Flutter 如何毫不延迟地在视频播放器上连续播放视频?
我希望在Flitter中重新创建Snapchat的背靠背视频格式。由于Flutter 如何毫不延迟地在视频播放器上连续播放视频?,flutter,dart,snapchat,instagram-story,flutter-video-player,Flutter,Dart,Snapchat,Instagram Story,Flutter Video Player,我希望在Flitter中重新创建Snapchat的背靠背视频格式。由于video\u player在视频结束时缺少回调(否则很容易回调地狱),我想知道是否有人对构建这样的东西有一些建议 import 'dart:async'; import 'package:flutter/material.dart'; import 'package:video_player/video_player.dart'; void main() { runApp(MaterialApp( title
video\u player
在视频结束时缺少回调(否则很容易回调地狱),我想知道是否有人对构建这样的东西有一些建议
import 'dart:async';
import 'package:flutter/material.dart';
import 'package:video_player/video_player.dart';
void main() {
runApp(MaterialApp(
title: 'My app', // used by the OS task switcher
home: MyHomePage(),
));
}
class MyHomePage extends StatefulWidget {
@override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
List<VideoPlayerController> _controllers = [];
VoidCallback listener;
bool _isPlaying = false;
int _current = 0;
@override
void initState() {
super.initState();
// Add some sample videos
_controllers.add(VideoPlayerController.network(
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4',
));
_controllers.add(VideoPlayerController.network(
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4',
));
_controllers.add(VideoPlayerController.network(
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4',
));
this.tick();
// Try refreshing by brute force (this isn't going too well)
new Timer.periodic(Duration(milliseconds: 100), (Timer t) {
int delta = 99999999;
if(_controllers[_current].value != null) {
delta = (_controllers[_current].value.duration.inMilliseconds - _controllers[_current].value.position.inMilliseconds);
}
print("Tick " + delta.toString());
if(delta < 500) {
_current += 1;
this.tick();
}
});
}
void tick() async {
print("Current: " + _current.toString());
await _controllers[_current].initialize();
await _controllers[_current].play();
print("Ready");
setState((){
_current = _current;
});
}
@override
Widget build(BuildContext context) {
return AspectRatio(
aspectRatio: _controllers[_current].value.aspectRatio,
// Use the VideoPlayer widget to display the video
child: VideoPlayer(_controllers[_current]),
);
}
}
导入'dart:async';
进口“包装:颤振/材料.省道”;
导入“package:video_player/video_player.dart”;
void main(){
runApp(材料应用程序)(
标题:“我的应用程序”,//由操作系统任务切换程序使用
主页:MyHomePage(),
));
}
类MyHomePage扩展StatefulWidget{
@凌驾
_MyHomePageState createState()=>\u MyHomePageState();
}
类_MyHomePageState扩展状态{
列表_控制器=[];
无效回调侦听器;
bool_isplay=false;
int _电流=0;
@凌驾
void initState(){
super.initState();
//添加一些示例视频
_控制器。添加(VideoPlayerController.network(
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4',
));
_控制器。添加(VideoPlayerController.network(
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4',
));
_控制器。添加(VideoPlayerController.network(
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4',
));
这个。勾选();
//尝试用蛮力刷新(这不太顺利)
新计时器。周期性(持续时间(毫秒:100),(计时器t){
内部增量=9999999;
if(_控制器[_当前].value!=null){
增量=(_控制器[_当前].value.duration.inmillizes-_控制器[_当前].value.position.inmillizes);
}
打印(“勾选”+delta.toString());
如果(δ<500){
_电流+=1;
这个。勾选();
}
});
}
void tick()异步{
打印(“当前:+_Current.toString());
等待_控制器[_当前]。初始化();
等待_控制器[_当前].play();
打印(“就绪”);
设置状态(){
_电流=_电流;
});
}
@凌驾
小部件构建(构建上下文){
返回AspectRatio(
aspectRatio:_控制器[_当前].value.aspectRatio,
//使用VideoPlayer小部件显示视频
子项:视频播放器(_控制器[_当前]),
);
}
}
我现在播放的是第一个视频,但是第一个和第二个视频之间有很长的延迟。我相信这与我无法摆脱连接到第0项的侦听器有关。初始化网络
VideoPlayerController
可能需要一些时间才能完成。您可以在播放当前视频时初始化下一个视频的控制器。这将占用更多的内存,但我认为如果只预缓冲一两个视频,不会产生太大的问题。然后,当按下下一个或上一个按钮时,视频就可以播放了
这是我的解决办法。它的功能,它预先缓冲上一个和下一个视频,完成后跳到下一个视频,显示当前位置和缓冲,暂停和长按播放
import 'package:flutter/material.dart';
import 'package:video_player/video_player.dart';
main() {
runApp(MaterialApp(
home: VideoPlayerDemo(),
));
}
class VideoPlayerDemo extends StatefulWidget {
@override
_VideoPlayerDemoState createState() => _VideoPlayerDemoState();
}
class _VideoPlayerDemoState extends State<VideoPlayerDemo> {
int index = 0;
double _position = 0;
double _buffer = 0;
bool _lock = true;
Map<String, VideoPlayerController> _controllers = {};
Map<int, VoidCallback> _listeners = {};
Set<String> _urls = {
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4#1',
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4#2',
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4#3',
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4#4',
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4#5',
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4#6',
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4#7',
};
@override
void initState() {
super.initState();
if (_urls.length > 0) {
_initController(0).then((_) {
_playController(0);
});
}
if (_urls.length > 1) {
_initController(1).whenComplete(() => _lock = false);
}
}
VoidCallback _listenerSpawner(index) {
return () {
int dur = _controller(index).value.duration.inMilliseconds;
int pos = _controller(index).value.position.inMilliseconds;
int buf = _controller(index).value.buffered.last.end.inMilliseconds;
setState(() {
if (dur <= pos) {
_position = 0;
return;
}
_position = pos / dur;
_buffer = buf / dur;
});
if (dur - pos < 1) {
if (index < _urls.length - 1) {
_nextVideo();
}
}
};
}
VideoPlayerController _controller(int index) {
return _controllers[_urls.elementAt(index)];
}
Future<void> _initController(int index) async {
var controller = VideoPlayerController.network(_urls.elementAt(index));
_controllers[_urls.elementAt(index)] = controller;
await controller.initialize();
}
void _removeController(int index) {
_controller(index).dispose();
_controllers.remove(_urls.elementAt(index));
_listeners.remove(index);
}
void _stopController(int index) {
_controller(index).removeListener(_listeners[index]);
_controller(index).pause();
_controller(index).seekTo(Duration(milliseconds: 0));
}
void _playController(int index) async {
if (!_listeners.keys.contains(index)) {
_listeners[index] = _listenerSpawner(index);
}
_controller(index).addListener(_listeners[index]);
await _controller(index).play();
setState(() {});
}
void _previousVideo() {
if (_lock || index == 0) {
return;
}
_lock = true;
_stopController(index);
if (index + 1 < _urls.length) {
_removeController(index + 1);
}
_playController(--index);
if (index == 0) {
_lock = false;
} else {
_initController(index - 1).whenComplete(() => _lock = false);
}
}
void _nextVideo() async {
if (_lock || index == _urls.length - 1) {
return;
}
_lock = true;
_stopController(index);
if (index - 1 >= 0) {
_removeController(index - 1);
}
_playController(++index);
if (index == _urls.length - 1) {
_lock = false;
} else {
_initController(index + 1).whenComplete(() => _lock = false);
}
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Playing ${index + 1} of ${_urls.length}"),
),
body: Stack(
children: <Widget>[
GestureDetector(
onLongPressStart: (_) => _controller(index).pause(),
onLongPressEnd: (_) => _controller(index).play(),
child: Center(
child: AspectRatio(
aspectRatio: _controller(index).value.aspectRatio,
child: Center(child: VideoPlayer(_controller(index))),
),
),
),
Positioned(
child: Container(
height: 10,
width: MediaQuery.of(context).size.width * _buffer,
color: Colors.grey,
),
),
Positioned(
child: Container(
height: 10,
width: MediaQuery.of(context).size.width * _position,
color: Colors.greenAccent,
),
),
],
),
floatingActionButton: Row(
mainAxisAlignment: MainAxisAlignment.end,
children: <Widget>[
FloatingActionButton(onPressed: _previousVideo, child: Icon(Icons.arrow_back)),
SizedBox(width: 24),
FloatingActionButton(onPressed: _nextVideo, child: Icon(Icons.arrow_forward)),
],
),
);
}
}
导入“包装:颤振/材料.省道”;
导入“package:video_player/video_player.dart”;
main(){
runApp(材料应用程序)(
主页:VideoPlayerDemo(),
));
}
类VideoPlayerDemo扩展StatefulWidget{
@凌驾
_VideoPlayerDemoState createState()=>\u VideoPlayerDemoState();
}
类\u VideoPlayerDemoState扩展了状态{
int指数=0;
双_位置=0;
双缓冲区=0;
布尔锁=真;
映射_控制器={};
映射_侦听器={};
设置_URL={
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4#1',
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4#2',
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4#3',
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4#4',
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4#5',
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4#6',
'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4#7',
};
@凌驾
void initState(){
super.initState();
如果(_url.length>0){
_初始化控制器(0)。然后((){
_播放控制器(0);
});
}
如果(_url.length>1){
_初始化控制器(1)。完成时(()=>_lock=false);
}
}
VoidCallback\u listenerSpawner(索引){
返回(){
int-dur=_控制器(索引).value.duration.in毫秒;
int pos=_控制器(索引).value.position.in毫秒;
int buf=_控制器(索引).value.buffered.last.end.inmillizes;
设置状态(){
如果(dur\u lock=false);
}
}
void\u nextVideo()异步{
if(_lock | | index==_url.length-1){
返回;
}
_lock=true;
_停止控制器(索引);
如果(索引-1>=0){
_移除控制器(索引-1);
}
_播放控制器(++索引);
如果(索引==\u url.length-1){
_锁=假;
}否则{
_初始化控制器(索引+1)。完成时(()=>_lock=false);
}
}
@凌驾
小部件构建(构建上下文){
返回脚手架(
appBar:appBar(
标题:文本(“播放${uURL.length}的${index+1}”),
),
主体:堆栈(
儿童:[
手势检测器(
仅长按开始:()=>_控制器(索引)。暂停(),
仅长按结束:()=>_控制器(索引).play(),
儿童:中心(
孩子:AspectRatio(
aspectRatio:_控制器(索引).value.aspectRatio,
子:中心(子:视频播放器(_控制器(索引)),
),
),
),
定位(
子:容器(
身高:10,
宽度:MediaQuery.of(context).size.width*\u缓冲区,
颜色:颜色。灰色,
),
),
定位(
子:容器(