Xamarin.Forms + PrismでViewModelの名称をViewModelとして名前解決する場合の設定

App.xaml.cs

using System;
using System.Reflection;
using Prism.Unity;
using Alermer.Views;
using Prism.Mvvm;
using Xamarin.Forms;

namespace Alermer
{
    public partial class App : PrismApplication
    {
        public App(IPlatformInitializer initializer = null) : base(initializer) { }

        protected override void OnInitialized()
        {
            InitializeComponent();

            NavigationService.NavigateAsync("NavigationPage/MainPage?title=Hello%20from%20Xamarin.Forms");
        }

        protected override void RegisterTypes()
        {
            Container.RegisterTypeForNavigation<NavigationPage>();
            Container.RegisterTypeForNavigation<MainPage>();
        }

        protected override void ConfigureViewModelLocator()
        {
            base.ConfigureViewModelLocator();
            ViewModelLocationProvider.SetDefaultViewTypeToViewModelTypeResolver(
                viewType =>
                {
                    var viewName = viewType.FullName;
                    viewName = viewName.Replace(".Views.", ".ViewModels.");
                    string viewModelName;
                    if (viewName.EndsWith("Page"))
                    {
                        viewModelName =
                            $"{viewName.Substring(0, viewName.LastIndexOf("Page", StringComparison.Ordinal))}ViewModel";
                    }
                    else
                    {
                        var suffix = viewName.EndsWith("View") ? "Model" : "ViewModel";
                        viewModelName = $"{viewName}{suffix}";
                    }

                    var viewAssemblyName = viewType.GetTypeInfo().Assembly.FullName;
                    return Type.GetType($"{viewModelName}, {viewAssemblyName}");
                });
        }
    }
}