02-05 flutter provider的使用

class StateManagerByProviderModel with ChangeNotifier{
  int count = 0;
  void increment(){
    count ++;
    notifyListeners();
  }

}

var pmodel = StateManagerByProviderModel();

var providers = Providers();
providers..provide(Provider<StateManagerByProviderModel>.value(pmodel));
runApp(ProviderNode(child: MyApp(), providers: providers));

 @override
  Widget build(BuildContext contuext) {
    return Scaffold(
        appBar: WQAppBar(
            titleName: ""
        ).appBar(context),
        body: Center(
          child: GestureDetector(
            onTap: (){

            },
            child: Provide(
            builder: (context,child,StateManagerByProviderModel scope){
              return Text("${scope.count}");
            }),
//child: Provide<StateManagerByProviderModel>(builder: (context,child,scope){
//              return Text("${scope.count}");
//            }),
          ),
        )
    );
  }

child: GestureDetector(
          onTap: (){
              Provide.value<StateManagerByProviderModel>(context).increment();
              Navigator.of(context).push(CupertinoPageRoute(builder: (context){
                return StateManagerShowPage();
              }));
          },
          child: Text("点击"),
        ),

封装之后

class ThemeConfigInfo {
 Color themeColor = color00CCBB;
}
class ThemeConfigModel extends ThemeConfigInfo with ChangeNotifier{

  Future setThemeColor(themeColor) async{
    this.themeColor = themeColor;
    notifyListeners();
  }
}

class ProvierHelper{

  static var providers = Providers();
  static var themeConfigModel = ThemeConfigModel();

  static init({model,child,dispose = true}){

    providers = Providers()
      ..provide(Provider<ThemeConfigModel>.value(themeConfigModel));

    return ProviderNode(child: child, providers: providers,dispose: dispose);
  }

  static connect<T>({builder, child, scope}) {
    return Provide<T>(builder: builder, child: child, scope: scope);
  }
  static T value<T>(context,{scope}){
    return Provide.value<T>(context,scope: scope);
  }
}

main文件中

runApp(ProvierHelper.init(child: MyApp()));


Widget build(BuildContext context) {
     return  ProvierHelper.connect<ThemeConfigModel>(
      builder: (context,child,ThemeConfigModel model){
       return MaterialApp(
          title: "app",
          localizationsDelegates: [
            // 本地化的代理类
            GlobalMaterialLocalizations.delegate,
            GlobalWidgetsLocalizations.delegate,
            WQCommonLocalizationsDelegate(),
            WQLocalDelegate(),
          ],
          supportedLocales: [
            const Locale('en', 'US'), // 美国英语
            const Locale('zh', 'CN'), // 中文简体
            //其它Locales
          ],
         //这句话是直接设置中文，国际化配置也会失效
         locale: const Locale('zh', 'CN'), // 中文简体

          theme: ThemeData(
            primaryColor:model.themeColor,
            highlightColor: Colors.transparent,
            splashColor: Colors.transparent,
          ),
          routes: WQRoute.routes,
          home: Builder(
            builder: (context){
              return TabbarController();
            },
          ),
        );
      }
    ) ;

改变一个按钮的颜色

Widget build(BuildContext context) {
    return Scaffold(
        body: ListView(
          children: <Widget>[
            ProvierHelper.connect<ThemeConfigModel>(
                builder: (context, child, ThemeConfigModel model) {
                  return RaisedButton(
                    color: model.themeColor,
                    onPressed: () {
                      Navigator.push(context, CupertinoPageRoute(builder: (context) {
                        return SettingPage();
                      }));
                    },
                    child: Text("设置"),

                  );
                })
          ],
        )
    );

改变主题颜色

void changeTheme(){
    ProvierHelper.value<ThemeConfigModel>(context).setThemeColor(colorList[selectedIndex]);
  }