flatter:获取json固定数据并按字母顺序排序
我从一个数据库中获取数据。并希望显示我的应用程序,其中数据的类别等于1。我可以通过调用category-1 url链接来实现这一点,但我需要一次按链接获取所有数据,然后将其分为许多部分 我正在使用flatter:获取json固定数据并按字母顺序排序,json,api,sorting,flutter,where-clause,Json,Api,Sorting,Flutter,Where Clause,我从一个数据库中获取数据。并希望显示我的应用程序,其中数据的类别等于1。我可以通过调用category-1 url链接来实现这一点,但我需要一次按链接获取所有数据,然后将其分为许多部分 我正在使用if(mydata[index].category==1)然后返回。但我认为这是一种错误的划分方式。它显示了错误的输出 我还想按字母顺序对这些数据进行排序 这是我的密码- import 'package:boimarket/booksdescription.dart'; import 'package:
if(mydata[index].category==1)
然后返回。但我认为这是一种错误的划分方式。它显示了错误的输出
我还想按字母顺序对这些数据进行排序
这是我的密码-
import 'package:boimarket/booksdescription.dart';
import 'package:boimarket/model/model.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;
import 'package:draggable_scrollbar/draggable_scrollbar.dart';
class StoryBooksCategory extends StatefulWidget {
final ScrollController controller;
final List<Book> storybooks;
StoryBooksCategory({Key key, @required this.controller, this.storybooks})
: super(key: key);
@override
_StoryBooksCategoryState createState() => _StoryBooksCategoryState();
}
class _StoryBooksCategoryState extends State<StoryBooksCategory> {
@override
void initState() {
super.initState();
}
@override
Widget build(BuildContext context) {
var _height = MediaQuery.of(context).size.height;
var _width = MediaQuery.of(context).size.width;
final Color _whiteCream = Color.fromRGBO(250, 245, 228, 1);
final Color _darkBlue = Color.fromRGBO(0, 68, 69, 1);
return Align(
alignment: Alignment.topCenter,
child: Container(
width: _width / 1.1,
child: FutureBuilder(
future: fetchBooks(),
builder: (context, snapshot) {
if (!snapshot.hasData) {
return Column(
mainAxisAlignment: MainAxisAlignment.center,
crossAxisAlignment: CrossAxisAlignment.center,
children: <Widget>[
LinearProgressIndicator(
backgroundColor: _whiteCream,
),
Text("Loading"),
],
);
} else if (snapshot.hasData) {
var mydata = snapshot.data;
return DraggableScrollbar.rrect(
controller: widget.controller,
backgroundColor: _darkBlue,
child: ListView.builder(
controller: widget.controller,
scrollDirection: Axis.vertical,
itemCount: mydata.length,
itemBuilder: (context, index) {
if (mydata[index].category == 1)
return GestureDetector(
onTap: () {
Route route = MaterialPageRoute(
builder: (context) =>
BookDescription(storyBooksValue: mydata[index]),
);
Navigator.push(context, route);
},
child: Padding(
padding: const EdgeInsets.only(
left: 10.0, right: 10.0, top: 20.0),
child: Container(
width: _width / 1.1,
height: _height / 4,
decoration: BoxDecoration(
color: _whiteCream,
borderRadius: BorderRadius.all(
Radius.circular(5.0),
),
boxShadow: [
BoxShadow(
color: Colors.black26,
blurRadius: 2,
spreadRadius: 2,
offset: Offset(2.0, 2.0),
)
]),
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: <Widget>[
Flexible(
flex: 4,
child: Padding(
padding: const EdgeInsets.all(10.0),
child: Card(
elevation: 10.0,
child: ClipRRect(
borderRadius:
BorderRadius.circular(5.0),
child: FadeInImage.assetNetwork(
fadeOutCurve: Curves.easeInCubic,
placeholder:
'assets/images/bookshelf.jpg',
image: mydata[index].imgUrl == null
? 'assets/images/bookshelf.jpg'
: mydata[index].imgUrl,
fit: BoxFit.cover,
),
),
),
),
),
Flexible(
flex: 6,
child: Column(
crossAxisAlignment:
CrossAxisAlignment.center,
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Row(
children: <Widget>[
Text(
"বইয়ের নামঃ ",
style: TextStyle(
fontWeight: FontWeight.bold),
),
Flexible(
child: Text(
"${mydata[index].name}",
overflow: TextOverflow.fade,
),
),
],
),
Row(
children: <Widget>[
Text(
"লেখকঃ ",
style: TextStyle(
fontWeight: FontWeight.bold),
),
Flexible(
child: Text(
"${mydata[index].author}",
overflow: TextOverflow.ellipsis,
),
),
],
),
Row(
children: <Widget>[
Text(
"বইয়ের ধরণঃ ",
style: TextStyle(
fontWeight: FontWeight.bold),
),
Flexible(
child: Text(
"${mydata[index].genreClass}",
overflow: TextOverflow.ellipsis,
),
),
],
),
],
),
),
],
),
),
),
);
},
),
);
} else {
return Column(
mainAxisAlignment: MainAxisAlignment.center,
crossAxisAlignment: CrossAxisAlignment.center,
children: <Widget>[
Icon(Icons.error_outline),
Text("Somthing Went to wrong"),
],
);
}
},
),
),
);
}
}
import'包装:boimarket/booksdescription.dart';
进口“包装:boimarket/model/model.dart”;
进口“包装:颤振/基础.dart”;
进口“包装:颤振/材料.省道”;
将“package:http/http.dart”导入为http;
导入“package:draggable_scrollbar/draggable_scrollbar.dart”;
类StoryBooksCategory扩展了StatefulWidget{
最终滚动控制器;
最后列出故事书;
StoryBooksCategory({Key,@required this.controller,this.storybooks})
:super(key:key);
@凌驾
_StoryBooksCategoryState createState()=>\u StoryBooksCategoryState();
}
类_StoryBooksCategoryState扩展状态{
@凌驾
void initState(){
super.initState();
}
@凌驾
小部件构建(构建上下文){
var\u height=MediaQuery.of(context).size.height;
var _width=MediaQuery.of(context).size.width;
最终颜色_whiteCream=颜色。来自RGBO(2502452281);
最终颜色_darkBlue=Color.fromRGBO(0,68,69,1);
返回对齐(
对齐:alignment.topCenter,
子:容器(
宽度:_宽度/1.1,
孩子:未来建设者(
future:fetchBooks(),
生成器:(上下文,快照){
如果(!snapshot.hasData){
返回列(
mainAxisAlignment:mainAxisAlignment.center,
crossAxisAlignment:crossAxisAlignment.center,
儿童:[
线性预测指示器(
背景颜色:_whiteCream,
),
文本(“加载”),
],
);
}else if(snapshot.hasData){
var mydata=snapshot.data;
返回DragableScrollbar.rect(
控制器:widget.controller,
背景色:_深蓝色,
子项:ListView.builder(
控制器:widget.controller,
滚动方向:轴垂直,
itemCount:mydata.length,
itemBuilder:(上下文,索引){
if(mydata[index].category==1)
返回手势检测器(
onTap:(){
路线=物料管理路线(
生成器:(上下文)=>
BookDescription(StoryBookValue:mydata[索引]),
);
推送(上下文、路线);
},
孩子:填充(
填充:仅限常量边设置(
左:10.0,右:10.0,顶:20.0),
子:容器(
宽度:_宽度/1.1,
高度:_高度/4,
装饰:盒子装饰(
颜色:白色奶油,
borderRadius:borderRadius.all(
圆形半径(5.0),
),
boxShadow:[
箱形阴影(
颜色:颜色。黑色,
半径:2,
扩展半径:2,
偏移量:偏移量(2.0,2.0),
)
]),
孩子:排(
mainAxisAlignment:mainAxisAlignment.space,
儿童:[
灵活的(
弹性:4,
孩子:填充(
填充:常数边集全部(10.0),
孩子:卡片(
标高:10.0,
孩子:ClipRRect(
边界半径:
边界半径。圆形(5.0),
子项:FadeInImage.assetNetwork(
淡出曲线:曲线。淡出曲线,
占位符:
“资产/图像/书架.jpg”,
图像:mydata[index].imgUrl==null
?“资产/图像/书架.jpg”
:mydata[index].imgUrl,
适合:BoxFit.cover,
),
),
),
),
),
灵活的(
弹性:6,
子:列(
横轴对齐:
交叉轴对齐。中心,
mainAxisAlignment:mainAxisAlignment.center,
儿童:[
划船(
儿童:[
正文(
"বইয়ের নামঃ ",
var books = await fetchBooks();
var cat1books = books.where((b) => b.category == 1).toList();
var mydata = snapshot.data.where((b) => b.category == 1).toList();
mydata.sort((a, b) => a.name.compareTo(b.name));