The Control Local Values Bug Solution and new WPF 4.0 related APIs

Vincent Sibal's Blog : The Control Local Values Bug!

Vincent Sibal's Blog : The Control Local Values Bug! — Thu, 21 May 2009 18:20:46 GMT

PingBack from http://blogs.msdn.com/vinsibal/archive/2009/03/24/the-control-local-values-bug.aspx

re: The Control Local Values Bug Solution and new WPF 4.0 related APIs

PaulF — Sat, 06 Jun 2009 05:30:16 GMT

Please don't confuse lack of comments with lack of interest in what you are posting.

That is a pretty easy thing to do.

This is one of my favorite msdn blogs, but...., I don't really have anything to add to what you said in this post or others aside from please keep it up.

Great work keeping all of us developers informed on what is going on at Microsoft.

Also, I am very happy to see Microsoft fixing issues like this.

re: The Control Local Values Bug Solution and new WPF 4.0 related APIs

vinsibal — Sat, 06 Jun 2009 17:25:03 GMT

Thanks a lot Paul!

interest

Rune — Fri, 12 Jun 2009 16:02:17 GMT

I just discovered this blog. I've bookmarked it for future refernce and I agree with what Paul said.

(I came here because I'm trying to discover how to enable deferred scrolling in the datagrid)

re: The Control Local Values Bug Solution and new WPF 4.0 related APIs

vinsibal — Fri, 12 Jun 2009 18:39:07 GMT

Rune,

See this post, http://blogs.msdn.com/vinsibal/archive/2008/05/22/wpf-3-5-sp1-feature-non-live-scrolling.aspx.

re: The Control Local Values Bug Solution and new WPF 4.0 related APIs

Fahad — Fri, 12 Jun 2009 23:41:23 GMT

This only solves if we use .NET 4.0 beta (or future versions), but how do we solve it in .NET 3.5 FW, this seems to be rather trivial that I do not wish to upgrade to VS2010 yet, then how do i do it? Do we simply reset the BindingExpression?

var be = tb.GetBindingExpression(TextBox.TextProperty);

// make my changes in internally

// reset the BindingExpression

tb.SetBinding(TextBox.TextProperty, be)

I just thought of this idea, What do you think about it?

re: The Control Local Values Bug Solution and new WPF 4.0 related APIs

vinsibal — Sat, 13 Jun 2009 01:24:49 GMT

Fahad,

The solution you propose make work for a simple problem but it does not scale for many of the common scenarios. Take the DatePicker example that I talk about in the previous blog post, http://blogs.msdn.com/vinsibal/archive/2009/03/24/the-control-local-values-bug.aspx. In OnIsDropDownChanged a member, _popUp.IsOpen is set to a local value. How would you undo that? From the outside you need to get access to _popUp which may or may not be possible and you need to know the kind of expression and ValueSource on IsOpen prior to it being set to a local value. If you knew exactly where this would happen in code and had access to everything then it may work. Since you don't have access to a lot of the Control specific implementation, it makes it impossible to work around this issue. So unfortunately, there is not work around this issue in pre 4.0 bits.

re: The Control Local Values Bug Solution and new WPF 4.0 related APIs

Fahad — Sat, 13 Jun 2009 19:49:21 GMT

Thanks for your views Vincent, I agree with your point!!!