TreeDataGrid: How to set first row "IsSelected = true"

[bsdRuf]

Hello,

i am building my TDG dynamicly. By creating custom FileTreeNodeModels. I tried to set the IsSelected in there but that didnt work.

TreeDataGridRow.IsSelected = true;

But TreeDataGridRow.IsSelected is only a getter. From the F12 I could see there is a CLR Prop which I could set in the F12 GUI but I dont know how to set it by the constructor of the window.

Simply its just to select/highlight the first entry of my TDG (its used as navigation - somehow like the windows 11 views)
Any idea or advice is highly appreciated

[timunie]

myTreeDataGrid.RowSelection.Select(idx) iirc

[bsdRuf]

Your memory is awsome, thank you