public void ApplyDocumentChanged()
 {
     try
     {
         if (null != MappingWindowInstance)
         {
             MappingWindowInstance.DozeOff();
             MappingWindowInstance.RefreshLinkInstance();
             MappingWindowInstance.WakeUp();
         }
     }
     catch (Exception ex)
     {
         MessageBox.Show("Failed to apply changes made on the current document.\n" + ex.Message, "Apply Document Changes", MessageBoxButton.OK, MessageBoxImage.Warning);
     }
 }
        public void Execute(UIApplication app)
        {
            try
            {
                CurrentDocument = app.ActiveUIDocument.Document;

                switch (MoverRequest.Take())
                {
                case RequestId.SelectLinkInstance:
                    MainWindowInstance.DozeOff();
                    var picked = PickLinkInstance(out selectedLink);
                    if (picked)
                    {
                        MainWindowInstance.DisplayCategories(selectedLink);
                    }
                    MainWindowInstance.WakeUp();
                    break;

                case RequestId.DuplicateElements:
                    MainWindowInstance.DozeOff();
                    try
                    {
                        selectedLink = ElementMoverUtil.DuplicateSelectedCategories(selectedLink, CurrentDocument, SelectedUpdateMode);
                        if (LinkInstances.ContainsKey(selectedLink.InstanceId))
                        {
                            LinkInstances.Remove(selectedLink.InstanceId);
                        }
                        LinkInstances.Add(selectedLink.InstanceId, selectedLink);
                        MainWindowInstance.UpdateLinkedInstanceProperties();
                    }
                    catch (Exception ex)
                    {
                        var message = ex.Message;
                    }
                    MainWindowInstance.WakeUp();
                    break;

                case RequestId.SelectMappingElements:
                    MappingWindowInstance.DozeOff();
                    Element sourceElement = null;
                    Element targetElement = null;
                    var     pickedMap     = PickMappingElements(out sourceElement, out targetElement);
                    if (pickedMap)
                    {
                        if (LinkInstances.ContainsKey(selectedLink.InstanceId))
                        {
                            LinkInstances.Remove(selectedLink.InstanceId);
                        }
                        LinkInstances.Add(selectedLink.InstanceId, selectedLink);
                        MappingWindowInstance.RefreshLinkInstance();
                    }
                    MappingWindowInstance.WakeUp();
                    break;

                case RequestId.DeleteMappingElements:
                    MappingWindowInstance.DozeOff();
                    if (LinkedElementToDelete.Count > 0)
                    {
                        using (var trans = new Transaction(CurrentDocument))
                        {
                            trans.Start("Delete Element Maps");
                            try
                            {
                                foreach (var linkedInfo in LinkedElementToDelete)
                                {
                                    if (selectedLink.LinkedElements.ContainsKey(linkedInfo.LinkedElementId))
                                    {
                                        selectedLink.LinkedElements.Remove(linkedInfo.LinkedElementId);
                                        var linkedElement = CurrentDocument.GetElement(linkedInfo.LinkedElementId);
                                        if (null != linkedElement)
                                        {
                                            var removed = MoverDataStorageUtil.RemoveLinkedElementInfo(linkedElement);
                                        }
                                    }
                                }
                                trans.Commit();
                                if (LinkInstances.ContainsKey(selectedLink.InstanceId))
                                {
                                    LinkInstances.Remove(selectedLink.InstanceId);
                                    LinkInstances.Add(selectedLink.InstanceId, selectedLink);
                                }
                            }
                            catch (Exception ex)
                            {
                                trans.RollBack();
                                MessageBox.Show("Failed to delete element maps.\n" + ex.Message, "Delete Element Maps", MessageBoxButton.OK, MessageBoxImage.Warning);
                            }
                        }
                        MappingWindowInstance.RefreshLinkInstance();
                    }
                    MappingWindowInstance.WakeUp();
                    break;

                case RequestId.ShowElement:
                    MappingWindowInstance.DozeOff();
                    if (null != SelectedLinkedInfo)
                    {
                        if (null != CurrentDocument.GetElement(SelectedLinkedInfo.LinkedElementId))
                        {
                            HighlightElement();
                        }
                    }
                    MappingWindowInstance.WakeUp();
                    break;

                case RequestId.AddFamilyMapping:
                    FamilyWindowInstance.DozeOff();
                    if (null != SelectedFamilyInfo)
                    {
                        var tType = CurrentDocument.GetElement(SelectedFamilyInfo.TargetTypeId) as ElementType;
                        if (null != tType)
                        {
                            using (var trans = new Transaction(CurrentDocument))
                            {
                                trans.Start("Add Family Map");
                                try
                                {
                                    if (selectedLink.LinkedFamilies.ContainsKey(SelectedFamilyInfo.TargetTypeId))
                                    {
                                        selectedLink.LinkedFamilies.Remove(SelectedFamilyInfo.TargetTypeId);
                                    }
                                    selectedLink.LinkedFamilies.Add(SelectedFamilyInfo.TargetTypeId, SelectedFamilyInfo);

                                    var updated = MoverDataStorageUtil.UpdateLinkedFamilyInfo(SelectedFamilyInfo, tType);

                                    if (LinkInstances.ContainsKey(selectedLink.InstanceId))
                                    {
                                        LinkInstances.Remove(selectedLink.InstanceId);
                                        LinkInstances.Add(selectedLink.InstanceId, selectedLink);
                                    }
                                    trans.Commit();
                                    MappingWindowInstance.RefreshLinkInstance();
                                }
                                catch (Exception ex)
                                {
                                    trans.RollBack();
                                    var message = ex.Message;
                                }
                            }
                        }
                    }

                    FamilyWindowInstance.WakeUp();
                    break;

                case RequestId.DeleteFamilyMapping:
                    MappingWindowInstance.DozeOff();
                    if (null != SelectedFamilyInfo)
                    {
                        using (var trans = new Transaction(CurrentDocument))
                        {
                            trans.Start("Delete Family Map");
                            try
                            {
                                foreach (var familyInfo in LinkedFamilyToDelete)
                                {
                                    if (selectedLink.LinkedFamilies.ContainsKey(familyInfo.TargetTypeId))
                                    {
                                        selectedLink.LinkedFamilies.Remove(familyInfo.TargetTypeId);
                                        var tType = CurrentDocument.GetElement(familyInfo.TargetTypeId) as ElementType;
                                        if (null != tType)
                                        {
                                            var removed = MoverDataStorageUtil.RemoveLinkedFamilyInfo(tType);
                                        }
                                    }
                                }
                                trans.Commit();
                                if (LinkInstances.ContainsKey(selectedLink.InstanceId))
                                {
                                    LinkInstances.Remove(selectedLink.InstanceId);
                                    LinkInstances.Add(selectedLink.InstanceId, selectedLink);
                                }
                                MappingWindowInstance.RefreshLinkInstance();
                            }
                            catch (Exception ex)
                            {
                                trans.RollBack();
                                var message = ex.Message;
                            }
                        }
                    }
                    MappingWindowInstance.WakeUp();
                    break;

                case RequestId.None:
                    return;
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show("Failed to execute external event handler.\n" + ex.Message, "Execute External Event Handler", MessageBoxButton.OK, MessageBoxImage.Warning);
            }
        }