?? '',
fontFamily: 'black',
fontSize: 16,
),
//----//
const Space(0, 0.01),
//----//
customText(
text: widget.description ?? '',
fontSize: 14,
),
]),
),
//----//
const Space(0, 0.03),
//----//
Padding(
padding: const EdgeInsets.only(
right: 10,
),
child:
Row(mainAxisAlignment: MainAxisAlignment.spaceBetween, children: [
//----//
raisedButton(
text: widget.leftButtonText ?? 'Cancel',
fontFamily: 'roman',
height: 35,
width: 105,
buttonColor: CustomColors.red,
onClick: () {
return onNClick();
},
context: context,
),
//----//
raisedButton(
text: widget.rightButtonText ?? 'Okay',
fontFamily: 'roman',
height: 35,
width: 105,
buttonColor: CustomColors.green,
onClick: () {
return onPClick();
},
context: context,
),
//----//
]),
),
]);
}
}
the buttons and texts are custom so feel free to change them. and where you see Get.back(); is GetX code.. you can replace with Navigator.of(context).pop();

try this
showPop() async {
await showDialog(
context: context,
barrierDismissible: true,
builder: (context) => AlertDialog(
actions: [
new FlatButton(
child: new Text("Close"),
onPressed: () => Navigator.pop(context),
),
],
),
);
}