public void ContinueToMain(MainViewModel.SubView? subView = null)
 {
     if (MainViewModel == null) MainViewModel = new MainViewModel();
     if (subView.HasValue)
     {
         switch (subView.Value)
         {
             case MainViewModel.SubView.Auction: if (AuctionViewModel == null) AuctionViewModel = new AuctionViewModelDesign(); break;
             case MainViewModel.SubView.Products: if (ProductsViewModel == null) ProductsViewModel = new ProductsViewModelDesign(); break;
         }
     }
     RunOnUIThread(() => _navigator.NavigateToMainView(subView));
 }
        /* TODO: For each viewmodel, add a public property with a private setter like this:
        public _VIEWNAME_ViewModel _VIEWNAME_ViewModel { get; private set; }
         * Note that the New-View and New-ViewModel commands add the above code automatically (see http://github.com/MacawNL/MvvmQuickCross#new-viewmodel). */

        public void ContinueToMain(MainViewModel.SubView? subView = null, bool skipNavigation = false)
        {
            if (MainViewModel == null) MainViewModel = new MainViewModel();
            if (subView.HasValue)
            {
                switch (subView.Value)
                {
                    case MainViewModel.SubView.Auction: if (AuctionViewModel == null) AuctionViewModel = new AuctionViewModelDesign(); break;
                    case MainViewModel.SubView.Products: if (ProductsViewModel == null) ProductsViewModel = new ProductsViewModelDesign(); break;
                }
            }
            if (!skipNavigation) RunOnUIThread(() => _navigator.NavigateToMainView(CurrentNavigationContext, subView));
        }