presence_new/Presence.Desktop/ViewModels/MainWindowViewModel.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using domain.UseCase;
using Microsoft.Extensions.DependencyInjection;
using presence.data.RemoteData.RemoteDataBase;
using presence.domain.UseCase;
using ReactiveUI;

namespace Presence.Desktop.ViewModels
{
    public class MainWindowViewModel: ViewModelBase, IScreen
    {
        public RoutingState Router { get; } = new RoutingState();

        public MainWindowViewModel(IServiceProvider serviceProvider)
        {
            var iGroupUseCase = serviceProvider.GetRequiredService<IGroupUseCase>();
            var presenceUseCase = serviceProvider.GetRequiredService<PresenceUseCase>();
            
            Router.Navigate.Execute(new GroupViewModel(iGroupUseCase, presenceUseCase, this));
        }
    }
}