provide状态管理

1、在 pubspec.yaml 中添加依赖

dependencies:

  provide: ^1.0.2

2、编写provide

import 'package:flutter/material.dart';

// with ChangeNotifier必须混入

class Counterwith ChangeNotifier {

intvalue=0;

increment(){

value++;

//    通知监听者  局部刷新widget

    notifyListeners();

}

}

3、在项目的入口文件mian.dart修改

void main() {

var counter =Counter();

var childCategory =ChildCategory();

var providers =Providers();

providers

..provide(Provider.value(counter))

//添加多个时直接.. 

..provide(Provider.value(childCategory));

runApp(ProviderNode(

child:MyApp(),

providers: providers,

));

//  runApp(MyApp());

}

4、需要用到的地方

class _NumberStateextends State {

@override

  Widget build(BuildContext context) {

return Container(

child:Provide<ChildCategory>(

builder: (context,child,counter){

return Text('${counter.value}');

}

)

);

}

}

5、调用里面的方法

class MyButtonextends StatelessWidget {

@override

  Widget build(BuildContext context) {

return Container(

child:RaisedButton(

onPressed: () {

//Provide.value(context).increment();

Provide.value<CategoryGoodsListProvide>(context).getGoodsList(goodsList.data);

},

child:Text("递增"),

),

);

}

}