37 lines
923 B
Dart
37 lines
923 B
Dart
/// 返回顶部
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library;
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import 'package:flutter/material.dart';
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class Backtop extends StatelessWidget {
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const Backtop({
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super.key,
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required this.controller,
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required this.offset,
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this.distance = 1000.0,
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});
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final ScrollController controller;
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/// 滚动位置
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final double offset;
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/// 距离顶部多远显示
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final double distance;
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@override
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Widget build(BuildContext context){
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return AnimatedOpacity(
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opacity: offset > distance ? 1.0 : 0.0,
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duration: Duration(milliseconds: 200),
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child: IconButton(
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onPressed: (){
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controller.animateTo(0, duration: Duration(milliseconds: 300), curve: Curves.easeInOut);
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},
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icon: Icon(Icons.arrow_upward_rounded, size: 20.0,),
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style: ButtonStyle(
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backgroundColor: WidgetStateProperty.all(Colors.grey[100]),
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),
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),
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);
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}
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}
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