Datagridview bound checkbox column - with check all not working

I have a sortableBindingList(of Order) as the datasource to a datagridview.

The Order object has a isSelected boolean property.

dim lst as new sortableBindingList(of object)

fill list….

datagridview.datasource = lst

I also have a “check all” button.  When I press the button, I want to loop through the list and set the property

for each row in lst

row.isSelected = true

next

datagridview.datasource = lst

The property is getting set in the sortableBindingList(of order) but the checkboxes in the datagridview don’t change.

I am not sure what I am doing wrong.

Note: I am using the SortableBindingList because that is how I do it in our WinForm application.  If I should not be  using a SortableBindingList let me know.

Thanks,

Shawn R