Notes on WPF Changes
from February 2006 CTP
to Beta 2

The Beta 2 build of WinFX contains API changes from the February 2006 Community Technology Preview (CTP). While the basic design and principles discussed in Programming Windows Presentation Foundation: Beta Edition are unchanged, some of the details are different from our last list of changes (from November 2005 CTP to February 2006 CDP).

You’ll also want to check out Tim’s “What’s new in Beta 2?” page: http://blogs.msdn.com/tims/archive/2006/05/23/605418.aspx

Layout

• In previous builds, the order in which items appear in a panel can determine both the layout and the Z order. (This is not true of all panels, but it’s true for any panel where the ordering is significant for the layout, e.g. StackPanel, WrapPanel, DockPanel.) Now, it is possible to control the Z order separately using the Panel.ZIndex attached property. This works much like the Z index in earlier UI technologies in Windows

Resources

• References to resources can no longer be forward references. A {StaticResource} or {DynamicResource} must now refer to a resource already defined, whereas before, it could refer to ones defined later in the file.

Interop

• The ElementHost class no longer has multiple children, but instead has a single child. The while the following works in the Feb CTP:

// Feb CTP

host.Control.Add(avButton);

This is what you’ll need to do in beta 2:

// Beta 2

host.Child = avButton;

Also, is seems as if the display isn’t updated ‘til an ElementHost is resized, although I’m not sure why that is just yet.