问题描述
在编写应用程序时，我想使应用程序栏和底部导航栏不可滚动，但是当我使用滚动视图时，出现了错误。查看代码：
import 'package:CovidTraces/CustomGridview.dart';
import 'package:CovidTraces/customnavbar.dart';
import 'package:flutter/material.dart';
import 'customappbar.dart';
class HomePage extends StatelessWidget {
@override
Widget build(BuildContext context) {
return SafeArea(
child: Scaffold(
body: Column(
children: [
CustomAppBar(),SingleChildScrollView(
child: Column(
children: [
MyCustomGridview(),],),bottomNavigationBar: MyCustomNavBar(),);
}
}
这给我一个错误
SingleChildScrollView
lib\home.dart:14
════════════════════════════════════════════════════════════════════════════════
Another exception was thrown: RenderBox was not laid out: RenderCustomPaint#834e2 relayoutBoundary=up3 NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
════════ Exception caught by rendering library ═════════════════════════════════
RenderBox was not laid out: RenderCustomPaint#834e2 relayoutBoundary=up3 NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
'package:flutter/src/rendering/box.dart':
Failed assertion: line 1702 pos 12: 'hasSize'
The relevant error-causing widget was
SingleChildScrollView
lib\home.dart:14
════════════════════════════════════════════════════════════════════════════════
Another exception was thrown: RenderBox was not laid out: RenderRepaintBoundary#faba4 relayoutBoundary=up2 NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
════════ Exception caught by rendering library ═════════════════════════════════
RenderBox was not laid out: RenderRepaintBoundary#faba4 relayoutBoundary=up2 NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
'package:flutter/src/rendering/box.dart':
Failed assertion: line 1702 pos 12: 'hasSize'
The relevant error-causing widget was
Column
lib\home.dart:11
════════════════════════════════════════════════════════════════════════════════
Another exception was thrown: RenderBox was not laid out: RenderRepaintBoundary#faba4 relayoutBoundary=up2 NEEDS-PAINT
════════ Exception caught by rendering library ═════════════════════════════════
RenderBox was not laid out: RenderRepaintBoundary#faba4 relayoutBoundary=up2 NEEDS-PAINT
'package:flutter/src/rendering/box.dart':
Failed assertion: line 1702 pos 12: 'hasSize'
The relevant error-causing widget was
Column
...还有更多类似的东西 您能识别出这一点并帮助我将gridview用作scrollview吗？
这是自定义应用栏
import 'package:CovidTraces/CustomGridview.dart';
import 'package:flutter/material.dart';
import 'constraints.dart';
Constraints color = new Constraints();
class CustomAppBar extends StatelessWidget {
Widget IconsContainer(String imgsrc,String message) {
return InkWell(
onTap: () {
print('$message');
},child: Container(
height: 55.0,width: 70.0,decoration: new BoxDecoration(
color: color.primary,shape: BoxShape.circle,child: Padding(
padding: const EdgeInsets.all(10.0),child: Image.asset(
'$imgsrc',);
}
@override
Widget build(BuildContext context) {
double height = MediaQuery.of(context).size.height;
double width = MediaQuery.of(context).size.width;
return Column(
children: [
Padding(
padding: const EdgeInsets.all(8.0),child: Row(
children: [
IconsContainer('assets/images/menu.png','menu clicked...'),Spacer(),Text(
'CoVID TRACES',style: TextStyle(
color: color.writingHead,fontSize: 25.0,fontFamily: 'Poppins',fontWeight: FontWeight.bold,IconsContainer('assets/images/refresh.png','refreshing...'),SingleChildScrollView(
child: Column(
children: [
Stack(
overflow: Overflow.visible,children: [
CustomPaint(
painter: MyCustomPainter(),child: ClipPath(
clipper: MyCustomClip(),child: Container(
decoration: new BoxDecoration(
gradient: new LinearGradient(
begin: Alignment.topLeft,end: Alignment.bottomRight,colors: [
color.custombarG1,color.custombarG2,height: height / 2 - 50,width: width,Positioned(
left: -40.0,top: 10.0,child: Image.asset(
'assets/images/covid3.png',height: 310.0,Align(
alignment: Alignment.topRight,child: Padding(
padding: const EdgeInsets.only(top: 20.0,right: 2.0),child: Column(
crossAxisAlignment: CrossAxisAlignment.end,children: [
Text(
'CoVID-19',style: TextStyle(
color: color.writingTitle,fontSize: 40.0,Padding(
padding: const EdgeInsets.all(3.0),child: Text(
'TRACKER',style: TextStyle(
color: color.primary,fontSize: 30.0,fontStyle: FontStyle.italic,height: 1.2,Padding(
padding: const EdgeInsets.only(right: 40),child: Text(
'+',style: TextStyle(
color: color.writingHead,fontSize: 35.0,height: 0.75,Padding(
padding: const EdgeInsets.only(right: 12.0),child: Text(
'CASES',style: TextStyle(
color: color.writingTitle,Text(
'IN SECONDS',style: TextStyle(
color: color.writingSubHead,height: 1.5,Text(
'WorldWide',height: 3.5,Container(
height: 200,child: GridView.count(
scrollDirection: Axis.vertical,crossAxisCount: 2,children: List.generate(50,(index) {
return Container(
// color: color.primary,child: Card(
color: color.primary,);
}),);
}
}
class MyCustomClip extends CustomClipper<Path> {
@override
Path getClip(Size size) {
Path path = new Path();
path.lineTo(0.0,size.height - 80);
var firstCPoint = new Offset((size.width / 4) - 20,(size.height) / 2 - 50);
var firstEPoint = new Offset((size.width / 2 + 30),size.height - 70);
path.quadraticBezierTo(
firstCPoint.dx,firstCPoint.dy,firstEPoint.dx,firstEPoint.dy);
var secondCPoint = new Offset(size.width * 0.9,size.height + 60);
var secondEPoint = new Offset(size.width,size.height / 2 + 50);
path.quadraticBezierTo(
secondCPoint.dx,secondCPoint.dy,secondEPoint.dx,secondEPoint.dy);
path.lineTo(size.width,0.0);
path.close();
return path;
}
@override
bool shouldReclip(CustomClipper<Path> oldClipper) {
return false;
}
}
class MyCustomPainter extends CustomPainter {
@override
void paint(Canvas canvas,Size size) {
Path path = new Path();
path.lineTo(0.0,0.0);
path.close();
canvas.drawShadow(path,30.0,false);
}
@override
bool shouldRepaint(CustomPainter oldDelegate) {
return true;
}
}
这是自定义导航栏
import 'package:CovidTraces/customappbar.dart';
import 'package:curved_navigation_bar/curved_navigation_bar.dart';
import 'package:flutter/material.dart';
class MyCustomNavBar extends StatefulWidget {
@override
_MyCustomNavBarState createState() => _MyCustomNavBarState();
}
class _MyCustomNavBarState extends State<MyCustomNavBar> {
@override
Widget build(BuildContext context) {
return CurvedNavigationBar(
height: 50.0,index: 2,color: color.primary,animationCurve: Curves.easeInCubic,backgroundColor: Colors.transparent,animationDuration: new Duration(
milliseconds: 200,items: [
Image.asset(
'assets/images/add.png',height: 30.0,width: 30.0,Image.asset(
'assets/images/about.png',Image.asset(
'assets/images/home.png',Image.asset(
'assets/images/contact.png',Image.asset(
'assets/images/chat.png',);
}
}
解决方法
暂无找到可以解决该程序问题的有效方法，小编努力寻找整理中！
如果你已经找到好的解决方法，欢迎将解决方案带上本链接一起发送给小编。
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