Add clanker code

dealer/windows/AddOwnerWindow.xaml.cs

@@ -0,0 +1,49 @@
+using System.Windows;
+
+namespace dealer
+{
+    public partial class AddOwnerWindow : Window
+    {
+        private DataManager dataManager;
+
+        /// <summary>
+        /// Gets the owner that was created when the user saved, or null if cancelled.
+        /// </summary>
+        public Owner? CreatedOwner { get; private set; }
+
+        public AddOwnerWindow(DataManager dataManager)
+        {
+            InitializeComponent();
+            this.dataManager = dataManager;
+        }
+
+        private void SaveButton_Click(object sender, RoutedEventArgs e)
+        {
+            if (string.IsNullOrWhiteSpace(JmenoTextBox.Text) && string.IsNullOrWhiteSpace(PrijmeniTextBox.Text))
+            {
+                System.Windows.MessageBox.Show("Vyplnte alespon jmeno nebo prijmeni.", "Upozorneni", MessageBoxButton.OK, MessageBoxImage.Warning);
+                return;
+            }
+
+            var owner = new Owner
+            {
+                Jmeno = JmenoTextBox.Text.Trim(),
+                Prijmeni = PrijmeniTextBox.Text.Trim(),
+                Telefon = TelefonTextBox.Text.Trim(),
+                Email = EmailTextBox.Text.Trim(),
+                Adresa = AdresaTextBox.Text.Trim()
+            };
+
+            dataManager.AddOwner(owner);
+            dataManager.Save();
+            CreatedOwner = owner;
+            this.DialogResult = true;
+            this.Close();
+        }
+
+        private void CancelButton_Click(object sender, RoutedEventArgs e)
+        {
+            this.Close();
+        }
+    }
+}