Grouping, sorting, filtering in Data Virtualization

[Denis]

Hi!
Can I group, sort and filter data in a Data Virtualization? Before data fully loaded on the client.

Thanks.

[Vlad]

Hi,

Currently grouping is not supported however you can sort and filter on the server using ItemsLoading event - please check this help article for more info. With our first service pack (middle of December) we will provide extension methods for EntityQuery and you will able to use the collection SortDescriptors and FilterDescriptors directly with WCF RIA Services. For example:

view.ItemsLoading += (s, e) =>
           {
               context.Load<Order_Detail>(query.Where(view.FilterDescriptors).Sort(view.SortDescriptors).Skip(e.StartIndex).Take(e.ItemCount)).Completed += (sender, args) =>
              {
                  var lo = (LoadOperation)sender;
                  if (lo.TotalEntityCount != -1 && lo.TotalEntityCount != view.VirtualItemCount)
                  {
                      view.VirtualItemCount = lo.TotalEntityCount;
                  }
                  view.Load(e.StartIndex, lo.Entities);
              };
           };

Sincerely yours,
Vlad
the Telerik team

[Denis]

Thanks

[Srujana]

Hello Vald,

I get the following error when I tried adding

.Where(view.FilterDescriptors).Sort(view.SortDescriptors).

to my query, it works fine otherwise on loading data virtually, But sorting and filtering doesn't work. I am using SL4 and RIA, VS 2010.

Instance argument: cannot convert from 'System.ServiceModel.DomainServices.Client.EntityQuery<SilverlightApplication1.Web.GridSpecific>' to 'System.Linq.IQueryable' C:\Documents and Settings\sxc0k6l\Desktop\tempFiles\SilverlightApplication1\SilverlightApplication1\MainPage.xaml.cs

Thanks in advance,
Srujana.

[Vlad]

Hello,

 You will need our extension methods. You can check this demo (and your local copy) for more info. You can check my blog post as well. 

Kind regards,
Vlad
the Telerik team

[Srujana]

Thanks Vlad.  I got this to work. I have another question though.

Now I would like to add a 'search as you type' textbox functionality on my grid as the demo says  here.

Is it possible to handle the filtering on headers and this composite filtering(explained in the demo) at the same time on the grid that is using data Virtualization.

If you have any blog post or code sample that explains more on this, Please let me know.

Thanks,
Srujana.

[Tsvyatko]

Hello Srujana,

i have modified the example from the blog post mentioned earlier adding search as you type. Please have a look at the example and let me know if you have any further questions

Regards,
Tsvyatko
the Telerik team

[Srujana]

Thanks, I will check this out and let you know if I see any issues.

[David]

Hey all
The support of grouping and sorting on the data virtualization source, is this feature now available for the release Q1 2011 ?
Thanks for replay.

Kind regards
Dave