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import 'package:flutter/cupertino.dart';
import 'package:flutter/widgets.dart';
import 'app_bar.dart';
import 'button.dart';
import 'value_display.dart';
class PlaygroundPage extends StatefulWidget {
const PlaygroundPage({super.key});
@override
State<PlaygroundPage> createState() => _PlaygroundPageState();
}
class _PlaygroundPageState extends State<PlaygroundPage> {
int _counter = 0;
int _elapsedMilliseconds = 0;
final stopwatch = Stopwatch();
void increment() {
setState(() {
++_counter;
if (stopwatch.isRunning) {
stopwatch.stop();
_elapsedMilliseconds = stopwatch.elapsedMilliseconds;
stopwatch.reset();
}
else {
stopwatch.start();
_elapsedMilliseconds = 0;
}
});
}
void clear() {
setState(() {
if (stopwatch.isRunning) {
return;
}
_counter = 0;
_elapsedMilliseconds = 0;
});
}
@override
Widget build(BuildContext context) {
return Column(
children: [
const AppBar(),
Expanded(
child: Center(
child: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget> [
Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Button(onPressed: increment, buttonText: 'Increment'),
const SizedBox(height: 8),
Button(onPressed: clear, buttonText: 'Clear'),
],
),
const SizedBox(width: 16),
ValueDisplay(label: 'Count', value: _counter),
const SizedBox(width: 16),
ValueDisplay(label: 'Elapsed (ms)', value: _elapsedMilliseconds),
],
),
),
),
],
);
}
}
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