我不得不尝试多种视频下载功能，并且运行良好，但是我必须使用ListTile和右侧下载图标来实现listview。如果用户单击了下载图标，则隐藏下载图标并显示小进度以开始下载。但是它不起作用，进度条也没有显示，我的意思是当时用户界面没有刷新。
预先感谢
这是我的主屏幕
import 'dart:async';
import 'dart:io';
import 'package:dowload_sample/Golbals.dart';
import 'package:dowload_sample/VideoModel.dart';
import 'package:dowload_sample/database_helper.dart';
import 'package:dowload_sample/test.dart';
import 'package:flutter/material.dart';
import 'package:flutter/widgets.dart';
import 'package:flutter_downloader/flutter_downloader.dart';
import 'package:path/path.dart';
import 'package:path_provider/path_provider.dart';
import 'package:scoped_model/scoped_model.dart';
class HomePageNew extends StatefulWidget {
@override
_HomePage createState() => _HomePage();
}
class _HomePage extends State<HomePageNew> {
VideoModel myModel = new VideoModel();
VideoDownloader downloader;
@override
void initState() {
// TODO: implement initState
myModel.fetchVideoListFromDatabase();
super.initState();
this.downloader = new VideoDownloader();
}
@override
Widget build(BuildContext context) {
this.downloader = new VideoDownloader();
return new Scaffold(
backgroundColor: Colors.grey,
appBar: new AppBar(
title: new Text(
'Multiple Downloader Demo',
style: new TextStyle(color: Colors.white),
),
actions: <Widget>[
new IconButton(
icon: new Icon(
Icons.add,
color: Colors.black,
),
),
],
backgroundColor: Colors.green,
),
body: ScopedModel<VideoModel>(
model: myModel,
child: _buildListView(),
),
);
}
_buildListView() {
return ScopedModelDescendant<VideoModel>(
builder: (BuildContext context, Widget child, VideoModel model) {
final userList = model.users;
return ListView.builder(
itemBuilder: (context, index) => InkWell(
splashColor: Colors.blue[300],
child: _buildListTile(userList[index], index),
onTap: () {
print("Video Name: ${userList[index].videoName}");
},
),
itemCount: userList.length,
);
},
);
}
_buildListTile(VideoModel userModel, int index) {
return Card(
child: ListTile(
leading: Icon(Icons.video_label),
title: Text(userModel.videoName),
trailing: new ScopedModelDescendant<VideoModel>(builder:
(BuildContext context, Widget child, VideoModel videosModel) {
final isList = videosModel.users;
if (isList[index].state == VideoeState.downloading) {
print("Progress Icon");
return new Container(
height: 32.0,
width: 32.0,
child: new Padding(
padding: EdgeInsets.all(6.0),
child: new CircularProgressIndicator(
strokeWidth: 2.0, value: videosModel.downloadProgress),
));
} else if (isList[index].state == VideoeState.toDownload) {
if (isList[index].videoLocalURL == "" &&
isList[index].videoLocalURL.length == 0) {
print("Download Icon");
return new Container(
height: 32.0,
width: 32.0,
child: new IconButton(
icon: new Icon(Icons.cloud_download),
onPressed: () {
setState(() {
Globals.videoID = isList[index].videoID.toString();
downloader.performDownloadVideo(
isList[index].videoLiveURL,
isList[index].videoName,
isList[index]);
});
}));
} else {
print("Play Icon");
return new IconButton(
icon: new Icon(Icons.play_arrow),
onPressed: () {
print(
"Going to play Video ${isList[index].videoName} from ${isList[index].videoLocalURL}");
});
}
} else {
print("Play Default Icon");
return new IconButton(
icon: new Icon(Icons.play_arrow),
onPressed: () {
// Ellipsis
print(
"Going to play Video ${videosModel.videoName} from ${videosModel.videoLocalURL}");
});
}
}),
),
);
}
}
class DownloadInfo {
VideoModel model;
String taskId;
String filePath;
DownloadInfo({this.model, this.taskId, this.filePath});
}
class VideoDownloader {
List<DownloadInfo> _downloadInfoList;
VideoDownloader() {
this._downloadInfoList = new List();
FlutterDownloader.registerCallback((id, status, progress) {
DownloadInfo downloadInfo = this.getDownloadInfoFromTaskId(id);
if (downloadInfo != null) {
if (status == DownloadTaskStatus.running) {
downloadInfo.model.setState(VideoeState.downloading);
downloadInfo.model.setDownloadProgress(progress / 100.0);
} else if (status == DownloadTaskStatus.complete) {
downloadInfo.model.setState(VideoeState.downloaded);
downloadInfo.model.setDownloadProgress(1.0);
} else {
downloadInfo.model.setState(VideoeState.toDownload);
downloadInfo.model.setDownloadProgress(0.0);
}
}
print(
'Download task ($id) is in status ($status) and process ($progress)');
if (progress == 100) {
DatabaseHelper.updateLocalVideoPath(
"${Globals.filePath}${"/" + Globals.fileName}", Globals.videoID);
}
});
}
Future<void> performDownloadVideo(
String liveURL, String videoName, VideoModel video) async {
var link = liveURL;
var path = await getVideosDirectoryPath();
var filename = videoName + ".mp4";
print("Downloading $link as $filename in $path");
Globals.filePath = path;
Globals.fileName = filename;
String taskId = await FlutterDownloader.enqueue(
url: link,
savedDir: path,
fileName: filename,
showNotification: true,
);
return _downloadInfoList.add(new DownloadInfo(
taskId: taskId,
model: video,
filePath: join(path, filename),
));
}
Future<void> onComplete(DownloadInfo downloadInfo) async {
downloadInfo.model.setLocalFilePath(downloadInfo.filePath);
}
DownloadInfo getDownloadInfoFromTaskId(String taskId) {
if (this._downloadInfoList.length < 1) return null;
return this
._downloadInfoList
.firstWhere((dli) => dli.taskId == taskId, orElse: () => null);
}
static Future<String> getVideosDirectoryPath() async {
final directory = await getApplicationDocumentsDirectory();
final String videosPath = join(directory.path, "videos");
// Creating directory
await new Directory(videosPath).create(recursive: true);
return videosPath;
}
}
This is Model Class
import 'dart:convert';
import 'package:dowload_sample/HomePage.dart';
import 'package:dowload_sample/database_helper.dart';
import 'package:flutter/material.dart';
import 'package:scoped_model/scoped_model.dart';
enum VideoeState { toDownload, downloading, downloaded, playing, paused }
class VideoModel extends Model {
String videoID = null;
String videoName = null;
String videoLiveURL = null;
String videoLocalURL;
VideoeState state;
double downloadProgress;
String localFilePath;
VideoeState get state1 => this.state ?? VideoeState.toDownload;
VideoModel(
{this.videoID,
@required this.videoName,
@required this.videoLiveURL,
@required this.videoLocalURL});
VideoModel.map(dynamic obj) {
this.videoID = obj["videoID"];
this.videoName = obj["videoName"];
this.videoLiveURL = obj["videoLiveURL"];
this.videoLocalURL = obj["videoLocalURL"];
this.state = VideoeState.toDownload;
this.downloadProgress = 0.0;
}
void setState(VideoeState state) {
this.state = state;
notifyListeners();
}
List<VideoModel> _userList = [];
List<VideoModel> get users => _userList;
set _users(List<VideoModel> value) {
_userList = value;
notifyListeners();
}
double get downloadProgress1 => this.downloadProgress ?? 0.0;
void setDownloadProgress(double x) {
this.downloadProgress = x;
notifyListeners();
}
String get localFilePath1 => this.localFilePath;
void setLocalFilePath(String filePath) {
if (filePath == null) {
return;
}
this.localFilePath = filePath;
if (this.state == VideoeState.downloading ||
this.state == VideoeState.toDownload) {
this.state = VideoeState.downloaded;
}
notifyListeners();
}
Map<String, dynamic> toMap() {
var map = new Map<String, dynamic>();
map["videoID"] = videoID;
map["videoName"] = videoName;
map["videoLiveURL"] = videoLiveURL;
map["videoLocalURL"] = videoLocalURL;
return map;
}
//Fetch data from the local data base
Future<List<VideoModel>> fetchVideoListFromDatabase() async {
DatabaseHelper dbHelper = DatabaseHelper();
_users = await dbHelper.getAllVideoList();
print("Length ${_userList.length}");
notifyListeners();
return _userList;
}
}
enter code here