I want to create a list of entries the user makes, add that list to a list of lists . but each time I add a new list, all the sublists are updated to the new one
import 'package:flutter/material.dart';
import 'package:fooderlichapp/themes/models.dart';
class Display extends StatelessWidget {
final TextEditingController
textCont = TextEditingController();
void add(list) {
list.add(textCont.text); }
void addModelClass(list, model) {
model = Model(name: textCont.text, list: list);
ModelClass.modelList.add(model); }
void view() {
var models = ModelClass.modelList;
for (var model in models) {
debugPrint(" ${model.list}");
} }
#override Widget build(BuildContext context) {
List<String> list = [];
var model = Model(name: textCont.text, list: list);
return Container(
child: Scaffold(
body: Column(
children: [
TextField(
controller: textCont,
),
IconButton(
onPressed: () {
add(list);
debugPrint("added text successfully");
},
icon: Icon(Icons.add)),
TextButton(
onPressed: () {
addModelClass(list, model);
},
child: Text("add text")),
ElevatedButton(
onPressed: () {
view();
},
child: Text("display"))
],
),
),
); } }
and these are my models
class Model {
final name;
Model({this.name, this.list});
List<String>? list;
}
class ModelClass {
static List<Model> modelList = [];
}
my console outputs the following:
flutter: added text successfully
flutter: [a]
flutter: added text successfully
flutter: added text successfully
flutter: [a, aw, aw]
flutter: [a, aw, aw]
flutter: added text successfully
flutter: [a, aw, aw, wef]
flutter: [a, aw, aw, wef]
flutter: [a, aw, aw, wef]
flutter: [a, aw, aw, wef]
flutter: [a, aw, aw, wef]
flutter: [a, aw, aw, wef]
Related
im new to dart/flutter, im trying to make a textfield that user can input index value and a button to submit it. For example, if user input 1 and click submit , then it will print apple. Thank you for helping. The error i get is String can't be assigned to a int, can i know how to fix this. Thank you.
Here is my source code
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
appBar: AppBar(
title: const Text('Fruity App'),
),
body: MyWidget(),
),
);
}
}
class MyWidget extends StatefulWidget {
#override
_MyWidgetState createState() => _MyWidgetState();
}
class _MyWidgetState extends State<MyWidget> {
String _textString = 'Enter input to select your favourite fruit';
String _select =
'1 = Apple \n 2 = Pineapple \n 3 = Potato \n 4 = Orange \n 5 = Tomato';
var fruitsIndex = 0;
List<String> fruits = ['Apple', 'Pineapple', 'Potato', 'Orange', 'Tomato'];
TextEditingController a = new TextEditingController();
#override
Widget build(BuildContext context) {
return Column(
children: [
TextField(controller: a),
Text(
_textString,
style: TextStyle(fontSize: 25),
),
Text(
_select,
style: TextStyle(fontSize: 25),
),
RaisedButton(child: Text('Submit'), onPressed: buttonPressed),
],
);
}
void buttonPressed() {
print(fruits[a.text.toString()]);
}
}
Try parsing that user input to int.
fruits[int.parse(a.text)]
I want to create a list, those people location = "Barishal". That's why, I created a function and try to push data ( which data I obtained from getSpecific() function ) to a new list ( myList ). But It created a problem ....
here is my code-
class BookData extends ChangeNotifier {
List<MyModel> data = [
MyModel(name: "Abir", location: "Dhaka"),
MyModel(name: "Shuvro", location: "Barishal"),
MyModel(name: "Anik", location: "Barishal")
];
List<MyModel> get getMydata{
return data;
}
getSpecific (){
for(int i=0;i<data.length;i++){
if(data[i].location=="Barishal"){
print(data[i]);
return data[i];
}
}
}
List myList = getSpecific();
}
How can I fix this problem ?
You can copy paste run full code below
You can provide search string and use UnmodifiableListView<MyModel> and filter with _myData.where
code snippet
class BookData extends ChangeNotifier {
final List<MyModel> _myData = [
MyModel(name: "Abir", location: "Dhaka"),
MyModel(name: "Shuvro", location: "Barishal"),
MyModel(name: "Anik", location: "Barishal")
];
String _searchString = "";
UnmodifiableListView<MyModel> get books => _searchString.isEmpty
? UnmodifiableListView(_myData)
: UnmodifiableListView(
_myData.where((dog) => dog.location.contains(_searchString)));
void getSpecific(String searchString) {
_searchString = searchString;
print(_searchString);
notifyListeners();
}
}
working demo
full code
import 'package:flutter/material.dart';
import 'package:flutter/cupertino.dart';
import 'dart:collection';
import 'package:provider/provider.dart';
class BookData extends ChangeNotifier {
final List<MyModel> _myData = [
MyModel(name: "Abir", location: "Dhaka"),
MyModel(name: "Shuvro", location: "Barishal"),
MyModel(name: "Anik", location: "Barishal")
];
String _searchString = "";
UnmodifiableListView<MyModel> get books => _searchString.isEmpty
? UnmodifiableListView(_myData)
: UnmodifiableListView(
_myData.where((dog) => dog.location.contains(_searchString)));
void getSpecific(String searchString) {
_searchString = searchString;
print(_searchString);
notifyListeners();
}
}
class MyModel {
final String name;
final String location;
MyModel({this.name, this.location});
}
void main() {
runApp(
ChangeNotifierProvider(
create: (context) => BookData(),
child: MyApp(),
),
);
}
class MyApp extends StatefulWidget {
#override
_MyAppState createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
final _controller = TextEditingController();
String _searchText;
#override
void initState() {
_controller.addListener(
() {
setState(() {
_searchText = _controller.text;
});
},
);
super.initState();
}
#override
void dispose() {
_controller.dispose();
super.dispose();
}
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Example',
home: Scaffold(
appBar: AppBar(
title: Text('Example'),
),
body: Column(
mainAxisAlignment: MainAxisAlignment.start,
crossAxisAlignment: CrossAxisAlignment.center,
children: <Widget>[
TextField(
controller: _controller,
decoration: InputDecoration(
hintText: "Search",
prefixIcon: Icon(Icons.search),
border: OutlineInputBorder(
borderRadius: BorderRadius.all(
Radius.circular(4.0),
),
),
),
onChanged: (value) {
Provider.of<BookData>(context, listen: false)
.getSpecific(value);
},
),
Consumer<BookData>(builder: (context, bookData, child) {
print(bookData.books.toString());
return Expanded(
child: ListView.builder(
shrinkWrap: true,
itemCount: bookData.books.length,
itemBuilder: (context, index) => Card(
elevation: 3,
child: ListTile(
title: Text(bookData.books[index].name),
),
)),
);
}),
],
),
),
);
}
}
When you need to filter a list, you can use the where method.
Here's a simple example.
List<MyModel> myNewList = data.where((item) => item.location == "Barishal").toList();
Anyway, your code seems to be returning just the first item, not a list.
I fixed your code like below
List<MyModel> getSpecific (){
List<MyModel> result = [];
for(int i=0;i<data.length;i++){
if(data[i].location=="Barishal"){
print(data[i]);
result.add(data[i]);
}
}
return result;
}
I am trying to list categories of products in my app, and i am using provider package for state management. During the build time its shows the list is empty even though it is not, then I add a click event to update the list that time it works.
I call the getAllCategories() function during the splash screen and the vallCategoryList has values.
This is my category class
class Category with ChangeNotifier{
int catId;
String catName;
String catThumbnail;
List<SetCategory> allCategoryList = [];
void getAllCategories() async {
String categoryUrl = 'https://app.ecwid.com/api/ccccccc';
Response allCategory = await get(categoryUrl);
print('getAllCategories');
if (allCategory.statusCode == 200) {
var categoryData = allCategory.body;
int totalcount = jsonDecode(categoryData)['count'];
if (allCategoryList.length != totalcount) {
allCategoryList.clear();
for (int i = 0; i < totalcount; i++) {
allCategoryList.add(SetCategory(
catId: jsonDecode(categoryData)['items'][i]['id'],
catName: jsonDecode(categoryData)['items'][i]['name'],
catThumbnail: jsonDecode(categoryData)['items'][i]['thumbnailUrl'],
));
}
}
}
print('allcategorylist length ${allCategoryList.length}');
notifyListeners();
}
}
class SetCategory {
int catId;
String catName;
String catThumbnail;
SetCategory(
{ this.catId, this.catName, this.catThumbnail});
}
My code for screen
class HomeScreen extends StatefulWidget {
static const String id = 'homeScreen';
// static int reload = 0;
#override
_HomeScreenState createState() => _HomeScreenState();
}
class _HomeScreenState extends State<HomeScreen> {
#override
Widget build(BuildContext context) {
final category = Provider.of<Category>(context);
print('category length ${category.allCategoryList.length}'); // here it shows length as 0 even though it has a value of 16.
return Row(
children: <Widget>[
Padding(
padding: const EdgeInsets.all(8.0),
child: Text(
'Category ${category.allCategoryList.length}',
style: TextStyle(
color: Colors.black,
fontWeight: FontWeight.bold,
fontSize: 15.0,
),
textAlign: TextAlign.start,
),
),
InkWell(
onTap: () {
category.getAllCategories(); // when i tap here this updates the list
}),
],
),
Did you use ChangeNotifierProvider in your Widget as shown here
If you just used Provider it is not updating but just makes the object accessible from the descendants
Solved by adding a Consumer, changed code like this
child: Consumer<Category>(
builder: (_,category,__){
return ListView.builder();
}
I want to implement a searchbar in my flutter application. I have to go through a listview out of ListTiles. Here I want to check if the title of the listtile contains the letters in the search field. Is this possible with a List?
It does not have to be with the title. It could be something else with what I can identify the Tile. But please, not the index, the user would not know it.
Is a List the right widget or do I have to use something else to implement a search Engine in my Application
Rather than using a 3rd party package, you can use native showSearch() function :
showSearch(context: context, delegate: ListSearchDelegate());
And then a class extending SearchDelegate:
class ListSearchDelegate extends SearchDelegate{
ListSearchDelegate({Key key,}): super() ;
List<String> listItems = <String>['One', 'Two', 'Three', 'Four', 'Five'] ;
#override
List<Widget> buildActions(BuildContext context) {
return [
IconButton(
icon: Icon(Icons.clear),
onPressed: () {
query = '';
},
),
];
}
#override
Widget buildLeading(BuildContext context) {
return IconButton(
icon: Icon(Icons.arrow_back),
onPressed: () {
close(context, null);
},
);
}
#override
Widget buildResults(BuildContext context) {
List<String> subList ;
subList = query != '' ? listItems.where((item) => item.contains(query)).toList() :
listItems ;
return ListView.builder(
itemCount: subList.length,
itemBuilder: (context, index) {
return ListTile(
title: Text(subList[index]),
);
}
);
}
#override
Widget buildSuggestions(BuildContext context) {
return Container();
}
}
Try https://pub.dev/packages/flutter_search_panel
List<SearchItem<int>> data = [
SearchItem(0, 'This'),
SearchItem(1, 'is'),
SearchItem(2, 'a'),
SearchItem(3, 'test'),
SearchItem(4, '.'),
];
FlutterSearchPanel<int>(
padding: EdgeInsets.all(10.0),
selected: 3,
title: 'Demo Search Page',
data: data,
icon: new Icon(Icons.check_circle, color: Colors.white),
color: Colors.blue,
textStyle: new TextStyle(color: Colors.white, fontWeight: FontWeight.bold, fontSize: 20.0, decorationStyle: TextDecorationStyle.dotted),
onChanged: (int value) {
print(value);
},
),
I am using Flutter table calendar plugin to make a calendar. In order to put events into the calendar, I have to add data to _events map. I want to get the data from Firestore document, and put the data into _events map. However, I don't know how to do it. I search everywhere but I can't get an answer.
This is my code
class _MemberEventsState extends State<MemberEvents>
with TickerProviderStateMixin {
Map<DateTime, List> _events;
List _selectedEvents;
AnimationController _animationController;
CalendarController _calendarController;
List<String> list = List();
#override
void initState() {
super.initState();
final _selectedDay = DateTime.now();
Firestore.instance
.collection('events')
.document('2019-07-30')
.get()
.then((DocumentSnapshot ds) {
list = List.from(ds['title']);
});
_events = {DateTime.parse("2019-08-01"): list};
_selectedEvents = _events[_selectedDay] ?? [];
_calendarController = CalendarController();
_animationController = AnimationController(
vsync: this,
duration: const Duration(milliseconds: 400),
);
_animationController.forward();
}
#override
void dispose() {
_animationController.dispose();
_calendarController.dispose();
super.dispose();
}
void _onDaySelected(DateTime day, List events) {
print('CALLBACK: _onDaySelected');
setState(() {
_selectedEvents = events;
});
}
void _onVisibleDaysChanged(
DateTime first, DateTime last, CalendarFormat format) {
print('CALLBACK: _onVisibleDaysChanged');
}
#override
Widget build(BuildContext context) {
return new Scaffold(
body: Column(
mainAxisSize: MainAxisSize.max,
children: <Widget>[
_buildTableCalendar(),
const SizedBox(height: 8.0),
const SizedBox(height: 8.0),
Expanded(child: _buildEventList()),
],
),
);
}
Widget _buildTableCalendar() {
return TableCalendar(
calendarController: _calendarController,
events: _events,
startingDayOfWeek: StartingDayOfWeek.sunday,
calendarStyle: CalendarStyle(
selectedColor: Colors.deepOrange[400],
todayColor: Colors.blueAccent[200],
markersColor: Colors.brown[700],
outsideDaysVisible: false,
),
headerStyle: HeaderStyle(
formatButtonTextStyle:
TextStyle().copyWith(color: Colors.white, fontSize: 15.0),
formatButtonDecoration: BoxDecoration(
color: Colors.deepOrange[400],
borderRadius: BorderRadius.circular(16.0),
),
),
onDaySelected: _onDaySelected,
onVisibleDaysChanged: _onVisibleDaysChanged,
);
}
Widget _buildEventList() {
return ListView(
children: _selectedEvents
.map((event) => Container(
decoration: BoxDecoration(
border: Border.all(width: 0.8),
borderRadius: BorderRadius.circular(12.0),
),
margin:
const EdgeInsets.symmetric(horizontal: 8.0, vertical: 4.0),
child: ListTile(
title: Text(event.toString()),
),
))
.toList(),
);
}
}
So in the first step to achieve my goal, I made a document named 2019-07-30, then I made an array in it named title. Then I tried to get the values in the array to a List named list. However, list returned null.
I don't know where I went wrong.
I am new to Flutter, so the question might seem stupid.
Also, I am new to stackoverflow, so if I did any steps wrong on describing the question, please tell me so I can fix it.