.

views/MainWindow.xaml.cs

@@ -25,7 +25,8 @@ namespace DeviceCenter
             devices.Add(new AcsDevice() { name = "Device 3", ip = "192.168.1.12", status = Device.Status.CONNECTED });
 
             lv_device.ItemsSource = devices;
-            Thread t = new Thread(()=> {
+            Thread t = new Thread(() =>
+            {
                 Thread.Sleep(2000);
                 devices[0].status = Device.Status.CONNECTED;
             });
@@ -40,7 +41,10 @@ namespace DeviceCenter
         private void btn_add_device_Click(object sender, RoutedEventArgs e)
         {
             AddDevice addDevice = new AddDevice();
-            addDevice.ShowDialog();
+            if (addDevice.ShowDialog() ?? false)
+            {
+                
+            }
         }
 
         private void btn_del_device_Click(object sender, RoutedEventArgs e)