山西建设公司网站/怎样开网站

山西建设公司网站,怎样开网站,专业做国外网站,做调查问卷赚钱网站国外1. video_player 视频播放插件地址：https://pub.dev/packages/video_player 添加插件导入头文件 import package:video_player/video_player.dart;Android配置（iOS不用配置） 修改这个文件：/android/app/src/main/AndroidMani…

1. video_player 视频播放

插件地址：https://pub.dev/packages/video_player

添加插件
导入头文件

import 'package:video_player/video_player.dart';

Android配置（iOS不用配置）

修改这个文件：/android/app/src/main/AndroidManifest.xml;
添加下面的配置：

<uses-permission android:name="android.permission.INTERNET"/>

添加核心代码

初始化播放器：

Uri url = Uri.parse("https://flutter.github.io/assets-for-api-docs/assets/videos/bee.mp4");_videoPlayerController = VideoPlayerController.networkUrl(url);_videoPlayerController.initialize().then((_){print("播放器初始化完成");// 添加播放器的监听_videoPlayerController.addListener(_onVideoChange);// 设置自动播放_videoPlayerController.play();_isPlaying = true;setState(() {print("111111");});});

添加播放器的视图：

return VideoPlayer(_videoPlayerController);

退出页面时，需要销毁播放器：

 @overridevoid dispose() {_videoPlayerController.dispose();super.dispose();}

完整代码

import 'dart:async';import 'package:flutter/material.dart';
import 'package:video_player/video_player.dart';class VideoPlayerDemo extends StatefulWidget {const VideoPlayerDemo({super.key});@overrideState<VideoPlayerDemo> createState() => _VideoPlayerDemoState();
}class _VideoPlayerDemoState extends State<VideoPlayerDemo> {late VideoPlayerController _videoPlayerController;bool _isPlaying = false;double _progress = 0.0;// 添加播放状态的订阅，避免每次调用setState 重刷页面late StreamController _isPlayingController;// 添加播放进度的订阅，避免每次调用setState 重刷页面late StreamController _progressController;@overridevoid initState() {super.initState();_isPlayingController = StreamController.broadcast();_progressController = StreamController.broadcast();Uri url = Uri.parse("https://flutter.github.io/assets-for-api-docs/assets/videos/bee.mp4");_videoPlayerController = VideoPlayerController.networkUrl(url);_videoPlayerController.initialize().then((_){print("播放器初始化完成");// 添加播放器的监听_videoPlayerController.addListener(_onVideoChange);// 设置自动播放_videoPlayerController.play();_isPlaying = true;setState(() {});});}@overridevoid dispose() {_videoPlayerController.dispose();_isPlayingController.close();_progressController.close();super.dispose();}// 自定义播放器的监听回调的方法void _onVideoChange() {print("播放器的监听回调");if (_videoPlayerController.value.isInitialized) {final isPlaying = _videoPlayerController.value.isPlaying;if (isPlaying != _isPlaying) {_isPlaying = isPlaying;_isPlayingController.sink.add(_isPlaying);}// 更新播放进度final position = _videoPlayerController.value.position;final duration = _videoPlayerController.value.duration;if (duration != null) {_progress = position.inMilliseconds / duration.inMilliseconds;print("进度 = $_progress");_progressController.sink.add(_progress);}// 检查视频是否播放完毕if (position >= duration) {print('Video has completed playing.');_videoPlayerController.seekTo(Duration.zero); // 重置到开始位置_videoPlayerController.pause(); // 暂停播放_isPlaying = false;_isPlayingController.add(_isPlaying);}}}// 播放器的视图Widget _palyerViewWidget() {if (_videoPlayerController.value.isInitialized) {// 初始化成功return AspectRatio(aspectRatio: _videoPlayerController.value.aspectRatio,child: Stack(children: [// 播放器VideoPlayer(_videoPlayerController),// 添加进度条Align(alignment: Alignment.bottomCenter,child: _progressWidget(),)],));} else {// loading视图return CircularProgressIndicator();}}// 进度条Widget _progressWidget() {// 进度条变化比较频繁：用 StreamBuilder 减少内存的消耗return  StreamBuilder(stream: _progressController.stream, builder: (context, snapshot) {print("更新进度条");return SizedBox(height: 35,child: Slider(value: _progress,onChanged: (value) {print("onChanged");setState(() {_videoPlayerController.seekTo(Duration(milliseconds: (value * _videoPlayerController.value.duration.inMilliseconds).round()));});},),);});}@overrideWidget build(BuildContext context) {return Scaffold(appBar: AppBar(title: Text("Video_Player_demo"),),body: Center(child: _palyerViewWidget(),),floatingActionButton: FloatingActionButton(onPressed: (){if (_isPlaying) {// 正在播放_videoPlayerController.pause();_isPlaying = false;} else {_videoPlayerController.play();_isPlaying = true;}_isPlayingController.add(_isPlaying);},// 这个按钮变化比较频繁：用 StreamBuilder 减少内存的消耗child: StreamBuilder(stream: _isPlayingController.stream, builder: (context, snapshot) {return Icon(_isPlaying ? Icons.pause : Icons.play_arrow);}),),);}
}

效果图如下：

2. chewie 播放视频

在 Flutter 里官方提供了一个 video_player插件可以播放视频，但video_player有一些局限性:没法控制底部播放进度等。
所以可以用另外一个三方的视频播放库chewie。
chewie是一个非官方的第三方视频播放组件，看起来好像是基于 HTML5 播放的组件。
chewie 相对 video_player 来说，有控制栏和全屏的功能。
Chewie 使用 video_player 引擎并将其包裹在友好的 Material 或 Cupertino UI中！

插件地址：https://pub.dev/packages/chewie

引入插件
chewie基于video_player，所以要使用chewie必须配置video_player
导入头文件

import 'package:video_player/video_player.dart';
import 'package:chewie/chewie.dart';

Android配置（iOS不用配置）

修改这个文件：/android/app/src/main/AndroidManifest.xml;
添加下面的配置：

<uses-permission android:name="android.permission.INTERNET"/>

核心代码

import 'package:chewie/chewie.dart';
import 'package:video_player/video_player.dart';final videoPlayerController = VideoPlayerController.networkUrl(Uri.parse('https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4'));await videoPlayerController.initialize();final chewieController = ChewieController(videoPlayerController: videoPlayerController,autoPlay: true,looping: true,
);final playerWidget = Chewie(controller: chewieController,
);

退出页面时，需要销毁播放器：

 @overridevoid dispose() {_videoPlayerController.dispose();_chewieController.dispose();super.dispose();}

完整代码

import 'package:flutter/material.dart';
import 'package:video_player/video_player.dart';
import 'package:chewie/chewie.dart';class ChewieDemo extends StatefulWidget {const ChewieDemo({super.key});@overrideState<ChewieDemo> createState() => _ChewieDemoState();
}class _ChewieDemoState extends State<ChewieDemo> {late VideoPlayerController _videoPlayerController;late ChewieController _chewieController;@overridevoid initState() {super.initState();// 初始化播放器_initVideo();}@overridevoid dispose() {_videoPlayerController.dispose();_chewieController.dispose();super.dispose();}// 初始化播放器void _initVideo() async {Uri url = Uri.parse("https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4");_videoPlayerController = VideoPlayerController.networkUrl(url);await _videoPlayerController.initialize();_chewieController = ChewieController(videoPlayerController: _videoPlayerController,aspectRatio: _videoPlayerController.value.aspectRatio,autoPlay: true,looping: false);setState(() {});}@overrideWidget build(BuildContext context) {return Scaffold(appBar: AppBar(title: Text("Chewie demo-在线播放视频"),),body: Center(child: _videoPlayerController.value.isInitialized ? AspectRatio(aspectRatio: _videoPlayerController.value.aspectRatio,child: Chewie(controller: _chewieController),) : CircularProgressIndicator(),),);}
}