Storage on every platform: the source

since 0.7.0 Widgets and the rest
Open the live demo · Read the guide · View on GitHub
Regions the guide quotes: text (line 38), remove (line 42), binary (line 45).
1/// Small documents a player's choices live in, kept the right way on
2/// whichever of five platforms is running: a file on four of them, an
3/// IndexedDB record for anything too big for `localStorage` on the fifth.
4///
5/// Quoted by `storage.md` and shown whole in the Source tab.
6library;

8import 'dart:typed_data';

10import 'package:flutter/widgets.dart';
11import 'package:flutter3d/flutter3d.dart';
12import 'package:flutter3d_app/flutter3d_app.dart';
13import 'package:flutter3d_showcase/src/demo/demo.dart';
14import 'package:vector_math/vector_math.dart';

16final class StorageDemo extends ShowcaseDemo {
late final String _report;

@override
Scene build(DemoContext context) {
  final material = Material(
    name: 'disk',
    baseColor: Vector4(0.6, 0.6, 0.7, 1.0),
  );
  final node = MeshNode(
    DeviceMesh.upload(context.device, SphereShape(segments: 16).build()),
    material,
  );
  return Scene()
    ..add(node)
    ..add(
      LightNode(name: 'sun', intensity: 3.0)
        ..setLocalForward(Vector3(-0.4, -1.0, -0.3)),
    );
}

static Future<String> _run() async {
  final storage = defaultStorage('flutter3d-showcase-demo');
  final wrote = storage.write('settings.json', '{"volume":0.8}');
  final readBack = storage.read('settings.json');

  storage.remove('settings.json');
  final afterRemove = storage.read('settings.json');

  final binary = defaultBinaryStorage('flutter3d-showcase-demo');
  final bytes = Uint8List.fromList(<int>[1, 2, 3, 4]);
  await binary.write('blob.bin', bytes);
  final readBytes = await binary.read('blob.bin');
  await binary.remove('blob.bin');

  return 'wrote: $wrote, read back: $readBack, after remove: $afterRemove\n'
      'binary round trip: $readBytes';
}

@override
Future<void> prepare(DemoContext context) async {
  _report = await _run();
}

@override
Widget? customBody(BuildContext buildContext, DemoContext context) =>
    Container(
      color: const Color(0xFF14161A),
      padding: const EdgeInsets.all(24),
      alignment: Alignment.topLeft,
      child: DefaultTextStyle(
        style: const TextStyle(color: Color(0xFFE8E8EC), fontSize: 16),
        child: Text(_report),
      ),
    );

@override
void verify(Scene scene, FrameResult frame) {
  if (frame.drawCalls < 1) {
    throw StateError('the disk marker was not drawn');
  }
  if (!_report.contains('read back: {"volume":0.8}')) {
    throw StateError('what was written should read back exactly');
  }
  if (!_report.contains('after remove: null')) {
    throw StateError('a removed document should read back as nothing');
  }
  if (!_report.contains('binary round trip: [1, 2, 3, 4]')) {
    throw StateError('the bytes written should read back exactly');
  }
}
87}