我一直在研究和尝试做一些项目和堆栈在这方面。所以,我创建了自定义滚动视图和sliverappbar必须要么完全打开或完全关闭。我尝试这样做,但有问题的动画滚动。
import 'package:flutter/material.dart';
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: Scaffold(
appBar: AppBar(
backgroundColor: Colors.deepPurple,
),
body: const MyHomePage(),
),
);
}
}
class MyHomePage extends StatefulWidget {
const MyHomePage({Key? key}) : super(key: key);
@override
State<MyHomePage> createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
final _scrollController = ScrollController();
bool isClosed = false;
@override
void initState() {
super.initState();
_scrollController.addListener(() {
if (_scrollController.offset >= 5 && _scrollController.offset <= 200) {
if (isClosed) {
_scrollController.jumpTo(0);
close();
} else {
_scrollController.jumpTo(202);
close();
}
}
});
}
close() {
setState(() {
isClosed = !isClosed;
});
}
@override
Widget build(BuildContext context) {
return CustomScrollView(
controller: _scrollController,
slivers: [
SliverAppBar(
expandedHeight: 200,
flexibleSpace: SizedBox(
child: Container(
height: 200,
decoration: const BoxDecoration(
image: DecorationImage(
image: NetworkImage(
"https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcS5-OgasVpm-kc2HaOUloxKVlLzLuM6Q53mfA&usqp=CAU"),
fit: BoxFit.cover)),
),
),
),
SliverList(
delegate: SliverChildBuilderDelegate(
(BuildContext context, int index) {
return Container(
color: Color(index),
height: 100,
width: MediaQuery.of(context).size.width,
child: Text("$index"),
);
},
childCount: 10,
))
],
);
}
}
使用jumpTo时可以正常工作,但使用animateTo时会出现问题。谢谢!
1条答案
按热度按时间k2fxgqgv1#
您需要将
.animateTo()
Package 在Future delay
中。或者,您也可以在
PostFrameCallback
中进行 Package