Flutter 实现网易云音乐字幕的代码

loadData() async {
 var jsonStr =
 await DefaultAssetBundle.of(context).loadString('assets/subtitle.txt');
 var list = jsonStr.split(RegExp('\n'));
 list.forEach((f) {
 if (f.isNotEmpty) {
 var r = f.split(RegExp(' '));
 if (r.length >= 2) {
 _subtitleList.add(SubtitleEntry(r[0], r[1]));
 }
 }
 });
 setState(() {});
}

@override
Widget build(BuildContext context) {
 return Scaffold(
 appBar: AppBar(
 title: Text('弹幕'),
 ),
 body: Stack(
 children: <Widget>[
 Positioned.fill(
  child: Image.asset(
  'assets/imgs/background.png',
  fit: BoxFit.cover,
 )),
 Positioned.fill(
  child: Subtitle(
  _subtitleList,
  selectedTextStyle: TextStyle(color: Colors.white,fontSize: 18),
  unSelectedTextStyle: TextStyle(
  color: Colors.black.withOpacity(.6),
  ),
  diameterRatio: 5,
  itemExtent: 45,
 ))
 ],
 ),
 );
}

@override
Widget build(BuildContext context) {
 if (widget.data == null || widget.data.length == 0) {
 return Container();
 }
 return ListWheelScrollView.useDelegate(
 controller: _controller,
 diameterRatio: widget.diameterRatio,
 itemExtent: widget.itemExtent,
 childDelegate: ListWheelChildBuilderDelegate(
 builder: (context, index) {
  return Container(
  alignment: Alignment.center,
  child: Text(
  '${widget.data[index].content}',
  style: _currentIndex == index
   ? widget.selectedTextStyle
   : widget.unSelectedTextStyle,
  ),
  );
 },
 childCount: widget.data.length),
 );
}

Subtitle(
	_subtitleList,
	selectedTextStyle: TextStyle(color: Colors.white,fontSize: 18),
	unSelectedTextStyle: TextStyle(
 	color: Colors.black.withOpacity(.6),
	)
)

Subtitle(
	_subtitleList,
	diameterRatio: 5,
)