tsacdop-podcast-app-android/lib/home/download_list.dart

import 'package:flutter/material.dart';
import 'package:flutter_downloader/flutter_downloader.dart';
import 'package:provider/provider.dart';

import '../episodes/episode_detail.dart';
import '../state/download_state.dart';
import '../util/pageroute.dart';

class DownloadList extends StatefulWidget {
  DownloadList({Key key}) : super(key: key);

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

Widget _downloadButton(EpisodeTask task, BuildContext context) {
  var downloader = Provider.of<DownloadState>(context, listen: false);
  switch (task.status.value) {
    case 2:
      return IconButton(
        icon: Icon(
          Icons.pause_circle_filled,
        ),
        onPressed: () => downloader.pauseTask(task.episode),
      );
    case 4:
      return Row(
        mainAxisSize: MainAxisSize.min,
        children: <Widget>[
          IconButton(
            icon: Icon(Icons.refresh, color: Colors.red),
            onPressed: () => downloader.retryTask(task.episode),
          ),
          IconButton(
            icon: Icon(Icons.close),
            onPressed: () => downloader.delTask(task.episode),
          ),
        ],
      );
    case 6:
      return IconButton(
        icon: Icon(Icons.play_circle_filled),
        onPressed: () => downloader.resumeTask(task.episode),
      );
      break;
    default:
      return Center();
  }
}

class _DownloadListState extends State<DownloadList> {
  @override
  Widget build(BuildContext context) {
    return SliverPadding(
      padding: EdgeInsets.zero,
      sliver: Consumer<DownloadState>(builder: (_, downloader, __) {
        var tasks = downloader.episodeTasks
            .where((task) => task.status.value != 3)
            .toList();
        return tasks.length > 0
            ? SliverPadding(
                padding: EdgeInsets.all(5.0),
                sliver: SliverList(
                  delegate: SliverChildBuilderDelegate(
                    (context, index) {
                      return ListTile(
                        onTap: () => Navigator.push(
                          context,
                          ScaleRoute(
                              page: EpisodeDetail(
                            episodeItem: tasks[index].episode,
                          )),
                        ),
                        title: Row(
                          mainAxisSize: MainAxisSize.min,
                          mainAxisAlignment: MainAxisAlignment.start,
                          children: <Widget>[
                            Expanded(
                              flex: 5,
                              child: Container(
                                child: Text(
                                  tasks[index].episode.title,
                                  maxLines: 1,
                                  overflow: TextOverflow.ellipsis,
                                ),
                              ),
                            ),
                            Expanded(
                              flex: 1,
                              child: tasks[index].progress >= 0 &&
                                      tasks[index].status !=
                                          DownloadTaskStatus.failed
                                  ? Container(
                                      width: 40.0,
                                      padding:
                                          EdgeInsets.symmetric(horizontal: 2),
                                      alignment: Alignment.center,
                                      decoration: BoxDecoration(
                                          borderRadius: BorderRadius.all(
                                              Radius.circular(6)),
                                          color: Colors.red),
                                      child: Text(
                                        '${tasks[index].progress}%',
                                        textAlign: TextAlign.center,
                                        maxLines: 1,
                                        style: TextStyle(color: Colors.white),
                                      ))
                                  : Container(),
                            ),
                          ],
                        ),
                        subtitle: SizedBox(
                          height: 2,
                          child: LinearProgressIndicator(
                            value: tasks[index].progress / 100,
                          ),
                        ),
                        leading: CircleAvatar(
                            backgroundImage: tasks[index].episode.avatarImage),
                        trailing: _downloadButton(tasks[index], context),
                      );
                    },
                    childCount: tasks.length,
                  ),
                ),
              )
            : SliverToBoxAdapter(
                child: Center(),
              );
      }),
    );
  }
}