DataGrid grouping does not work for my bindings

Hi Jason,

Sorry for so many postings as of late. You can regard this one as lower priority. As I have described in past postings, I generally set the Columns.DisplayMemberBinding to a binding that is typically based on a PropertyDescriptor (which may or may not wrap a PropertyInfo). I think the reason it doesn't work for grouping is that the DataGrid.UpdateGrouping method appears to only consider Column.PropertyInfo.Name (and it does is twice for some reason), which gives just the useless "(0)". Therefore, the GroupDescriptions are unable to get the property values. The GroupDescription appears to be rather inflexible, and I noticed your comment:

    // TODO: The performance of groupDescription.GroupNameFromItem is terrible, so we have this workaround.
    //       This bypasses the StringComparison and Converter properties which makes it seem pointless to use GroupDescription.
    //       Need to decide what the grouping API should be. But it's internal for now so can sort it out later.

So I am hoping you might be able to redesign this to work with my bindings, or expose some way I can supply a function to get property values for a column.

Thanks

Peter

Hello Peter

I had been experimenting with using GroupDescription in hopes to reduce coupling between DataGridItemsSource/DataGridColumn, make testing easier, and make it possible to programatically group by a property, rather than relying on an existing DataGridColumn instance. But as you noted, I ended up running into limitations and performance issues. I have not lost hope on this direction though as I have solved similar issues before, but I have parked it for now. In the next nightly build I have somewhat restored the previous implementation enough for DisplayMemberBinding columns to group correctly again.

-Jason Fauchelle

Hi Jason,

As always, thanks for the quick response. I will try the new version.

Thanks

Peter

Hi Jason,

I have confirmed that grouping seems to be working very well now with my bindings.

Thanks

Peter