Flutter 颤振ListView和ListView.builder问题
我是Flatter的初学者,我创建了一个显示玩家信息的小部件,我使用了ListView和ListView.builder,但我有一个uknown错误,错误是:断言失败:第1785行位置12:“hasSize” 我不知道这个错误的来源是什么,它只是在我添加ListView构建器时开始的,在我添加它之前,一切都正常 以下是我尝试过的:Flutter 颤振ListView和ListView.builder问题,flutter,dart,Flutter,Dart,我是Flatter的初学者,我创建了一个显示玩家信息的小部件,我使用了ListView和ListView.builder,但我有一个uknown错误,错误是:断言失败:第1785行位置12:“hasSize” 我不知道这个错误的来源是什么,它只是在我添加ListView构建器时开始的,在我添加它之前,一切都正常 以下是我尝试过的: import 'package:flutter/material.dart'; import 'package:tl_fantasy/widgets/Player_W
import 'package:flutter/material.dart';
import 'package:tl_fantasy/widgets/Player_Widget.dart';
import 'player_arguments.dart';
class PlayerDetails extends StatelessWidget {
@override
Widget build(BuildContext context) {
final PlayerArguments args = ModalRoute.of(context).settings.arguments;
List<Stats> stats = [
Stats("Matches", args.matches ),
Stats("Goals", args.goals ),
Stats("Assists", args.assists ),
Stats("Saves", args.saves ),
];
List<Team> teams = [
Team("Barcelona B", "https://i.pinimg.com/originals/ef/9c/3f/ef9c3fccec423f70376fcafa05c5d447.jpg","1998" ),
Team("Barcelona", "https://i.pinimg.com/originals/ef/9c/3f/ef9c3fccec423f70376fcafa05c5d447.jpg","2005" ),
];
return Scaffold(
appBar: AppBar(
title: Text("Player Details"),
backgroundColor: Colors.blue[300],
elevation: 0.0,
),
body: Container(
decoration: BoxDecoration(
gradient: LinearGradient(
begin: Alignment.centerLeft,
end: Alignment.centerRight,
colors: [Colors.purple, Colors.blue])
),
child: Container(
decoration: BoxDecoration(
gradient: LinearGradient(
begin: Alignment.topLeft,
end: Alignment.bottomRight,
colors: [Colors.purple, Colors.black38])),
child: ListView(
children: [
SizedBox(
height: 20,
),
Container(
width: double.infinity,
child: Card(
elevation: 4.0,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(10.0),
),
child: Padding(
padding: const EdgeInsets.all(16.0),
child:
Row(
children: <Widget>[
CircleAvatar(
backgroundImage: NetworkImage(args.image),
),
const SizedBox(width:10.0),
Spacer(),
Column(
crossAxisAlignment: CrossAxisAlignment.end,
children: <Widget> [
Text(args.name, style: TextStyle( fontWeight:FontWeight.bold,
fontSize: 18.0,
)),
const SizedBox(height: 5.0, ),
Text(args.club, style: TextStyle( fontWeight:FontWeight.bold,
fontSize: 18.0,
)),
const SizedBox(height: 5.0, ),
Text("Role : "+args.role, style: TextStyle( fontWeight:FontWeight.bold,
fontSize: 18.0, color: Colors.grey[600],
)),
const SizedBox(height: 5.0, ),
Text("Position : "+args.club, style: TextStyle( fontWeight:FontWeight.bold,
fontSize: 18.0, color: Colors.grey[600],
)),
const SizedBox(height: 5.0, ),
Text("Nationality : "+args.nationality, style: TextStyle( fontWeight:FontWeight.bold,
fontSize: 18.0, color: Colors.grey[600],
)),
],
),
],
),
),
),
),
Container(
padding: EdgeInsets.all(12.0),
child: GridView.builder(
shrinkWrap: true,
itemCount: stats.length,
gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
crossAxisCount: 2,
crossAxisSpacing: 4.0,
mainAxisSpacing: 4.0
),
itemBuilder: (BuildContext context, int index){
return Card(
child: Center(
child: Column(
crossAxisAlignment: CrossAxisAlignment.center,
children: <Widget>[
Container(
alignment: Alignment.topCenter,
padding: EdgeInsets.fromLTRB(0, 5, 0, 0),
child: Text(stats[index].result,style: TextStyle(fontSize: 20.0)),
),
Container(
alignment: Alignment.bottomCenter,
child: Text(stats[index].title,style: TextStyle(fontSize: 25.0)),),
]
),
),
);
},
)
),
SizedBox(
height: 30,
),
Container(child:
ListView.builder(
itemBuilder: (context, index){
return Card(
elevation: 4.0,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(10.0),
),
child: Padding(
padding: const EdgeInsets.all(16.0),
child:
Row(
children: <Widget>[
CircleAvatar(
backgroundImage: NetworkImage(teams[index].image),
),
const SizedBox(width:10.0),
Spacer(),
Column(
crossAxisAlignment: CrossAxisAlignment.end,
children: <Widget> [
Text(teams[index].name, style: TextStyle( fontWeight:FontWeight.bold,
fontSize: 18.0,
)),
const SizedBox(height: 5.0, ),
Text("joined : "+teams[index].date, style: TextStyle( fontWeight:FontWeight.bold,
fontSize: 18.0, color: Colors.grey[600],
)),
],
),
],
),
),
);
},
itemCount: teams.length,
),),
],
),
),
),
);
}
}
class Stats{
String title;
String result;
Stats(this.title,this.result);
}
class Team {
String name;
String image;
String date;
Team(this.name,this.image,this.date);
}
导入“包装:颤振/材料.省道”;
导入“package:tl_fantasy/widgets/Player_Widget.dart”;
导入“player_arguments.dart”;
类PlayerDetails扩展了无状态小部件{
@凌驾
小部件构建(构建上下文){
final PlayerArguments args=ModalRoute.of(context.settings.arguments);
列表统计=[
统计数据(“匹配”,args.Matches),
统计数据(“目标”,args.Goals),
统计数据(“助攻”,args.assesss),
统计数据(“保存”,args.Saves),
];
名单小组=[
“巴塞罗那B队”https://i.pinimg.com/originals/ef/9c/3f/ef9c3fccec423f70376fcafa05c5d447.jpg","1998" ),
“巴塞罗那队”https://i.pinimg.com/originals/ef/9c/3f/ef9c3fccec423f70376fcafa05c5d447.jpg","2005" ),
];
返回脚手架(
appBar:appBar(
标题:文本(“玩家详细信息”),
背景颜色:颜色。蓝色[300],
标高:0.0,
),
主体:容器(
装饰:盒子装饰(
梯度:线性梯度(
开始:Alignment.centerLeft,
结束:对齐。中间右侧,
颜色:[颜色。紫色,颜色。蓝色])
),
子:容器(
装饰:盒子装饰(
梯度:线性梯度(
开始:Alignment.topLeft,
结束:对齐。右下角,
颜色:[colors.purple,colors.black38]),
子:ListView(
儿童:[
大小盒子(
身高:20,
),
容器(
宽度:double.infinity,
孩子:卡片(
标高:4.0,
形状:圆形矩形边框(
边界半径:边界半径。圆形(10.0),
),
孩子:填充(
填充:常数边集全部(16.0),
儿童:
划船(
儿童:[
圆形(
背景图像:NetworkImage(args.image),
),
常量大小框(宽度:10.0),
垫片(),
纵队(
crossAxisAlignment:crossAxisAlignment.end,
儿童:[
Text(args.name,style:TextStyle(fontwweight:fontwweight.bold,
字体大小:18.0,
)),
const SizedBox(高度:5.0,),
文本(args.club,样式:TextStyle),
字体大小:18.0,
)),
const SizedBox(高度:5.0,),
Text(“角色:”+args.Role,样式:TextStyle(fontWeight:fontWeight.bold,
fontSize:18.0,颜色:Colors.灰色[600],
)),
const SizedBox(高度:5.0,),
Text(“位置:”+args.club,样式:TextStyle(fontWeight:fontWeight.bold,
fontSize:18.0,颜色:Colors.灰色[600],
)),
const SizedBox(高度:5.0,),
Text(“国籍:”+args.national,样式:TextStyle(fontWeight:fontWeight.bold,
fontSize:18.0,颜色:Colors.灰色[600],
)),
],
),
],
),
),
),
),
容器(
填充:所有边缘设置(12.0),
子项:GridView.builder(
收缩膜:对,
itemCount:stats.length,
gridDelegate:SliverGridDelegateWithFixedCrossAxisCount(
交叉轴计数:2,
交叉轴间距:4.0,
主轴间距:4.0
),
itemBuilder:(构建上下文,int索引){
回程卡(
儿童:中心(
子:列(
crossAxisAlignment:crossAxisAlignment.center,
儿童:[
容器(
对齐:alignment.topCenter,
填充:从LTRB(0,5,0,0)开始的边缘设置,
子项:文本(统计信息[索引])。结果,样式:TextStyle(fontSize:20.0)),
),
容器(
对齐:对齐.bottomCenter,
子项:文本(统计信息[索引])。标题,样式:TextStyle(fontSize:25.0)),
]
),
),
);
},
)
),
大小盒子(
身高:30,
),
容器(子容器:
ListView.builder(
itemBuilder:(上下文,索引){
回程卡(
标高:4.0,
形状:圆形矩形边框(
边界半径:边界半径。圆形(10.0),
),
孩子:填充(
衬垫
Container(
height: //your parameter,
width: //your parameter,
child:
ListView.builder(
itemBuilder: (context, index){
return Card(
elevation: 4.0,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(10.0),
),
child: Padding(
padding: const EdgeInsets.all(16.0),
child:
Row(
children: <Widget>[
CircleAvatar(
backgroundImage: NetworkImage(teams[index].image),
),
const SizedBox(width:10.0),
Spacer(),
Column(
crossAxisAlignment: CrossAxisAlignment.end,
children: <Widget> [
Text(teams[index].name, style: TextStyle( fontWeight:FontWeight.bold,
fontSize: 18.0,
)),
const SizedBox(height: 5.0, ),
Text("joined : "+teams[index].date, style: TextStyle( fontWeight:FontWeight.bold,
fontSize: 18.0, color: Colors.grey[600],
)),
],
),
],
),
),
);
},
itemCount: teams.length,
),),
Column(
children: [
Expanded(
child: ListView.builder(
itemBuilder: (context, index) {
return Card(
elevation: 4.0,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(10.0),
),
child: Padding(
padding: const EdgeInsets.all(16.0),
child: Row(
children: <Widget>[
CircleAvatar(
backgroundImage: NetworkImage(teams[index].image),
),
const SizedBox(width: 10.0),
Spacer(),
Column(
crossAxisAlignment: CrossAxisAlignment.end,
children: <Widget>[
Text(teams[index].name,
style: TextStyle(
fontWeight: FontWeight.bold,
fontSize: 18.0,
)),
const SizedBox(
height: 5.0,
),
Text("joined : " + teams[index].date,
style: TextStyle(
fontWeight: FontWeight.bold,
fontSize: 18.0,
color: Colors.grey[600],
)),
],
),
],
),
),
);
},
itemCount: teams.length,
),
),
],
);