Catel.Windows.WindowExtensions.SetOwnerWindow C# (CSharp) Method

        private static void SetOwnerWindow(SystemWindow window, SystemWindow ownerWindow, IntPtr ownerHandle, bool forceNewOwner, bool focusFirstControl)
        {
            if (focusFirstControl)
            {
                window.FocusFirstControl();
            }

            if (!forceNewOwner && HasOwner(window))
            {
                return;
            }

            try
            {
                if (ownerWindow != null)
                {
                    if (ReferenceEquals(ownerWindow, window))
                    {
                        Log.Warning("Cannot set owner window to itself, no owner window set");
                        return;
                    }

                    if (window.Dispatcher.GetThreadId() != ownerWindow.Dispatcher.GetThreadId())
                    {
                        Log.Warning("The owner window '{0}' is not created on the same thread as the current window '{1}', cannot set owner window",
                            ownerWindow.GetType().GetSafeFullName(false), window.GetType().GetSafeFullName(false));
                        return;
                    }

                    window.Owner = ownerWindow;
                }
                else
                {
                    // Set owner via interop helper
                    var interopHelper = new WindowInteropHelper(window);
                    interopHelper.Owner = ownerHandle;

                    // Get handler (so we can nicely unsubscribe)
                    RoutedEventHandler onWindowLoaded = null;
                    onWindowLoaded = delegate(object sender, RoutedEventArgs e)
                    {
                        // Since this owner type doesn't support WindowStartupLocation.CenterOwner, do
                        // it manually
                        if (window.WindowStartupLocation == WindowStartupLocation.CenterOwner)
                        {
                            // Get the parent window rect
                            RECT ownerRect;
                            if (GetWindowRect(ownerHandle, out ownerRect))
                            {
                                // Get some additional information
                                int ownerWidth = ownerRect.Right - ownerRect.Left;
                                int ownerHeight = ownerRect.Bottom - ownerRect.Top;
                                int ownerHorizontalCenter = (ownerWidth / 2) + ownerRect.Left;
                                int ownerVerticalCenter = (ownerHeight / 2) + ownerRect.Top;

                                // Set the location to manual
                                window.WindowStartupLocation = WindowStartupLocation.Manual;

                                // Now we know the location of the parent, center the window
                                window.Left = ownerHorizontalCenter - (window.ActualWidth / 2);
                                window.Top = ownerVerticalCenter - (window.ActualHeight / 2);
                            }
                        }

                        ((SystemWindow)sender).Loaded -= onWindowLoaded;
                    };

                    window.Loaded += onWindowLoaded;
                }
            }
            catch (Exception ex)
            {
                Log.Error(ex, "Failed to set the owner window");
            }
        }