DashboardViewModel.cs

public class DashboardViewModel : ViewModelBase
{
    IDbService _dbService;
    INavigationService _navigationService;
    IMonthService _monthService;

    public DashboardViewModel(IDbService dbService, INavigationService navigationService, IMonthService monthService)
    {
        _dbService = dbService;
        _navigationService = navigationService;
        _monthService = monthService;
    }
}