Virtualization loads all items for each group

2 posts, 0 answers
  1. Markus
    Markus avatar
    13 posts
    Member since:
    Sep 2013

    Posted 28 Aug 2014 Link to this post

    I bound a RadGridView to a VirtualQueryableCollectionView backed by SQL using System.Data.Linq.ITable.

    At first Virtualization works nicely as I see that the LoadSize is submitted to the SQL provider (tracing SQL queries).
    Once I add grouping (dragging a column into the grouping panel) all rows for each group are loaded. 

            <telerik:RadGridView x:Name="Table" ItemsSource="{Binding Data}" AutoGenerateColumns="False" IsReadOnly="True" 
                                 Height="500" Width="500"
                                 GroupRenderMode="Flat"
                                 CanUserInsertRows="False" CanUserDeleteRows="False"
                                 EnableRowVirtualization="True" EnableColumnVirtualization="True"
                                 ScrollMode="Deferred"/>

    Is UI virtualization supported in a group scenario? Am I missing some settings?
  2. Dimitrina
    Admin
    Dimitrina avatar
    3769 posts

    Posted 29 Aug 2014 Link to this post

    Hello,

    The default grouping is the one that occurs as the user drags a column header and drops it into the GroupPanel. Then, we internally generate and execute a LINQ query appending a GroupBy clause to the source collection.

    WCF RIA Services do not support true server-side grouping. They translate it to sorting instead. The grouping is done solely on the client by RadGridView and that why all the items need to be downloaded.


    Regards,
    Didie
    Telerik
     
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