The difference between using the Flutter state management and provide the provider of

He said state management have to say Google personally developed two state management Widget : the first one is provide the second one is provider .

This difference is a two out early, it did not seem a whole it updated. The second is the 2019 version came out only now is provider: ^3.2.0 . On a stay in provide: ^1.0.2 , basically the GG. But sometimes you might need for the project provide . So now I want to say is that these two basic usage, or is the contrast between the two use of it (state control multiple interfaces, the project may be more states to manage multiple interfaces.

Provide with the project previously encountered a problem later changed Provider, build reconstruction. provide will not rebuild, provider will be rebuilt.

To solve the problem: you can choose not to listen  the listen : false or change to initstate.

First, create

1, create aprovide，还用上次例子的counter

Import ' Package: Flutter / material.dart ' ; 

class Counter with ChangeNotifier { 
   int value = 0 ; 

  INCREMENT () { 
    value ++ ; 
    notifyListeners (); // change notification listener 
  } 

}

2, create aprovider

import 'package:flutter/material.dart';

class Counter with ChangeNotifier {
  int _count = 0;
  get count => _count;

  void increment() {
    _count++;
    notifyListeners(); //通知
  }
  
}

Second, top-dependent

1、provide

void main() {
  //顶层依赖
var counter = Counter();
var providers = Provider();
  providers
    ..(Provider<Counter>.value(counter));
  runApp(ProviderNode(child: MyApp(), providers: providers));
}

2、provider

void main() { 

  runApp(
    MultiProvider(
      providers: [
        ChangeNotifierProvider.value(value: Counter()),
        //ChangeNotifierProvider(builder: (_) => Counter()),        
      ],
      child: MyApp(),
    ),
  );

}

Third, the use

1、provide

Provide.value <Counter> (context) .increment ();
 // with the increment off method. . Here you can also pass parameters into account simply write the Counter inside the increment which accepts two parameters like

2、provider

Provider.of <Counter> (context, the listen: to false ) .increment (); // here may also pass parameters

Fourth, get the value

1、provide

return Provide<ZxxxDetailsProvide>(
   builder: (context,child,val){
      var goodsInfo = Provide.value<ZxxxDetailsProvide>(context).goodsInfo.data;
   }
);

2、provider

return Consumer<ZxxxListProvide>(
    builder: (context,model,child){
        ...
    }
);

Important: use  providerthe time we have to pay attention to a certain set listen to the Bool value is such

await Provider.of<DetailsInfoProvide>(context, listen: false).getGoodsInfo(goodsId);