Databinding in Windows Store apps to an ExpandoObject: Change notification not working - by LukePuplett

Status : 

  External<br /><br />
		This item may be valid but belongs to an external system out of the direct control of this product team.<br /><br />
		A more detailed explanation for the resolution of this particular item may have been provided in the comments section.

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ID 836252 Comments
Status Closed Workarounds
Type Bug Repros 0
Opened 3/18/2014 10:48:12 AM
Access Restriction Public


Note: This bug is raised to the VS tooling/CLR team though I understand that Windows Store issues are owned by the Windows team. Until the Windows team has a connect of its own, I'm filing issues here.

In WPF you can use an ExpandoObject as a view model. In Windows Store apps, you can do the same and the initial values are read into the UI controls, but subsequent changes are not reflected in the UI.

Although ExpandoObject implements INotifyPropertyChanged, the binding system seems to fail somewhere on updates.

My tests show that the ExpandoObject raises the event properly.

A less obvious, cool thing about using ExpandoObject is that it allows code-behind to write to the DataContext using code such as:

((dynamic)this.DataContext).Property = value;

Which compiles and works for both ExpandoObject-based view models and view model classes without having to perform manual type checking and casting.
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Posted by asdfasf on 5/6/2014 at 6:56 AM
I am also having this problem. What is the status of this bug? It would be bad to have to abandon ExpandoObject in Windows Store App.
Posted by Microsoft on 3/25/2014 at 1:31 AM
Thank you for your bug submission. The issue you reported appears to be on a released Windows Product. If this issue is severe, causing critical business situations or blocking your product development or deployment, please go to or call 1-800-MICROSOFT for assistance. For Microsoft premier customers, please contact your administrator, your Technical Account Manager, or your Microsoft premier account representative.

To post a question or receive community support for developing Windows Store apps, consider posting your question or concern on the Windows Store apps forum.
Posted by LukePuplett on 3/24/2014 at 4:46 AM
The more I think about it, the more upset I get. You can't blackmail your customers by threatening to not to fix their bug if they can't jump when you shout. Of course, the newsflash is that this is not MY bug.

Look, I found someone else with the issue and I think there's a link to a repro .zip there.

I've been helping MS with betas and making repro apps, even having Skype chats with people on one Redmond team, but you CANNOT go around giving ridiculously short deadlines on obtaining FREE HELP from the paying customer! And we do pay for your software and we do add value to your app store, ecosystem and bottom line.
Posted by LukePuplett on 3/24/2014 at 4:39 AM
Well that's one way to ensure you never have to fix any bugs. Just bounce them back to us. I mean its your problem and let's face it I only charge £600/day for my time, so yeah I'll run around making repro apps for you. Or maybe I won't, maybe I'll just buy a Mac or write Android apps.

How can you a) waste people's time enough with the bug and working around it and then b) seriously expect people to run around again making a repro app in double-quick time?
Posted by Microsoft on 3/24/2014 at 3:55 AM
Hello again. We wanted to give you a quick reminder that to efficiently investigate and reproduce your issue, we need you to submit the additional information we requested. If we haven't heard back from you with the requested information in the next 3 days, we will go ahead and close the issue.
Posted by Microsoft on 3/18/2014 at 11:20 PM
Thank you for submitting feedback on Visual Studio and .NET Framework. In order to efficiently investigate and reproduce this issue, we are requesting additional information outlined below.

Could you please give us a demo project to demonstrate this issue so that we can conduct further research?

Please submit this information to us within 4 business days. We look forward to hearing from you with this information. If you require immediate assistance with this issue, please contact product support at

Microsoft Visual Studio Connect Support Team
Posted by Microsoft on 3/18/2014 at 10:53 AM
Thank you for your feedback, we are currently reviewing the issue you have submitted. If you require immediate assistance with this issue, please contact product support at