public void SwitchScreen(object sender)
        {
            var screen = ((UserControl)sender);

            if (screen != null)
            {
                StackPanelMain.Children.Clear();
                StackPanelMain.Children.Add(screen);

                if (screen.Name == "EditClinic")
                {
                    AddAdministratorView administratorsView = new AddAdministratorView();
                }
                else if (screen.Name == "Maintenances")
                {
                    MaintenancesView maintenancesView = new MaintenancesView();
                }
                else if (screen.Name == "Managers")
                {
                    ManagersView managersView = new ManagersView();
                }
                else if (screen.Name == "Doctors")
                {
                    DoctorsView doctorsView = new DoctorsView();
                }
                else if (screen.Name == "Patients")
                {
                    PatientsView patientsView = new PatientsView();
                }
            }
        }
        public void SwitchScreen(object sender)
        {
            var screen = ((UserControl)sender);

            if (screen != null)
            {
                StackPanelMain.Children.Clear();
                StackPanelMain.Children.Add(screen);

                if (screen.Name == "Doctors")
                {
                    DoctorsView doctorsView = new DoctorsView();
                }
            }
        }