[Solved] Virtualizing RadGridView

[Karl]

Hello,

I have a GridView in which I am loading about 20 thousand records and 4 columns. The UI draws the Grid in about 2 seconds, however the scrolling is not smooth like in the 50 million record demo.

Here is my grid xaml, is there anything obvious I am missing that needs to be defined to get gridview to have better performance?

<grid:RadGridView   x:Name="GeographyRadGridView"
                                ItemsSource="{Binding GeographyDataLoaded}"
                                Grid.Row="1"
                                IsReadOnly="True"
                                AutoGenerateColumns="False"
                                CanUserFreezeColumns="False"
                                ShowGroupPanel="False" MinWidth="400" MinHeight="300" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch" MaxHeight="500">
// ...
</grid:RadGridView>

[Vlad]

Hello,

 Since you do not have auto-generated columns can you clarify what kind of columns are added in the grid? Do you have some heavy CellTemplate or CellStyle? 

Greetings,
Vlad
the Telerik team

[Karl]

There are 3 combo box CellTemplates, with County, State and City values. 1, 69, and ~30,000 options respectively. The last column is a simple text field with a zip code.

I went ahead and tested changing the city binding to a text field like so: 

<grid:GridViewDataColumn Width="Auto"
Header="City"

TextAlignment="Right"

DataMemberBinding="{Binding City}">

                   </grid:GridViewDataColumn>

This did not have produce any change in the way scrolling appears in the UI? Do you have any recommendations?

Karl 

[Vlad]

Hello,

Are you using VirtualizingStackPanel for these combos? Here is an example:
...
<telerik:RadComboBox.ItemsPanel>
      <ItemsPanelTemplate>
            <VirtualizingStackPanel />
      </ItemsPanelTemplate>
</telerik:RadComboBox.ItemsPanel>

....

Best wishes,
Vlad
the Telerik team

[Karl]

I added the code snippet like you suggested, with no difference. Below is the full column definition.

<!-- City -->
<grid:GridViewDataColumn Width="Auto"
                         Header="City"
                         TextAlignment="Right"
                         DataMemberBinding="{Binding City}">
    <grid:GridViewDataColumn.CellTemplate>
        <DataTemplate>
            <telerikInput:RadComboBox ItemsSource="{Binding Cities}"
                                      SelectedValue="{Binding City, Mode=TwoWay}"
                                      SelectedValuePath="DisplayText"
                                      DisplayMemberPath="DisplayText"
                                      IsEnabled="{Binding IsFound, Converter={StaticResource booleanToOppositeConverter}}">
                <telerikInput:RadComboBox.ItemsPanel>
                    <ItemsPanelTemplate>
                        <VirtualizingStackPanel />
                    </ItemsPanelTemplate>
                </telerikInput:RadComboBox.ItemsPanel>
            </telerikInput:RadComboBox>
        </DataTemplate>
    </grid:GridViewDataColumn.CellTemplate>
</grid:GridViewDataColumn>

[Karl]

I've upgraded to the most recent release Jan 2011, and found that the scrolling is much improved. I also removed the combo boxes, and the scrolling was even better.

Karl