public static DeckTraversalMessage ForDeckTraversal(DeckTraversalModel traversal)
{
DeckTraversalMessage message;
if (traversal is SlideDeckTraversalModel)
{
message = new SlideDeckTraversalMessage((SlideDeckTraversalModel)traversal);
}
else if (traversal == null)
{
throw new ArgumentNullException("traversal");
}
else
{
throw new ArgumentException("Unknown deck traversal type: " + traversal.ToString());
}
// Set the message's predecessor to the current TableOfContents.Entry.
using (Synchronizer.Lock(traversal.SyncRoot)) {
if (traversal.Current != null)
{
Message predecessor = message.Predecessor;
message.Predecessor = new SlideInformationMessage(traversal.Current.Slide);
message.Predecessor.InsertChild(new TableOfContentsEntryMessage(traversal.Current));
message.Predecessor.AddOldestPredecessor(predecessor);
}
return(message);
}
}
/// <summary>
/// We receive this message when an instructor navigates between slides in a deck. There's also one that we
/// want to ignore that occurs when the instructor opens a new deck but before navigating to a slide in the deck.
/// </summary>
/// <param name="stdm"></param>
/// <returns></returns>
internal object AddSlideDeckTraversal(CP3Msgs.SlideDeckTraversalMessage stdm)
{
//If m.Predecessor.Child is a TOC entry, look up info for RTUPdate there.
if ((stdm.Predecessor != null) && (stdm.Predecessor.Child != null) &&
(stdm.Predecessor is CP3Msgs.SlideInformationMessage) &&
(stdm.Predecessor.Child is CP3Msgs.TableOfContentsEntryMessage) &&
(stdm.Parent != null) && (stdm.Parent is CP3Msgs.DeckInformationMessage))
{
//Debug.WriteLine(stdm.Parent.Parent.ToString(), "*****");
//We get one of these when a deck is first opened, but before the instructor navigates to it. Filter it out
//by remembering the current deck ID and ignoring messages for decks other than the current.
if ((currentDeckId == Guid.Empty) || (currentDeckId.Equals((Guid)stdm.Parent.TargetId)))
{
currentSlideId = (Guid)stdm.Predecessor.TargetId;
currentDeckId = (Guid)stdm.Parent.TargetId;
RTUpdate rtu = this.toc.GetRtUpdate((Guid)stdm.Predecessor.Child.TargetId);
return(rtu);
}
}
else
{
//No warning because this happens when a new SS deck is created upon receipt of the first submission.
Debug.WriteLine("A SlideDeckTraversal is being ignored because it lacks the expected message graph.");
}
return(null);
}
public static DeckTraversalMessage ForDeckTraversal(DeckTraversalModel traversal)
{
DeckTraversalMessage message;
if(traversal is SlideDeckTraversalModel)
message = new SlideDeckTraversalMessage((SlideDeckTraversalModel) traversal);
else if(traversal == null)
throw new ArgumentNullException("traversal");
else
throw new ArgumentException("Unknown deck traversal type: " + traversal.ToString());
// Set the message's predecessor to the current TableOfContents.Entry.
using(Synchronizer.Lock(traversal.SyncRoot)) {
if( traversal.Current != null ) {
Message predecessor = message.Predecessor;
message.Predecessor = new SlideInformationMessage( traversal.Current.Slide );
message.Predecessor.InsertChild( new TableOfContentsEntryMessage( traversal.Current ) );
message.Predecessor.AddOldestPredecessor( predecessor );
}
return message;
}
}
