constbench.dart

import 'package:flutter/material.dart';

void main() {
  runApp(
    new MaterialApp(
      title: "Flutter Demo",
      routes: <String, RouteBuilder>{
        '/': (RouteArguments args) {
          return new Scaffold(
            toolBar: new ToolBar(
              center: new Text('Benchmark')
            ),
            body: new MaterialList(
              type: MaterialListType.oneLineWithAvatar,
              children: <Widget>[
                new ListItem(
                  onTap: () {
                    Navigator.pushNamed(args.context, '/const');
                  },
                  left: new CircleAvatar(
                    label: 'C'
                  ),
                  center: new Text('Using "const"')
                ),
                new ListItem(
                  onTap: () {
                    Navigator.pushNamed(args.context, '/new');
                  },
                  left: new CircleAvatar(
                    label: 'N'
                  ),
                  center: new Text('Using "new"')
                )
              ]
            )
          );
        },
        '/const': (RouteArguments args) {
          return new Scaffold(
            toolBar: new ToolBar(
              center: new Text('Using "const"')
            ),
            body: const ConstBenchmark()
          );
        },
        '/new': (RouteArguments args) {
          return new Scaffold(
            toolBar: new ToolBar(
              center: new Text('Using "new"')
            ),
            body: new NewBenchmark()
          );
        }
      }
    )
  );
}

class ConstBenchmark extends StatefulComponent {
  const ConstBenchmark();
  State createState() => new ConstBenchmarkState();
}

class NewBenchmark extends StatefulComponent {
  NewBenchmark();
  State createState() => new NewBenchmarkState();
}

abstract class BenchmarkState extends State {
  Widget build(BuildContext context) {
    List<Widget> children = <Widget>[];
    Stopwatch sw = new Stopwatch();
    sw.start();
    fillList(children);
    sw.stop();
    print('$this : ${sw.elapsedMicroseconds}µs');
    return new ScrollableGrid(
      children: children,
      delegate: new MaxTileWidthGridDelegate(
        maxTileWidth: 80.0
      )
    );
  }
  void fillList(List<Widget> list);
}

class ConstBenchmarkState extends BenchmarkState {
  void fillList(List<Widget> list) {
    for (int index = 0; index < 1000; index += 1) {
      list.add(new Container(
        decoration: const BoxDecoration(
          backgroundColor: const Color(0xFFFF7F00),
          borderRadius: 2.0
        ),
        padding: const EdgeDims.all(1.0),
        margin: const EdgeDims.all(1.0),
        constraints: const BoxConstraints.expand()
      ));
    }
  }
}

class NewBenchmarkState extends BenchmarkState {
  void fillList(List<Widget> list) {
    for (int index = 0; index < 1000; index += 1) {
      list.add(new Container(
        decoration: new BoxDecoration(
          backgroundColor: new Color(0xFFFF7F00),
          borderRadius: 2.0
        ),
        padding: new EdgeDims.all(1.0),
        margin: new EdgeDims.all(1.0),
        constraints: new BoxConstraints.loose(new Size(2.0, 2.0))
      ));
    }
  }
}