ChatterBox.Client.Presentation.Shared.ViewModels.MainViewModel.MainViewModel C# (CSharp) Method

        public MainViewModel(
            WelcomeViewModel welcomeViewModel,
            ConnectingViewModel connectingViewModel,
            ContactsViewModel contactsViewModel,
            SettingsViewModel settingsViewModel,
            CoreDispatcher uiDispatcher) : base(uiDispatcher)
        {
            WelcomeViewModel = welcomeViewModel;
            ConnectingViewModel = connectingViewModel;
            ContactsViewModel = contactsViewModel;
            SettingsViewModel = settingsViewModel;

            WelcomeViewModel.OnCompleted += WelcomeCompleted;
            ConnectingViewModel.OnRegistered += ConnectingViewModel_OnRegistered;
            ConnectingViewModel.OnRegistrationFailed += ConnectingViewModel_OnRegistrationFailed;
            ShowSettingsCommand = new DelegateCommand(() => IsSettingsVisible = true);

            WelcomeViewModel.OnShowSettings += () => IsSettingsVisible = true;
            ContactsViewModel.OnShowSettings += () => IsSettingsVisible = true;
            ConnectingViewModel.OnShowSettings += () => IsSettingsVisible = true;
            SettingsViewModel.OnClose += SettingsViewModelOnClose;
            SettingsViewModel.OnRegistrationSettingsChanged += RegistrationSettingChanged;
        }