How can I change state using provider package

Question

I have a simple app to practice provider package to change state, when the user logs in at initState I change the visibility of the splash screen to false, Thus loading my main app

@override
  void initState() {
    super.initState();
     setState(() {
      splash = false;
      floatingActionButton = true;
    });
}

//this is the position widget that becomes invisible. I.e the splash screen is offloaded

 @override
  Widget build(BuildContext context) {
  Positioned(
              top: 0,
              left: 0,
              right: 0,
              child: Visibility(
                visible: splash,
                maintainState: false,
                maintainAnimation: false,
                maintainSize: false,
                maintainInteractivity: false,
                child: Container(
                  decoration: BoxDecoration(
                    gradient: LinearGradient(
                        begin: Alignment.topRight,
                        end: Alignment.bottomLeft,
                        colors: [
                          Color(0xFFFF800B),
                          Color(0xFFCE1010),
                        ]),
                  ),
                  // color: Colors.white,
                 
              ),
            )

Now, I want to do the same thing with provider package Here is the class for it

class AppData extends ChangeNotifier {
 bool splashMainScreen;
  bool floatActBtnMainScreen;
 void closeSplashScreen(bool splash, bool floatActBtn) {
    splashMainScreen = splash;
    floatActBtnMainScreen = floatActBtn;
    notifyListeners();
  }
}

From hereon I don't know how to pass the state to the AppData class and back to the widget The least I could do was something like this

@override
  void initState() {
    super.initState();
     
 Provider.of<AppData>(context, listen: false)
        .closeSplashScreen(false, false);

I want to change visible: splash to false with the provider package instead of setState, Any help ? as I keep getting the error 'package:flutter/src/widgets/visibility.dart': Failed assertion: line 67 pos 15: 'visible != null': is not true. package:flutter/…/widgets/visibility.dart:1

 Positioned(
              top: 0,
              left: 0,
              right: 0,
              child: Consumer<AppData>(
                builder: (ctx, dsc, child) => Visibility(
                  visible: dsc.splashMainScreen,
                  maintainState: false,
                  maintainAnimation: false,
                  maintainSize: false,
                  maintainInteractivity: false,
                  child: Container(
                    decoration: BoxDecoration(
                      gradient: LinearGradient(
                          begin: Alignment.topRight,
                          end: Alignment.bottomLeft,
                          colors: [
                            Color(0xFFFF800B),
                            Color(0xFFCE1010),
                          ]),
                    ),

Answer 1

I don't know if I understand question well, but try this:

first create provider file :

class AppData extends ChangeNotifier {
  bool splash = false;
  bool floatingActionButton = true;
  void closeSplashScreen() {
    splash = true;
    floatingActionButton = false;
    notifyListeners();
  }
}

Now use the initial values using consumer :

@override
  Widget build(BuildContext context) {
  Positioned(
              top: 0,
              left: 0,
              right: 0,
              child:Consumer<AppData>(builder:(context,appData,child){
              return  Visibility(
                visible: appData.splash,
                maintainState: false,
                maintainAnimation: false,
                maintainSize: false,
                maintainInteractivity: false,
                child: Container(
                  decoration: BoxDecoration(
                    gradient: LinearGradient(
                        begin: Alignment.topRight,
                        end: Alignment.bottomLeft,
                        colors: [
                          Color(0xFFFF800B),
                          Color(0xFFCE1010),
                        ]),
                  ), 
              ),
            ));
})

now you can change the values of splash and floatingActionButton using closeSplashScreen() in provider such us this :

Consumer<AppData>(builder:(context,appData,child){
    return ElevatedButton(
       onPresse : appData.closeSplashScreen();
       child:Text('change')
    );
}

then don't use statefull widget

Hope this works