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@burhanrashid52
Last active April 26, 2023 09:45
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import 'package:flutter/material.dart';
const Color darkBlue = Color.fromARGB(255, 18, 32, 47);
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
theme: ThemeData.dark().copyWith(
scaffoldBackgroundColor: darkBlue,
),
debugShowCheckedModeBanner: false,
home: const Scaffold(
body: Center(
child: MyWidget(),
),
),
);
}
}
class MyWidget extends StatefulWidget {
const MyWidget({Key? key}) : super(key: key);
@override
State<MyWidget> createState() => _MyWidgetState();
}
class _MyWidgetState extends State<MyWidget> {
double lerp = 0;
Color buttonColor = Colors.blue[100]!;
@override
Widget build(BuildContext context) {
return Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: <Widget>[
StatefulBuilder(
builder: (context, setBuilderState) {
return InexpensiveWidget(
color: Color.lerp(buttonColor, Colors.black, lerp)!,
onPressed: () {
setBuilderState(() {
lerp += 0.1;
if (lerp > 1) {
lerp = 0;
}
});
if (lerp == 0.5) {
setState(() {});
}
},
);
},
),
// Pretend `const` is not feasible here
// ignore: prefer_const_constructors
ExpensiveWidget(),
MaterialButton(
child: const Text("Open Dialog"),
onPressed: () => showAlertDialog(context),
)
],
),
);
}
}
class InexpensiveWidget extends StatelessWidget {
const InexpensiveWidget({
Key? key,
required this.color,
required this.onPressed,
}) : super(key: key);
final VoidCallback onPressed;
final Color color;
@override
Widget build(BuildContext context) {
print(" building InexpensiveWidget");
return TextButton(
onPressed: onPressed,
style: ButtonStyle(backgroundColor: MaterialStateProperty.all(color)),
child: const Text("I rebuild often"),
);
}
}
Future<void> showAlertDialog(BuildContext context) {
return showDialog<void>(
context: context,
builder: (BuildContext context) {
int count = 0;
return AlertDialog(
content: Column(
children: [
StatefulBuilder(
builder: (BuildContext context, StateSetter setState) {
return MaterialButton(
child: Text('Inside Increment $count'),
onPressed: () {
setState(() {
count++;
});
},
);
},
),
MaterialButton(
child: Text('Outside Increment $count'),
onPressed: () {
count++;
},
)
],
),
);
},
);
}
class ExpensiveWidget extends StatelessWidget {
const ExpensiveWidget({Key? key}) : super(key: key);
@override
Widget build(BuildContext context) {
print('Painstakingly building ExpensiveWidget');
return const Text("I'm expensive!");
}
}
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