Flutter - SwitchListTile - DRY code - dart

Question

Complete newbie, so bear with me. Just a question on how I could refactor my code using the DRY principle. I'm sure it can be done on such a simple example so here goes.... My code below shows three 'switchListTiles'. I've managed to work out how to create 3 switchListTiles on top of one another, and also how to get them to turn on/off individually. Its just that this means I'm creating the following function 3 times:
bool _value3 = false;
void _onChanged3(bool value3) {
setState(() {
_value3 = value3;
});
}
I'm sure there is a way I could change this so I don't have the same code three times.
Any help would be greatly appreciated
Many thanks in advance
import 'package:flutter/material.dart';
void main() {
runApp(new MaterialApp(
title: "Switch Widget Demo",
home: new MyApp(),
));
}
class MyApp extends StatefulWidget {
#override
_MyAppState createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
bool _value = false;
void _onChanged(bool value) {
setState(() {
_value = value;
});
}
bool _value2 = false;
void _onChanged2(bool value2) {
setState(() {
_value2 = value2;
});
}
bool _value3 = false;
void _onChanged3(bool value3) {
setState(() {
_value3 = value3;
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Switch Demo"),
backgroundColor: Colors.redAccent,
centerTitle: true,
),
body: Container(
padding: EdgeInsets.all(32.0),
child: Column(
children: <Widget>[
Switch(value: _value,
onChanged: (bool value) {_onChanged(value);}),
SwitchListTile(value: _value,
title: Text("Click Me"),
activeColor: Colors.red,
secondary: Icon(Icons.home),
subtitle: Text("For my small print"),
onChanged: (bool value) {_onChanged(value);}),
SwitchListTile(value: _value2,
title: Text("Click Me Again Please"),
activeColor: Colors.lightGreen,
secondary: Icon(Icons.perm_identity),
onChanged: (bool value2) {_onChanged2(value2);}),
SwitchListTile(value: _value3,
title: Text("And Again Please"),
activeColor: Colors.blueGrey,
subtitle: Text("Some more small print"),
secondary: Icon(Icons.person),
onChanged: (bool value) {_onChanged3(value);}),
],
),
),
);
}
}

Answer 1

You just need to refactor the SwitchListTiles into its separate class, then make List<SwitchListTiles> in the parent widget.
Here I create 20 of them with lesser code:
class MySwitchListTilesContainer extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
backgroundColor: Colors.grey[800],
body: ListView(
children: List.generate(20, (i)=>MySwitchListTile(
)),
),
);
}
}
class MySwitchListTile extends StatefulWidget {
#override
_MySwitchListTileState createState() => new _MySwitchListTileState();
}
class _MySwitchListTileState extends State<MySwitchListTile> {
bool _v = false;
#override
Widget build(BuildContext context) {
return SwitchListTile(
value:_v,
onChanged: (value)=>setState((){
_v=value;
}),
);
}
}