There is probably a very simple flag for this... I have a dataset that comes presorted, it has a column called IsFavorite.  Imagine

true result1
true result2
false result3
true result4
false result5

When I group by IsFavorite and take the empty sort OR apply the ascending sort, I see (correctly)

IsFavorite: false
false result3
false result5

IsFavorite: true
true result1
true result2
true result4

However, if I apply the descending sort, the entire result set gets flipped upside down!

IsFavorite: true
true result4
true result2
true result1

IsFavorite: false
false result5
false result3

What I can do to preserve the original sort order when changing the group sort order?  In this case I've used numerical results, but imagine how it looks when the results were alphabetically sorted originally!

Thank you in advance. 

Respectfully,

Tim 

Hi Tim,

You can choose to sort by more than one Column and choose how to sort. So you can click on IsFavorite (descending) and then hold the Shift key and click on the Result column (Ascending). With this way, the user can choose to sort by as many columns as they want. This will also save a lot of overhead in order to program a default behavior and then have the user change it by sorting by multiple columns.

Dear Marc,

I understand that the user can select another column to sort by, but it is still wierd.  Imagine instead fruits:

non-tropical apple 
tropical banana
tropical durian
non-tropical pear

If you group by tropical, without sorting by the name, it should become

non-tropical
- apple
- pear

tropical
- banana
- durian

If the user decides, oh, I want to see tropical at the top, and clicks the group to sort, anyone's expectation would be

tropical

- banana
- durian

 non-tropical
- apple
- pear

In my case, I have a Chinese dictionary with a particular sort order.  Having it flip upside down when the favorites is at the top vs the bottom is really wierd and undesireable.  If there is any help you can provide for this (anyone) it would be very much appreciated. 

Hi Tim, 

This in fact was a design decision as we "reverse" the sorting for optimization so that we do not re-sort the rows, we simply flip them. 

We understand that in certain scenarios that would give an undesirable feel as in your case.

What we can suggest is that when you sort on the grouped column, to handle the PreviewMouseDown event on that ColumnManagerRow and force a sorting on your other column to un-reverse it.

You can handle the previewMouseDown event through a style that targets ColumnManagerCell with an EventSetter.

You can access the sort descriptions and change them through the SortDescriptions property on the DataGridCollectionViewSource: 

  (myGrid.ItemsSource as DataGridCollectionViewSource).SortDescriptions 

I hope this helps.