This forum thread is the general topic for Telerik UI for Xamarin.
The code you've shared does not appear to be for Xamarin.Forms (there is no Header property in Xamarin.Forms). Additionally, Xamarin.Forms does not have a TextBlock control. Therefore, I am assuming you are using UWP and the UI for UWP DataGrid?
If I'm correct, please post in the UI for UWP - DataGrid
forums. If I'm incorrect and this is for Xamarin.Forms, please send an updated code snippet and I'll be happy to assist further.
Normally, I could change the forum for you. However, since this thread originated by someone else under Telerik UI for Xamarin, you will need to re-post.
Note About Licensing and Post Location
I do not see any license for your account and you've never downloaded any Telerik product or held any Telerik license (with this account). If you are using the open source version instead of the commercial version of UI for UWP, please post this on StackOverflow (with a UI for UWP tag) or as a GitHub Issue (on the UI for UWP repo).
Although you can post in the UI for UWP forum, you would likely receive a faster answer on StackOverflow or GitHub as the forums and Support Ticket system are for the commercial version of Telerik UI for UWP.
I wish you the best of luck finding a happy solution.
Lance | Technical Support Engineer, Principal
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