| Add Flutter example app with Linux runner 7fdf712 nandi 4h ago | 1 | import 'package:flutter/material.dart'; |
| 2 | import 'package:vflutter_ffi/vflutter_ffi.dart' as v; |
| 3 | |
| 4 | void main() => runApp(const ExampleApp()); |
| 5 | |
| 6 | class ExampleApp extends StatelessWidget { |
| 7 | const ExampleApp({super.key}); |
| 8 | |
| 9 | @override |
| 10 | Widget build(BuildContext context) => MaterialApp( |
| 11 | title: 'vflutter_ffi', |
| 12 | theme: ThemeData(colorSchemeSeed: Colors.indigo, useMaterial3: true), |
| 13 | home: const HomePage(), |
| 14 | ); |
| 15 | } |
| 16 | |
| 17 | class HomePage extends StatefulWidget { |
| 18 | const HomePage({super.key}); |
| 19 | |
| 20 | @override |
| 21 | State<HomePage> createState() => _HomePageState(); |
| 22 | } |
| 23 | |
| 24 | class _HomePageState extends State<HomePage> { |
| 25 | final _controller = TextEditingController(text: 'Flutter'); |
| 26 | |
| 27 | // Synchronous results are cheap enough to compute in build(); the async one |
| 28 | // is not, so it is held here and refreshed on demand. |
| 29 | String _async = '(not run)'; |
| 30 | String _stress = '(not run)'; |
| 31 | |
| 32 | @override |
| 33 | void dispose() { |
| 34 | _controller.dispose(); |
| 35 | super.dispose(); |
| 36 | } |
| 37 | |
| 38 | Future<void> _runAsync() async { |
| 39 | final r = await v.greetAsync(_controller.text); |
| 40 | setState(() => _async = r); |
| 41 | } |
| 42 | |
| 43 | /// 20k round trips on the UI isolate. Fast enough not to jank, and proves |
| 44 | /// the V side frees its temporaries under load. |
| 45 | void _runStress() { |
| 46 | final sw = Stopwatch()..start(); |
| 47 | for (var i = 0; i < 20000; i++) { |
| 48 | v.greet('stress$i'); |
| 49 | } |
| 50 | sw.stop(); |
| 51 | setState(() => _stress = '20k calls in ${sw.elapsedMilliseconds} ms'); |
| 52 | } |
| 53 | |
| 54 | @override |
| 55 | Widget build(BuildContext context) { |
| 56 | return Scaffold( |
| 57 | appBar: AppBar(title: const Text('V → Flutter over dart:ffi')), |
| 58 | body: Center( |
| 59 | child: ConstrainedBox( |
| 60 | constraints: const BoxConstraints(maxWidth: 520), |
| 61 | child: ListView( |
| 62 | padding: const EdgeInsets.all(24), |
| 63 | shrinkWrap: true, |
| 64 | children: [ |
| 65 | _Row(label: 'v.add(20, 22)', value: '${v.add(20, 42 - 20)}'), |
| 66 | const Divider(height: 32), |
| 67 | TextField( |
| 68 | controller: _controller, |
| 69 | decoration: const InputDecoration( |
| 70 | labelText: 'name', |
| 71 | border: OutlineInputBorder(), |
| 72 | ), |
| 73 | onChanged: (_) => setState(() {}), |
| 74 | ), |
| 75 | const SizedBox(height: 16), |
| 76 | _Row(label: 'v.greet(name)', value: v.greet(_controller.text)), |
| 77 | const Divider(height: 32), |
| 78 | _Row(label: 'v.greetAsync(name)', value: _async), |
| 79 | const SizedBox(height: 8), |
| 80 | FilledButton.tonal( |
| 81 | onPressed: _runAsync, |
| 82 | child: const Text('run on background isolate'), |
| 83 | ), |
| 84 | const Divider(height: 32), |
| 85 | _Row(label: 'ownership stress', value: _stress), |
| 86 | const SizedBox(height: 8), |
| 87 | FilledButton.tonal( |
| 88 | onPressed: _runStress, |
| 89 | child: const Text('run 20k round trips'), |
| 90 | ), |
| 91 | ], |
| 92 | ), |
| 93 | ), |
| 94 | ), |
| 95 | ); |
| 96 | } |
| 97 | } |
| 98 | |
| 99 | class _Row extends StatelessWidget { |
| 100 | const _Row({required this.label, required this.value}); |
| 101 | |
| 102 | final String label; |
| 103 | final String value; |
| 104 | |
| 105 | @override |
| 106 | Widget build(BuildContext context) { |
| 107 | final theme = Theme.of(context); |
| 108 | return Column( |
| 109 | crossAxisAlignment: CrossAxisAlignment.start, |
| 110 | children: [ |
| 111 | Text(label, style: theme.textTheme.labelMedium), |
| 112 | const SizedBox(height: 4), |
| 113 | SelectableText( |
| 114 | value, |
| 115 | style: theme.textTheme.titleMedium |
| 116 | ?.copyWith(fontFamily: 'monospace', color: theme.colorScheme.primary), |
| 117 | ), |
| 118 | ], |
| 119 | ); |
| 120 | } |
| 121 | } |