I wanted to report that, when the Filtermode.Simple is active and you have a bool column, the checkbox control that filters data on top of the column, does not work properly.
In particular, when you click it, data are filtered, but the control always shows the "unchecked" status.
this is very very strange... I found the problem in my project, so before opening this thread I did a test with an empty project.
I have created a new Blazor Server Project in .NET 5.0, and added a reference to the Radzen.Blazor library, version 3.13.4.
Then I modified the standard example of Microsoft in the "fetchdata" page, using the RadzenDataGrid instead the table. Also in that case I have the problem.
same behavior... I am perplexed...
I haven't done anything special, the project is empty and my code looks similar to yours. There must be something wrong somewhere else... I will compare it with your demo.
I have found where the problem could be.
In the demo, in the_Host.cshml page there is:
<link href="_content/Radzen.Blazor/css/standard.css" rel="stylesheet">
<!-- Include the base version if you are using Bootstrap already
<link rel="stylesheet" href="css/bootstrap/bootstrap.min.css" />
<link href="_content/Radzen.Blazor/css/default-base.css" rel="stylesheet">
-->
In the demo you use the standard.css file. In my project, since I already use bootstrap I use the default-base.css.
If I use the standard.css file the component works, but actually I'm using bootstrap, so I I should continue to use the default-base.css and the component should work also in this case.
Because with the default-base.css + bootstrap.min.css the icon in the checkbox header of the column does not appear. The filter works, but the checkbox is always empty: