一统天下 flutter - widget 列表类: Dismissible - 滑动删除
示例如下:
lib\widget\list\dismissible.dart
/*
* Dismissible - 滑动删除
*
* 支持左滑/右滑/上滑/下滑删除,一般在列表中使用,当然也可以不依托列表使用
*/
import 'package:flutter/material.dart';
import '../../helper.dart';
class DismissibleDemo extends StatefulWidget {
const DismissibleDemo({Key? key}) : super(key: key);
@override
_DismissibleDemoState createState() => _DismissibleDemoState();
}
class _DismissibleDemoState extends State<DismissibleDemo> {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: const Text("title")),
backgroundColor: Colors.orange,
body: const _MyWidget(),
);
}
}
class _MyWidget extends StatefulWidget {
const _MyWidget({super.key});
@override
_MyWidgetState createState() => _MyWidgetState();
}
class _MyWidgetState extends State<_MyWidget> {
List<int> items = List<int>.generate(100, (int index) => index);
@override
Widget build(BuildContext context) {
return ListView.builder(
itemCount: items.length,
itemBuilder: (BuildContext context, int index) {
return Dismissible(
/// 必须要指定 key
key: ValueKey<int>(items[index]),
/// 滑动删除支持的滑动方向(vertical, horizontal, endToStart, startToEnd, up, down, none)
direction: DismissDirection.horizontal,
/// 正常状态下显示的内容
child: ListTile(
title: MyText('item ${items[index]}',),
),
/// item 的背景内容(右滑删除操作时)
background: Container(
color: Colors.red,
alignment: Alignment.centerLeft,
child: const MyTextSmall("右滑删除"),
),
/// item 的背景内容(左滑删除操作时)
secondaryBackground: Container(
color: Colors.green,
alignment: Alignment.centerRight,
child: const MyTextSmall("左滑删除"),
),
/// 滑动删除时,item 的偏移系数(偏移量为偏移系数 * item 的高)
crossAxisEndOffset: 0.0,
/// 删除前的回调,用于确认是否真的删除
confirmDismiss: (DismissDirection direction) async {
var result = await showDialog(
context: context,
builder: (BuildContext context) {
return AlertDialog(
content: const Text("确认删除吗?"),
actions: <Widget>[
ElevatedButton(
onPressed: () => Navigator.of(context).pop(true),
child: const Text("删除"),
),
ElevatedButton(
onPressed: () => Navigator.of(context).pop(false),
child: const Text("取消"),
),
],
);
},
);
/// 返回 true 则会触发 onDismissed() 回调
return result;
},
/// 删除后的回调
onDismissed: (DismissDirection direction) {
setState(() {
items.removeAt(index);
});
},
/// 删除后,删除项的下面的项会移上来,这里用于设置这个动画的时长
resizeDuration: const Duration(milliseconds: 300),
/// 删除后,删除项的下面的项会移上来,这个动画效果的每一帧都会触发这个事件
onResize: () {
/// log("onResize");
},
/// 滑动的进度发生变化时会触发此事件
onUpdate: (DismissUpdateDetails details) {
log("onUpdate, progress:${details.progress}, reached:${details.reached}");
},
/// 滑动删除动画的时长(快速惯性滑动时此值无效)
movementDuration: const Duration(milliseconds: 200),
/// 用于指定拖动到什么程度时触发 onDismissed
dismissThresholds: const {
DismissDirection.startToEnd: 0.8, /// 右滑时,在超过 80% 的位置松开手则会触发 onDismissed(快速惯性滑动时此值无效)
DismissDirection.endToStart: 0.3 /// 左滑时,在超过 30% 的位置松开手则会触发 onDismissed(快速惯性滑动时此值无效)
},
);
},
);
}
}
标签:index,widget,const,key,删除,Dismissible,context,滑动,flutter From: https://www.cnblogs.com/webabcd/p/flutter_lib_widget_list_dismissible.html