网站开发客户哪里找,wordpress首页显示vip标志,线下推广方式有哪些,wordpress手机版侧栏导航flutter开发实战-实现获取视频的缩略图封面video_thumbnail
在很多时候#xff0c;我们查看视频的时候#xff0c;视频没有播放时候#xff0c;会显示一张封面#xff0c;可能封面没有配置图片#xff0c;这时候就需要通过获取视频的缩略图来显示封面了。这里使用了video…flutter开发实战-实现获取视频的缩略图封面video_thumbnail
在很多时候我们查看视频的时候视频没有播放时候会显示一张封面可能封面没有配置图片这时候就需要通过获取视频的缩略图来显示封面了。这里使用了video_thumbnail来实现获取视频的缩略图。
一、引入video_thumbnail
在工程的pubspec.yaml中引入插件 # 视频缩略图video_thumbnail: ^0.5.3
VideoThumbnail的属性如下
static FutureString? thumbnailFile({required String video,MapString, String? headers,String? thumbnailPath,ImageFormat imageFormat ImageFormat.PNG,int maxHeight 0,int maxWidth 0,int timeMs 0,int quality 10})
thumbnailPath为本地存储的文件目录imageFormat格式 jpgpng等video视频地址timeMs
二、获取视频的缩略图
使用video_thumbnail来获取视频缩略图
定义视频缩略图信息
class VideoThumbInfo {String url; // 原视频地址File? thumbFile; // 缩略图本地fileint? width; // 缩略图的widthint? height; // 缩略图的heightVideoThumbInfo({required this.url,});
}
获取视频缩略图本地File
String path (await getTemporaryDirectory()).path;String thumbnailPath path /${DateTime.now().millisecond}.jpg;final fileName await VideoThumbnail.thumbnailFile(video:https://vd2.bdstatic.com/mda-maif0tt1rirqp27q/540p/h264_cae/1611052585/mda-maif0tt1rirqp27q.mp4,thumbnailPath: thumbnailPath,imageFormat: imageFormat,quality: quality,maxWidth: maxWidth,maxHeight: maxHeight,timeMs: timeMs,);File file File(thumbnailPath);
获取缩略图的宽高
Image image Image.file(thumbFile!);image.image.resolve(const ImageConfiguration()).addListener(ImageStreamListener((ImageInfo imageInfo, bool synchronousCall) {int imageWidth imageInfo.image.width;int imageHeight imageInfo.image.height;VideoThumbInfo videoThumbInfo VideoThumbInfo(url: url);videoThumbInfo.thumbFile thumbFile;videoThumbInfo.width imageWidth;videoThumbInfo.height imageHeight;VideoThumb.setThumbInfo(url, videoThumbInfo);onVideoThumbInfoListener(videoThumbInfo);},onError: (exception, stackTrace) {print(getVideoThumbInfoByFile imageStreamListener onError exception:${exception.toString()},stackTrace:${stackTrace});onVideoThumbInfoListener(null);},),);
完整代码如下
import dart:io;
import package:flutter/material.dart;
import package:path_provider/path_provider.dart;
import package:video_thumbnail/video_thumbnail.dart;// ignore: non_constant_identifier_names
VideoThumbManager get VideoThumb VideoThumbManager.instance;class VideoThumbManager {static VideoThumbManager get instance {return _singleton;}//保存单例static VideoThumbManager _singleton VideoThumbManager._internal();//工厂构造函数factory VideoThumbManager() _singleton;//私有构造函数VideoThumbManager._internal();// 保存url对应的本地缩略图filefinal _thumbMap MapString, File();// url对应本地缩略图的信息final _thumbInfoMap MapString, VideoThumbInfo();Futurevoid setThumb(String url, File file) async {if (url.isEmpty) {return;}bool exist await file.exists();if (exist false) {return;}_thumbMap[url] file;}FutureFile? getThumb(String url, {ImageFormat imageFormat ImageFormat.JPEG,int maxHeight 0,int maxWidth 0,int timeMs 0,int quality 100,}) async {File? thumbFile _thumbMap[url];if (thumbFile ! null) {return thumbFile;}String path (await getTemporaryDirectory()).path;String thumbnailPath path /${DateTime.now().millisecond}.jpg;final fileName await VideoThumbnail.thumbnailFile(video:https://vd2.bdstatic.com/mda-maif0tt1rirqp27q/540p/h264_cae/1611052585/mda-maif0tt1rirqp27q.mp4,thumbnailPath: thumbnailPath,imageFormat: imageFormat,quality: quality,maxWidth: maxWidth,maxHeight: maxHeight,timeMs: timeMs,);File file File(thumbnailPath);setThumb(url, file);return file;}// 获取缩略图的大小void getVideoThumbInfo(String url, {ImageFormat imageFormat ImageFormat.JPEG,int maxHeight 0,int maxWidth 0,int timeMs 0,int quality 100,required Function(VideoThumbInfo?) onVideoThumbInfoListener,}) async {try {VideoThumbInfo? thumbInfo VideoThumb.getThumbInfo(url);if (thumbInfo ! null) {onVideoThumbInfoListener(thumbInfo);return;}await VideoThumb.getThumb(url,imageFormat: imageFormat,maxWidth: maxWidth,maxHeight: maxHeight,timeMs: timeMs,quality: quality,).then((value) {File? thumbFile value;if (thumbFile ! null) {VideoThumb.getVideoThumbInfoByFile(url: url,thumbFile: thumbFile,onVideoThumbInfoListener: onVideoThumbInfoListener,);} else {onVideoThumbInfoListener(null);}}).onError((error, stackTrace) {print(getVideoThumbInfo error:${error.toString()});onVideoThumbInfoListener(null);}).whenComplete(() {print(getVideoThumbInfo whenComplete);});} catch (e) {print(getVideoThumbInfo catch error:${e.toString()});onVideoThumbInfoListener(null);}}/// 根据file获取缩略图信息void getVideoThumbInfoByFile({required String url,required File thumbFile,required Function(VideoThumbInfo?) onVideoThumbInfoListener,}) async {try {VideoThumbInfo? thumbInfo VideoThumb.getThumbInfo(url);if (thumbInfo ! null) {onVideoThumbInfoListener(thumbInfo);return;}Image image Image.file(thumbFile!);image.image.resolve(const ImageConfiguration()).addListener(ImageStreamListener((ImageInfo imageInfo, bool synchronousCall) {int imageWidth imageInfo.image.width;int imageHeight imageInfo.image.height;VideoThumbInfo videoThumbInfo VideoThumbInfo(url: url);videoThumbInfo.thumbFile thumbFile;videoThumbInfo.width imageWidth;videoThumbInfo.height imageHeight;VideoThumb.setThumbInfo(url, videoThumbInfo);onVideoThumbInfoListener(videoThumbInfo);},onError: (exception, stackTrace) {print(getVideoThumbInfoByFile imageStreamListener onError exception:${exception.toString()},stackTrace:${stackTrace});onVideoThumbInfoListener(null);},),);} catch (e) {print(getVideoThumbInfoByFile catch error:${e.toString()});onVideoThumbInfoListener(null);}}void removeThumb(String url) {if (url.isEmpty) {return;}_thumbMap.remove(url);}/// 获取存储缩略图信息VideoThumbInfo? getThumbInfo(String url) {if (url.isEmpty) {return null;}VideoThumbInfo? thumbInfo _thumbInfoMap[url];return thumbInfo;}/// 存储缩略图信息void setThumbInfo(String url, VideoThumbInfo videoThumbInfo) async {if (url.isEmpty) {return;}_thumbInfoMap[url] videoThumbInfo;}void removeThumbInfo(String url) {if (url.isEmpty) {return;}_thumbInfoMap.remove(url);}void clear() {_thumbMap.clear();_thumbInfoMap.clear();}
}class VideoThumbInfo {String url; // 原视频地址File? thumbFile; // 缩略图本地fileint? width; // 缩略图的widthint? height; // 缩略图的heightVideoThumbInfo({required this.url,});
}
三、显示视频缩略图的Widget
用于显示视频缩略图的Widget
/// 用于显示视频缩略图的Widget
class VideoThumbImage extends StatefulWidget {const VideoThumbImage({super.key, required this.url, this.maxWidth, this.maxHeight});final String url;final double? maxWidth;final double? maxHeight;overrideStateVideoThumbImage createState() _VideoThumbImageState();
}class _VideoThumbImageState extends StateVideoThumbImage {VideoThumbInfo? _videoThumbInfo;overridevoid initState() {// TODO: implement initStatesuper.initState();VideoThumb.getVideoThumbInfo(widget.url,onVideoThumbInfoListener: (VideoThumbInfo? thumbInfo) {if (mounted) {setState(() {_videoThumbInfo thumbInfo;});}});}overridevoid dispose() {// TODO: implement disposesuper.dispose();}// 根据VideoThumb来显示图片Widget buildVideoThumb(BuildContext context) {if (_videoThumbInfo ! null _videoThumbInfo!.thumbFile ! null) {double? imageWidth;double? imageHeight;if (_videoThumbInfo!.width ! null _videoThumbInfo!.height ! null) {imageWidth _videoThumbInfo!.width!.toDouble();imageWidth _videoThumbInfo!.height!.toDouble();}return Container(width: imageWidth,height: imageHeight,clipBehavior: Clip.hardEdge,decoration: const BoxDecoration(color: Colors.transparent,),child: Image.file(_videoThumbInfo!.thumbFile!,width: imageWidth,height: imageHeight,),);}return Container();}overrideWidget build(BuildContext context) {return ConstrainedBox(constraints: BoxConstraints(maxWidth: widget.maxWidth ?? double.infinity,maxHeight: widget.maxHeight ?? double.infinity,),child: buildVideoThumb(context),);}
}
效果图如下 四、小结
flutter开发实战-实现获取视频的缩略图封面video_thumbnail
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