protected override void OnDrop(DragEventArgs e)
{
ModelTreeManager manager = this.Context.Services.GetService <ModelTreeManager>();
// When dragging from toolbox:
// editingScope should not be null
// there should only be one item
// When dragging from canvas:
// editingScope should be null
// Call editingScope.Complete() to commit changes, otherwise the editing scope will be aborted
using (EditingScope editingScope = ModelItemHelper.TryCreateImmediateEditingScope(manager, SR.PropertyChangeEditingScopeDescription))
{
List <object> droppedObjects = this.GetSortedObjectList(e);
#pragma warning disable 618
DragDropHelper.SetDragDropCompletedEffects(e, DragDropEffects.None);
#pragma warning restore 618
if (droppedObjects == null || droppedObjects.Count == 0)
{
return;
}
if (droppedObjects.Count == 1)
{
if (this.DoSingleDrop(droppedObjects[0], e))
{
if (editingScope != null)
{
editingScope.Complete();
}
}
return;
}
else
{
// multi drop
Fx.Assert(editingScope == null, "editingScope should be null for dragging from canvas.");
this.DoAutoWrapDrop(InsertionPosition.None, e, droppedObjects);
}
base.OnDrop(e);
}
}
bool DoAutoWrapDrop(InsertionPosition insertionPos, DragEventArgs e, IList <object> droppedObjects = null)
{
if (droppedObjects == null)
{
ModelTreeManager manager = this.Context.Services.GetRequiredService <ModelTreeManager>();
EditingScope editingScope = null;
try
{
editingScope = ModelItemHelper.TryCreateImmediateEditingScope(manager, SR.WrapInSequenceDescription);
droppedObjects = this.GetSortedObjectList(e);
if (!this.DoAutoWrapDrop(insertionPos, droppedObjects))
{
return(false);
}
if (editingScope != null)
{
editingScope.Complete();
}
}
finally
{
if (editingScope != null)
{
editingScope.Dispose();
editingScope = null;
}
}
}
else
{
if (!this.DoAutoWrapDrop(insertionPos, droppedObjects))
{
return(false);
}
}
if (!DragDropHelper.IsDraggingFromToolbox(e))
{
List <WorkflowViewElement> movedViewElements = ObjectList2WorkflowViewElementList(droppedObjects);
DragDropHelper.SetDragDropMovedViewElements(e, movedViewElements);
//Backward compatibility for 4.0
if (droppedObjects.Count == 1 && movedViewElements.Count == 1)
{
#pragma warning disable 618
DragDropHelper.SetDragDropCompletedEffects(e, DragDropEffects.Move);
#pragma warning restore 618
}
}
else
{
Fx.Assert(droppedObjects.Count == 1, "Dropping from Toolbox with count != 1");
// Set focus if it is dropping from ToolBox.
// In common drag/drop, the selection setting is done at the end of
// StartDragging().
if (this.Item == null)
{
return(true);
}
Fx.Assert(typeof(Sequence).IsAssignableFrom(this.Item.ItemType),
"Auto Wrap didn't add a sequence. Is Item.Properties[\"Activities\"] still correct?");
foreach (ModelItem item in this.Item.Properties["Activities"].Collection)
{
// Find the ModelItem whose value is an activity from Toolbox.
if (item.GetCurrentValue() == droppedObjects[0])
{
this.Dispatcher.BeginInvoke(DispatcherPriority.ApplicationIdle, (Action)(() =>
{
item.Focus();
}));
break;
}
}
}
return(true);
}