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Two weeks ago, I spent an entire week at a customer site. This customer is in Raleigh, NC, and I got to see their early progress on a WPF prototype. They see the User Experience opportunities with WPF as a key differentiator in their market.

This opportunity came about because of a program that the Server and Tools Business within Microsoft runs, called Frontline. This program is why I spent the week with our Customer Support organization in April in Texas.

We always try to look for win win situations. In the Frontline case, I think that this program is a true win-win.

Pablo is one the most senior people on the WPF team and has been a key decision maker in deciding what scenarios WPF would address.

 

http://www.fernicola.org/loquitor/index.php?/archives/19-When-to-use-WPF-and-when-to-use-other-technologies.html

I'm going to call out one point in particular, because I see a lot of people, including internally confused about WPF 3D. 

if you already have domain knowledge in Direct3D (or OpenGL), you should stick with using Direct3D for WPF v1.

Now, to provide more context on my guidance.

I was going to post something about the various levels you can use in WPF for graphics, but Pablo Fernicola beat me to it:  http://www.fernicola.org/loquitor/index.php?/archives/17-WPF-Pick-Your-API-Abstraction.html

CollectionView is a very interesting construct.  After including it in my ViewModel I meant to quickly blog about the usage...but when I started thinking about it and reading a bit more about it, it becomes even more interesting.  Lots of good blogging.  However, while I think about it, let me quickly make my original point.

The Model has a simple List.  CollectionView wraps a Collection and adds concepts like selection, sorting and filtering to it and supports the INotify... goodness that data binding wants in order to do a really good job.

Rob Relyea from the Avalon team has a cool intro to 'attached properties', but sadly he doesn't go into the real fun you can have with attached properties. Basically they let you store data on arbitrary DependencyObjects, but the key is that they provide a callback whenever that data changes. Suddenly, this sealed to the hilt behemoth of an API can be extended.

My current side project is to create my own set of extensible events and actions, but since EventTrigger and TriggerAction are sealed and give us non-Avalon folks no love, enter attached properties:

<Rectangle Name='RedRect' Width='100' Height='66.6' Fill='Red'>
   <evt:Triggers.Triggers>
       <evt:PropertyTrigger Trigger='{Binding ElementName=RedRect, Path=IsMouseOver}' Value='True'>
           <evt:SetterAction Property='IsActive' Value='True' Target='{Binding}'/>
           <evt:MethodAction Method='Play' Target='{Binding ElementName=VideoFrame}'/>
       evt:PropertyTrigger>
   evt:Triggers.Triggers>
Rectangle>

So Triggers.Triggers is an attached property of a collection of Trigger objects.