flutter_aliplayer/example/lib/widget/aliyun_marqueeview.dart

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import 'package:flutter/cupertino.dart';
class MarqueeView extends StatefulWidget {
final Duration pauseDuration;
///滚动速度单位s
final double scrollSpeed;
final Widget child;
const MarqueeView(
{Key key,
this.pauseDuration = const Duration(milliseconds: 100),
this.scrollSpeed = 100.0,
this.child})
: super(key: key);
@override
_MarqueeViewState createState() => _MarqueeViewState();
}
class _MarqueeViewState extends State<MarqueeView>
with SingleTickerProviderStateMixin {
bool _validFlag = true;
double _boxWidth = 0;
final ScrollController _controller = ScrollController();
@override
void dispose() {
_validFlag = false;
_controller.dispose();
super.dispose();
}
@override
void initState() {
super.initState();
scroll();
}
@override
Widget build(BuildContext context) {
return LayoutBuilder(
builder: (BuildContext context, BoxConstraints constraints) {
_boxWidth = constraints.maxWidth;
return SingleChildScrollView(
// 禁止手动滑动。
physics: const NeverScrollableScrollPhysics(),
controller: _controller,
scrollDirection: Axis.horizontal,
child: Container(
padding: EdgeInsets.symmetric(horizontal: _boxWidth),
child: widget.child,
),
);
},
);
}
void scroll() async {
while (_validFlag) {
await Future.delayed(widget.pauseDuration);
if (_boxWidth <= 0) {
continue;
}
_controller.jumpTo(0);
await _controller.animateTo(_controller.position.maxScrollExtent,
duration: Duration(
seconds: (_controller.position.maxScrollExtent / widget.scrollSpeed).floor(),
),
curve: Curves.easeInToLinear);
}
}
}