The HorizontalAlignment is for the content of the element, not for the element itself.
This being said, you can increase the width of the margin, which will indent the DetailGrid. Note however that the TreeLine will not be aligned anymore, so you would have to hide it ( DataRowTemplate.ShowTreeLine = false).
I don’t know your scenario, but another solution would be to nest the second DetailGrid to the first one, instead of adding it to the master grid. This way the indent and the TreeLine would all be fine.
e.g. detailGridTemplate1.DetailGridTemplates.Add( new DetailGrid() ).
Imported from legacy forums. Posted by André (had 976 views)