使用flutter写一个视频控制器

好的，以下是一个简单的Flutter视频控制器的实现：

import 'package:flutter/material.dart';
import 'package:video_player/video_player.dart';

class VideoPlayerController extends StatefulWidget {
  final String videoUrl;

  VideoPlayerController({required this.videoUrl});

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

class _VideoPlayerControllerState extends State<VideoPlayerController> {
  late VideoPlayerController _videoPlayerController;
  late Future<void> _initializeVideoPlayerFuture;

  @override
  void initState() {
    super.initState();

    // 创建一个VideoPlayerController对象
    _videoPlayerController = VideoPlayerController.network(widget.videoUrl);

    // 初始化VideoPlayerController对象
    _initializeVideoPlayerFuture = _videoPlayerController.initialize();

    // 开始播放视频
    _videoPlayerController.play();
  }

  @override
  void dispose() {
    // 释放VideoPlayerController对象
    _videoPlayerController.dispose();

    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: FutureBuilder(
        future: _initializeVideoPlayerFuture,
        builder: (context, snapshot) {
          if (snapshot.connectionState == ConnectionState.done) {
            return AspectRatio(
              aspectRatio: _videoPlayerController.value.aspectRatio,
              // 创建一个VideoPlayer对象
              child: VideoPlayer(_videoPlayerController),
            );
          } else {
            return Center(
              child: CircularProgressIndicator(),
            );
          }
        },
      ),
      bottomNavigationBar: BottomAppBar(
        child: Row(
          mainAxisAlignment: MainAxisAlignment.spaceBetween,
          children: [
            IconButton(
              icon: Icon(
                _videoPlayerController.value.isPlaying
                    ? Icons.pause
                    : Icons.play_arrow,
              ),
              onPressed: () {
                setState(() {
                  if (_videoPlayerController.value.isPlaying) {
                    _videoPlayerController.pause();
                  } else {
                    _videoPlayerController.play();
                  }
                });
              },
            ),
            IconButton(
              icon: Icon(Icons.fullscreen),
              onPressed: () {
                // 进入全屏模式
                _videoPlayerController.pause();
                Navigator.push(
                  context,
                  MaterialPageRoute(
                    builder: (context) => FullScreenVideoPlayer(
                      videoPlayerController: _videoPlayerController,
                    ),
                  ),
                );
              },
            ),
            IconButton(
              icon: Icon(Icons.volume_up),
              onPressed: () {
                setState(() {
                  _videoPlayerController.setVolume(1.0);
                });
              },
            ),
          ],
        ),
      ),
    );
  }
}

class FullScreenVideoPlayer extends StatefulWidget {
  final VideoPlayerController videoPlayerController;

  FullScreenVideoPlayer({required this.videoPlayerController});

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

class _FullScreenVideoPlayerState extends State<FullScreenVideoPlayer> {
  late VideoPlayerController _videoPlayerController;
  late Future<void> _initializeVideoPlayerFuture;

  @override
  void initState() {
    super.initState();

    // 初始化VideoPlayerController对象
    _videoPlayerController = widget.videoPlayerController;
    _initializeVideoPlayerFuture = _videoPlayerController.initialize();

    // 开始播放视频
    _videoPlayerController.play();
  }

  @override
  void dispose() {
    // 释放VideoPlayerController对象
    _videoPlayerController.dispose();

    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: FutureBuilder(
        future: _initializeVideoPlayerFuture,
        builder: (context, snapshot) {
          if (snapshot.connectionState == ConnectionState.done) {
            return AspectRatio(
              aspectRatio: _videoPlayerController.value.aspectRatio,
              // 创建一个VideoPlayer对象
              child: VideoPlayer(_videoPlayerController),
            );
          } else {
            return Center(
              child: CircularProgressIndicator(),
            );
          }
        },
      ),
      bottomNavigationBar: BottomAppBar(
        child: Row(
          mainAxisAlignment: MainAxisAlignment.spaceBetween,
          children: [
            IconButton(
              icon: Icon(
                _videoPlayerController.value.isPlaying
                    ? Icons.pause
                    : Icons.play_arrow,
              ),
              onPressed: () {
                setState(() {
                  if (_videoPlayerController.value.isPlaying) {
                    _videoPlayerController.pause();
                  } else {
                    _videoPlayerController.play();
                  }
                });
              },
            ),
            IconButton(
              icon: Icon(Icons.fullscreen_exit),
              onPressed: () {
                // 退出全屏模式
                _videoPlayerController.pause();
                Navigator.pop(context);
              },
            ),
            IconButton(
              icon: Icon(Icons.volume_up),
              onPressed: () {
                setState(() {
                  _videoPlayerController.setVolume(1.0);
                });
              },
            ),
          ],
        ),
      ),
    );
  }
}

以上代码创建了一个包含视频播放器的页面，并在底部添加了一些控制按钮。在底部导航栏中，有一个“全屏”按钮，可以让用户进入全屏模式观看视频。同时，该页面也为竖屏模式做了适配，保证用户在不同设备上都能获得良好的观看体验。