private void ResetUserInterface()
 {
     if (activeBooking != null)
     {
         bookings.DeleteID(activeBooking.GetID());
         activeBooking = null;
         screen.ClearTextBoxes();
         screen.DisableButtons();
     }
 }
        public void BookingCollectionDeleteIDSuccess()
        {
            BookingCollection testCollection = new BookingCollection();

            Date   mockDate   = Substitute.For <Date>(12, 9, 2019);
            Time   mockTime   = Substitute.For <Time>(12, 54);
            IVenue mockVenue  = Substitute.For <IVenue>();
            Client mockClient = Substitute.For <Client>("123", "CompanyName1", "CompanyAddress1");

            Booking booking1 = new Booking("1", BookingType.FACILITATED,
                                           mockClient, mockDate, mockTime, mockVenue);
            Booking booking2 = new Booking("2", BookingType.FACILITATED,
                                           mockClient, mockDate, mockTime, mockVenue);

            testCollection.Add(booking1);
            testCollection.Add(booking2);

            testCollection.DeleteID("1");

            Assert.AreEqual <int>(1, testCollection.GetSize());
            Assert.IsTrue(testCollection.Contains(booking2));
        }