Flutter 使用jumpto和sticky_头文件包会导致UI问题
我创建了一个新的颤振项目并添加了这个包 之后,我实现了一个具有ScrollController的列表生成器。 我每隔5秒调用setState 3次,并修改一个全局偏移量变量,该变量将用于构建方法,以将列表跳转到新偏移量(使用SchedulerBinding.instance.addPostFrameCallback) 问题是,在我调用jumpto方法后,标题被弄乱了(如果我手动滚动标题,标题将返回到正常位置) 示例:Flutter 使用jumpto和sticky_头文件包会导致UI问题,flutter,dart,Flutter,Dart,我创建了一个新的颤振项目并添加了这个包 之后,我实现了一个具有ScrollController的列表生成器。 我每隔5秒调用setState 3次,并修改一个全局偏移量变量,该变量将用于构建方法,以将列表跳转到新偏移量(使用SchedulerBinding.instance.addPostFrameCallback) 问题是,在我调用jumpto方法后,标题被弄乱了(如果我手动滚动标题,标题将返回到正常位置) 示例: import 'package:flutter/material.dart';
import 'package:flutter/material.dart';
import 'package:flutter/scheduler.dart';
import 'package:sticky_headers/sticky_headers.dart';
double offset = 0;
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: MyHomePage(),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key}) : super(key: key);
@override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
ScrollController _scrollController = ScrollController();
@override
void initState() {
super.initState();
Future.delayed(Duration(seconds: 5)).then((_) => setState(() {
offset = 3000;
})).then((_) async => await Future.delayed(Duration(seconds: 5))).then((_) => setState(() {
offset = 1000;
})).then((_) async => await Future.delayed(Duration(seconds: 5))).then((_) => setState(() {
offset = 5000;
}));
}
@override
Widget build(BuildContext context) {
SchedulerBinding.instance.addPostFrameCallback((_) {
print(offset);
_scrollController.jumpTo(offset);
});
return Scaffold(body: Container(padding: EdgeInsets.only(top: 20),child: _buildList(context)));
}
Widget _buildList(BuildContext context) {
return NotificationListener<ScrollNotification>(
child: ListView.builder(
controller: _scrollController,
itemCount: 100,
itemBuilder: (BuildContext context, int sectionIndex) => StickyHeader(
header: Container(
height: 50,
alignment: Alignment.center,
color: Colors.blue,
child: Text("$sectionIndex")),
content: ListView.builder(
itemCount: 10,
shrinkWrap: true,
physics: NeverScrollableScrollPhysics(),
itemBuilder: (context, rowIndex) => Container(
color: Colors.white,
child: Text("$sectionIndex"))))),
onNotification: (ScrollNotification scrollNotification) {
offset = _scrollController.offset;
print(offset);
return true;
});
}
}
代码:
import 'package:flutter/material.dart';
import 'package:flutter/scheduler.dart';
import 'package:sticky_headers/sticky_headers.dart';
double offset = 0;
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: MyHomePage(),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key}) : super(key: key);
@override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
ScrollController _scrollController = ScrollController();
@override
void initState() {
super.initState();
Future.delayed(Duration(seconds: 5)).then((_) => setState(() {
offset = 3000;
})).then((_) async => await Future.delayed(Duration(seconds: 5))).then((_) => setState(() {
offset = 1000;
})).then((_) async => await Future.delayed(Duration(seconds: 5))).then((_) => setState(() {
offset = 5000;
}));
}
@override
Widget build(BuildContext context) {
SchedulerBinding.instance.addPostFrameCallback((_) {
print(offset);
_scrollController.jumpTo(offset);
});
return Scaffold(body: Container(padding: EdgeInsets.only(top: 20),child: _buildList(context)));
}
Widget _buildList(BuildContext context) {
return NotificationListener<ScrollNotification>(
child: ListView.builder(
controller: _scrollController,
itemCount: 100,
itemBuilder: (BuildContext context, int sectionIndex) => StickyHeader(
header: Container(
height: 50,
alignment: Alignment.center,
color: Colors.blue,
child: Text("$sectionIndex")),
content: ListView.builder(
itemCount: 10,
shrinkWrap: true,
physics: NeverScrollableScrollPhysics(),
itemBuilder: (context, rowIndex) => Container(
color: Colors.white,
child: Text("$sectionIndex"))))),
onNotification: (ScrollNotification scrollNotification) {
offset = _scrollController.offset;
print(offset);
return true;
});
}
}
导入“包装:颤振/材料.省道”;
导入“package:flatter/scheduler.dart”;
导入“package:sticky_headers/sticky_headers.dart”;
双偏移=0;
void main()=>runApp(MyApp());
类MyApp扩展了无状态小部件{
@凌驾
小部件构建(构建上下文){
返回材料PP(
主题:主题数据(
主样本:颜色。蓝色,
),
主页:MyHomePage(),
);
}
}
类MyHomePage扩展StatefulWidget{
MyHomePage({Key}):超级(Key:Key);
@凌驾
_MyHomePageState createState()=>\u MyHomePageState();
}
类_MyHomePageState扩展状态{
ScrollController_ScrollController=ScrollController();
@凌驾
void initState(){
super.initState();
Future.delayed(持续时间(秒数:5))。然后(()=>setState(){
偏移量=3000;
}))。然后(()异步=>等待未来。延迟(持续时间(秒:5))。然后()=>设置状态(){
偏移量=1000;
}))。然后(()异步=>等待未来。延迟(持续时间(秒:5))。然后()=>设置状态(){
偏移量=5000;
}));
}
@凌驾
小部件构建(构建上下文){
SchedulerBinding.instance.addPostFrameCallback((){
印刷(胶印);
_滚动控制器。跳到(偏移);
});
返回脚手架(主体:容器(填充:仅限边集(顶部:20),子项:构建列表(上下文));
}
小部件构建列表(构建上下文){
返回通知侦听器(
子项:ListView.builder(
控制器:\ u滚动控制器,
物品计数:100,
itemBuilder:(BuildContext上下文,int sectionIndex)=>StickyHeader(
标题:容器(
身高:50,
对齐:对齐.center,
颜色:颜色,蓝色,
子项:文本(“$sectionIndex”),
内容:ListView.builder(
物品计数:10,
收缩膜:对,
物理学:NeverscrollableScroll物理学(),
itemBuilder:(上下文,行索引)=>容器(
颜色:颜色,白色,
子项:文本(“$sectionIndex”;”),
onNotification:(滚动通知滚动通知){
偏移量=_scrollController.offset;
印刷(胶印);
返回true;
});
}
}
为什么不问问这个库的作者?我也在他们的git上发布了一个问题。为什么不问问这个库的作者?我也在他们的git上发布了一个问题。