flutter/dev/benchmarks/platform_views_layout/lib/main.dart

// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import 'dart:io';

import 'package:flutter/material.dart';
import 'package:flutter/scheduler.dart' show timeDilation;

void main() {
  runApp(
    const PlatformViewApp()
  );
}

class PlatformViewApp extends StatefulWidget {
  const PlatformViewApp({
    Key key
  }) : super(key: key);

  @override
  PlatformViewAppState createState() => PlatformViewAppState();

  static PlatformViewAppState of(BuildContext context) => context.findAncestorStateOfType<PlatformViewAppState>();
}

class PlatformViewAppState extends State<PlatformViewApp> {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData.light(),
      title: 'Advanced Layout',
      home: const PlatformViewLayout(),
    );
  }

  void toggleAnimationSpeed() {
    setState(() {
      timeDilation = (timeDilation != 1.0) ? 1.0 : 5.0;
    });
  }
}

class PlatformViewLayout extends StatelessWidget {
  const PlatformViewLayout({ Key key }) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('Platform View Scrolling Layout')),
      body: ListView.builder(
        key: const Key('platform-views-scroll'), // This key is used by the driver test.
        itemCount: 200,
        itemBuilder: (BuildContext context, int index) {
          return Padding(
            padding: const EdgeInsets.all(5.0),
            child: Material(
              elevation: (index % 5 + 1).toDouble(),
              color: Colors.white,
              child: Stack(
                children: const <Widget> [
                  DummyPlatformView(),
                  RotationContainer(),
                ],
              ),
            ),
          );
        },
      ),
    );
  }
}

class DummyPlatformView extends StatelessWidget {
  const DummyPlatformView({Key key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    const String viewType = 'benchmarks/platform_views_layout/DummyPlatformView';
    Widget nativeView;
    if (Platform.isIOS) {
      nativeView = const UiKitView(
        viewType: viewType,
      );
    } else if (Platform.isAndroid) {
      nativeView = const AndroidView(
        viewType: viewType,
      );
    } else {
      assert(false, 'Invalid platform');
    }
    return Container(
      color: Colors.purple,
      height: 200.0,
      child: nativeView,
    );
  }
}

class RotationContainer extends StatefulWidget {
  const RotationContainer({Key key}) : super(key: key);

  @override
  _RotationContainerState createState() => _RotationContainerState();
}

class _RotationContainerState extends State<RotationContainer>
  with SingleTickerProviderStateMixin {
  AnimationController _rotationController;

  @override
  void initState() {
    super.initState();
    _rotationController = AnimationController(
      vsync: this,
      duration: const Duration(seconds: 1),
      value: 1,
    );
    _rotationController.repeat();
  }
  @override
  Widget build(BuildContext context) {
    return RotationTransition(
      turns: Tween<double>(begin: 0.0, end: 1.0).animate(_rotationController),
      child: Container(
        color: Colors.purple,
        width: 50.0,
        height: 50.0,
      ),
    );
  }
}