TextField TextController not working inside Stateful widget - flutter

Question

I have created a Stateful widget to show my Alert Dialog which contains a searchbar , however the search bar text doesn't update on typing and stays blank. I have set the controller of the textfield as TextEditingController() however its still not working.
code
import 'package:flutter/material.dart';
import 'package:flutter_convertor/Data Models/Society.dart';
class MyDialogContent extends StatefulWidget {
#override
_MyDialogContentState createState() => new _MyDialogContentState();
}
class _MyDialogContentState extends State<MyDialogContent> {
#override
void initState(){
super.initState();
}
#override
Widget build(BuildContext context) {
//Search bar
Container searchBar = Container(
child: Padding(
padding: const EdgeInsets.only(left: 0.0, right: 0.0),
child: TextField(
onChanged: (value) {
filterSearchResults(value);
},
controller: TextEditingController(),
decoration: InputDecoration(
labelText: "Search",
prefixIcon: Icon(Icons.search),
border: OutlineInputBorder(
borderRadius: BorderRadius.all(Radius.circular(15.0)))),
),
),
);
AlertDialog dialog = AlertDialog(
title: searchBar,
content: Container(
....
),
);
return dialog;
}
}
The controller works in my main dart file. but not when i put in my Alert Dialog stateful Widget

Answer 1

this one is the same way that you use, this will not work
import 'dart:async';
import 'package:flutter/material.dart';
import 'package:flutter/cupertino.dart';
class Sample extends StatefulWidget {
#override
_SampleState createState() => new _SampleState();
}
class _SampleState extends State<Sample> {
List<String> countries = <String>['Belgium','France','Italy','Germany','Spain','Portugal'];
int _selectedCountryIndex = 0;
#override
void initState() {
super.initState();
WidgetsBinding.instance.addPostFrameCallback((_){_showDialog();});
}
_buildList(){
if (countries.length == 0){
return new Container();
}
return new Column(
children: new List<RadioListTile<int>>.generate(
countries.length,
(int index){
return new RadioListTile<int>(
value: index,
groupValue: _selectedCountryIndex,
title: new Text(countries[index]),
onChanged: (int value) {
setState((){
_selectedCountryIndex = value;
});
},
);
}
)
);
}
_showDialog() async{
await showDialog<String>(
context: context,
builder: (BuildContext context){
return new CupertinoAlertDialog(
title: new Text('Please select'),
actions: <Widget>[
new CupertinoDialogAction(
isDestructiveAction: true,
onPressed: (){Navigator.of(context).pop('Cancel');},
child: new Text('Cancel'),
),
new CupertinoDialogAction(
isDestructiveAction: true,
onPressed: (){Navigator.of(context).pop('Accept');},
child: new Text('Accept'),
),
],
content: new SingleChildScrollView(
child: new Material(
child: _buildList(),
),
),
);
},
barrierDismissible: false,
);
}
#override
Widget build(BuildContext context) {
return new Container();
}
}
you should do it like below
import 'dart:async';
import 'package:flutter/material.dart';
import 'package:flutter/cupertino.dart';
class Sample extends StatefulWidget {
#override
_SampleState createState() => new _SampleState();
}
class _SampleState extends State<Sample> {
List<String> countries = <String>['Belgium','France','Italy','Germany','Spain','Portugal'];
#override
void initState() {
super.initState();
WidgetsBinding.instance.addPostFrameCallback((_){_showDialog();});
}
_showDialog() async{
await showDialog<String>(
context: context,
builder: (BuildContext context){
return new CupertinoAlertDialog(
title: new Text('Please select'),
actions: <Widget>[
new CupertinoDialogAction(
isDestructiveAction: true,
onPressed: (){Navigator.of(context).pop('Cancel');},
child: new Text('Cancel'),
),
new CupertinoDialogAction(
isDestructiveAction: true,
onPressed: (){Navigator.of(context).pop('Accept');},
child: new Text('Accept'),
),
],
content: new SingleChildScrollView(
child: new Material(
child: new MyDialogContent(countries: countries),
),
),
);
},
barrierDismissible: false,
);
}
#override
Widget build(BuildContext context) {
return new Container();
}
}
class MyDialogContent extends StatefulWidget {
MyDialogContent({
Key key,
this.countries,
}): super(key: key);
final List<String> countries;
#override
_MyDialogContentState createState() => new _MyDialogContentState();
}
class _MyDialogContentState extends State<MyDialogContent> {
int _selectedIndex = 0;
#override
void initState(){
super.initState();
}
_getContent(){
if (widget.countries.length == 0){
return new Container();
}
return new Column(
children: new List<RadioListTile<int>>.generate(
widget.countries.length,
(int index){
return new RadioListTile<int>(
value: index,
groupValue: _selectedIndex,
title: new Text(widget.countries[index]),
onChanged: (int value) {
setState((){
_selectedIndex = value;
});
},
);
}
)
);
}
#override
Widget build(BuildContext context) {
return _getContent();
}
}