Provider

There are two providers used in the app. The UserDataProvider() and the ThemeProvider().

They are setup globally in the main.dart file with a MultiProvider()

MultiProvider(
  providers: [
    ChangeNotifierProvider(
      create: (context) {
        return UserDataProvider();
      },
    ),
    ChangeNotifierProvider(
      create: (context) {
        return ThemeProvider();
      },
    ),
  ],
  ...

UserDataProvider()

The UserDataProvider() is updated whenever the database listener registers an update in the userdata. This logic is implemented in the UserDataWrapper(). Whenever the is a part of the UI that must update when the user data changes in the database, the user data can be read from the provider:

context.listen<UserDataProvider>().userData

ThemeProvider()

The ThemeProvider() contains no data but is only used as notification whenever something in the Theme or UI updates and the whole up needs to rebuild. E.g. in the SwithLightDarkTheme1()

context.read<ThemeProvider>().notify();

To rebuild the app the top level MaterialApp() widget in main.dart is wrapped with a ChangeNotifierProvider() that has the ThemeProvider as a consumer.

ChangeNotifierProvider(
    create: (context) => ThemeProvider(),
    child: Consumer<ThemeProvider>(
        builder: (context, themeProvider, child) {
        ...