Flutter實戰視頻-移動電商-26.列表頁_使用Provide控制子類-2

26.列表頁_使用Provide控制子類-2

主要實現功能，點擊一級分類，二級分類跟着變。這裏主要用哦咱們的provide

新建provide

provide文件夾下建立：child_category.dart

 

事件上就是這個實體：BxMallSubDto

 

這樣咱們的Provide類就寫完了。

 

而後在main.dart中註冊provide

import './provide/child_category.dart';

 

 

 

繼續category_page.dart

先引入咱們的provide和childCategory的provide

import 'package:provide/provide.dart';
import '../provide/child_category.dart';

 

 

給左側的類別加事件

左側每一個元素的點擊事件

 

右側的小分類

 

移動過來之後呢，這裏就報錯了，由於咱們的list已經註釋帶掉了不用了。

 

 

效果展現

點擊左側大類會顯示右側的小類別

 

增長點擊的左側大類，高亮效果

咱們用setState去解決這個問題

 

最終展現效果

 

 

最終代碼

provide/child_category.dart

import 'package:flutter/material.dart';
import '../model/category.dart';

class ChildCategory with ChangeNotifier{
 List<BxMallSubDto> childCategoryList=[];
  
  getChildCategory(List list)
  {
    childCategoryList=list;
    notifyListeners();//監聽
  }
}

 

lib/main.dart

import 'package:flutter/material.dart';
import './pages/index_page.dart';
import 'package:provide/provide.dart';
import './provide/counter.dart';
import './provide/child_category.dart';


void main(){
 var counter=Counter();
 var providers=Providers();
 var childCategory=ChildCategory();
 //註冊 依賴
 providers
 ..provide(Provider<Counter>.value(counter))
 ..provide(Provider<ChildCategory>.value(childCategory)); 
  runApp(ProviderNode(child: MyApp(),providers: providers,));
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Container(
      child:MaterialApp(
        title:'百姓生活+',
        debugShowCheckedModeBanner: false,
        theme: ThemeData(
          primaryColor: Colors.pink
        ),
        home: IndexPage(),
      )
    );
  }
}

 

 

import 'package:flutter/material.dart';
import '../service/service_method.dart';
import 'dart:convert';
import '../model/category.dart';
import 'package:flutter_screenutil/flutter_screenutil.dart';
import 'package:provide/provide.dart';
import '../provide/child_category.dart';

class CategoryPage extends StatefulWidget {
  @override
  _CategoryPageState createState() => _CategoryPageState();
}

class _CategoryPageState extends State<CategoryPage> {
  @override
  Widget build(BuildContext context) {
    //_getCategory();
    return Scaffold(
      appBar: AppBar(title: Text('商品分類'),),
      body: Container(
        child: Row(
          children: <Widget>[
            LeftCategoryNav(),
            Column(
              children: <Widget>[
                RightCategoryNav()
              ],
            )
          ],
        ),
      ),
    );
  }

 
}

//左側大類導航
class LeftCategoryNav extends StatefulWidget {
  @override
  _LeftCategoryNavState createState() => _LeftCategoryNavState();
}

class _LeftCategoryNavState extends State<LeftCategoryNav> {
  List list=[];
  var listIndex=0;
  @override
  void initState() { 
    super.initState();
    _getCategory();//請求接口的數據
  }
  @override
  Widget build(BuildContext context) {
    return Container(
      width: ScreenUtil().setWidth(180),
      decoration: BoxDecoration(
        border: Border(
          right: BorderSide(width:1.0,color: Colors.black12),//有邊框
        )
      ),
      child: ListView.builder(
        itemCount: list.length,
        itemBuilder: (contex,index){
          return _leftInkWell(index);
        },
      ),
    );
  }

  Widget _leftInkWell(int index){
    bool isClick=false;
    isClick=(index==listIndex)?true:false;
    return InkWell(
      onTap: (){
        setState(() {
         listIndex=index; 
        });
        var childList=list[index].bxMallSubDto;//當前大類的子類的列表
        Provide.value<ChildCategory>(context).getChildCategory(childList);
      },
      child: Container(
        height: ScreenUtil().setHeight(100),
        padding: EdgeInsets.only(left:10.0,top:10.0),
        decoration: BoxDecoration(
          color: isClick?Colors.black26: Colors.white,
          border: Border(
            bottom: BorderSide(width: 1.0,color: Colors.black12)
          )
        ),
        child: Text(
          list[index].mallCategoryName,
          style: TextStyle(fontSize: ScreenUtil().setSp(28)),//設置字體大小，爲了兼容使用setSp
        ),
      ),
    );
  }
   void _getCategory() async{
    await request('getCategory').then((val){
      var data=json.decode(val.toString());
      //print(data);
      CategoryModel category= CategoryModel.fromJson(data);
      setState(() {
       list=category.data; 
      });
      //list.data.forEach((item)=>print(item.mallCategoryName));
    });
  }
}

class RightCategoryNav extends StatefulWidget {
  @override
  _RightCategoryNavState createState() => _RightCategoryNavState();
}

class _RightCategoryNavState extends State<RightCategoryNav> {
  //List list = ['名酒','寶丰','北京二鍋頭','捨得','五糧液','茅臺','散白'];
  @override
  Widget build(BuildContext context) {
    return Provide<ChildCategory>(
      builder: (context,child,childCategory){
        return  Container(
          height: ScreenUtil().setHeight(80),
          width: ScreenUtil().setWidth(570),//總的寬度是750 -180
          decoration: BoxDecoration(
            color: Colors.white,//白色背景
            border: Border(
              bottom: BorderSide(width: 1.0,color: Colors.black12)//邊界線
            )
          ),
          child: ListView.builder(
            scrollDirection: Axis.horizontal,
            itemCount: childCategory.childCategoryList.length,
            itemBuilder: (context,index){
              return _rightInkWell(childCategory.childCategoryList[index]);
            },
          ),
        );
      }
    );
  }

  Widget _rightInkWell(BxMallSubDto item){
    return InkWell(
      onTap: (){},//事件留空
      child: Container(//什麼都加一個container，這樣好佈局
        padding: EdgeInsets.fromLTRB(5.0, 10.0, 5.0, 10.0),//上下是10 左右是5.0
        child: Text(
          item.mallSubName,
          style:TextStyle(fontSize: ScreenUtil().setSp(28)),
        ),
      ),
    );
  }
}

category_page.dart