changeAppThemeMode method
Implementation
changeAppThemeMode(FTxAppThemeType? themeType) async {
FTxAppTheme.defaultThemeType = themeType!;
SharedPreferences sharedPreferences = await SharedPreferences.getInstance();
await sharedPreferences.setInt("fx_app_theme_mode", themeType.index);
log(FTxAppTheme.getThemeFromThemeMode().toString());
notifyListeners();
}