flutter - Flutter在PageViewer的每个页面中初始化不同的[just-audio] Player？

Question

我需要在 PageViewer 中使用 JustAudio Player。每次我滑动到不同的页面时，我都需要一个不同的 URL 才能在 JustAudio Player 中播放。我正在使用 Suragch 的 PageManager 来处理 Flutter 的 JustAudio PLayer 的滑块。

https://github.com/suragch/streaming_audio_flutter_demo/blob/master/lib/page_manager.dart

这是 PageView 生成器；

class _StageBuilderState extends State<StageBuilder> {

  late PageManager _pageManager;

  @override
  void initState() {
    super.initState();
    _pageManager = PageManager();
  }

  @override
  void dispose() {
    _pageManager.dispose();
    super.dispose();
  }

  @override
  Widget build(context) {
    return
      PageView.builder(
        itemCount: widget.speakcrafts.length,
        itemBuilder: (context, int currentIndex) {
          return createViewItem(widget.speakcrafts[currentIndex], context, currentIndex, widget.speakcrafts.length );
        },
       );
  }

  Widget createViewItem(AudioContent speakcraft, BuildContext context, int currentIndex, int currentlength) {

    String kUrl = speakcraft.audioname!;
    _pageManager = PageManager(url:kUrl);

    return Column(
      children: [
        ValueListenableBuilder<ButtonState>(
          valueListenable: _pageManager.buttonNotifier,
          builder: (_, value, __) {
            switch (value) {
              case ButtonState.loading:
                return Container(
                  margin: EdgeInsets.all(8.0),
                  width: 160.0,
                  height: 160.0,
                  child: CircularProgressIndicator(),
                );
              case ButtonState.paused:
                return IconButton(
                  icon: Icon(Icons.play_arrow),                  
                  onPressed: _pageManager.play,
                );
              case ButtonState.playing:
                return IconButton(
                  icon: Icon(Icons.pause),                  
                  onPressed: _pageManager.pause,
                );
            }
          },
        ),
        ValueListenableBuilder<ProgressBarState>(
          valueListenable: _pageManager.progressNotifier,
          builder: (_, value, __) {
            return ProgressBar(
                progress: value.current,
                buffered: value.buffered,
                total: value.total,
                onSeek: _pageManager.seek                
            );
          },
        ),
      ],
    );
  }
}

但是 Flutter 抱怨 Player 已经被初始化了；

LateInitializationError: Field '_pageManager@102518713' has already been initialized.

我试着改变这个；

_pageManager = PageManager(url:kUrl);

对此；

 PageManager(url:kUrl);

但它没有播放。

那么如何将不同的 URL 传递给 PageView 中的播放器呢？

标签： flutterdartflutter-pageviewjust-audio