Expand only one group on render of a datagrid

[Pierre-Louis_Vernay]

Greetings,

I'm trying to build a datagrid grouped by 2 objects (project and user). I want this grid to look like this at first, with the project group expanded and the user group collapsed. But I still want the user to be able to expand/collapse a group as he wants.

For the moment, on first render, everything is expanded. Using the GroupRowRender parameter, I obtained the result i'm looking for but the user is not able anymore to expand or collapse a row. WHat's the solution?

[enchev]

Here is something I’ve this morning for a customer with similar requirements using this demo:

Blazor DataGrid grouping API

[Pierre-Louis_Vernay]

Thank you so much. I made some modifications because with this solution I wasn't able to expand your city group at all.

Now the first render has the good design and I can expand and collapse any row.