private static void AddRoomButton_Click(object sender, RoutedEventArgs e) { Button addRoomButton = (Button)sender; List <object> objects = (List <object>)addRoomButton.Tag; ComboBox hotelComboBox = (ComboBox)objects[0]; TextBox roomNumberTextBox = (TextBox)objects[1]; ComboBox roomTypeComboBox = (ComboBox)objects[2]; Button browseRoomPhotoButton = (Button)objects[3]; Window popup = (Window)objects[4]; DataModels database = DataModels.GetInstance(); if (hotelComboBox.SelectedItem == null) { MessageBox.Show("Please select a hotel"); return; } Hotel hotel = (Hotel)((ComboBoxItem)hotelComboBox.SelectedItem).Content; int roomNumber; if (!int.TryParse(roomNumberTextBox.Text, out roomNumber)) { MessageBox.Show("Please enter a valid room number"); return; } if (roomTypeComboBox.SelectedItem == null) { MessageBox.Show("Please select a room type"); return; } RoomType roomType = (RoomType)((ComboBoxItem)roomTypeComboBox.SelectedItem).Content; if ((string)browseRoomPhotoButton.Tag == "") { MessageBox.Show("Please select a photo path"); return; } CustomImage roomImage = new CustomImage((string)browseRoomPhotoButton.Tag); Room room = new Room(roomNumber, hotel, roomType, roomImage, new List <RoomView>()); if (database.AddRoom(room) == true) { MessageBox.Show("Added"); if (adminWindow.currentCanvas != null) { adminWindow.currentCanvas.Hide(); } adminWindow.InitializeRoomsCanvas(database.GetAllRooms()); popup.Close(); return; } else { MessageBox.Show("please enter a valid room number"); return; } }