Performance Issue with Virtualization off

[Dhileep Kumar Sampath]

Hi Telerik Team,
                       We are using gridview in a page and because of merging and disabling few cells based on the context, We turned off virtualization. This in turn is affecting the performance drastically as we are loading 25 rows and 15 columns on average. This takes approximately 4 secs to load the UI screen which we want to reduce to 1 sec. Please let me know if there is any work around.


Grid:

<radgridview:RadGridView x:Name="radgvMatrix"
                                    EnableColumnVirtualization="False"
                                    EnableRowVirtualization="False"
                                    AutoGenerateColumns="False"
                                    RowLoaded="radgvMatrix_RowLoaded">
           <radgridview:RadGridView.Columns>
               <radgridview:GridViewDataColumn Header="Parameter Parent" UniqueName="Parent" DataMemberBinding="{Binding Parent}" IsReadOnly="True" MinWidth="120"/>

               <radgridview:GridViewDataColumn Header="Parameter Name" UniqueName="Parameter" MinWidth="120"/>

               <radgridview:GridViewDataColumn Header="Score1" UniqueName="Score" TextAlignment="Center" DataMemberBinding="{Binding Score1}" IsReadOnly="True" MinWidth="100"/>
               <radgridview:GridViewDataColumn Header="Score2" UniqueName="Score" TextAlignment="Center" DataMemberBinding="{Binding Score2}" IsReadOnly="True" MinWidth="100"/>
               <radgridview:GridViewDataColumn Header="Score3" UniqueName="Score" TextAlignment="Center" DataMemberBinding="{Binding Score3}" IsReadOnly="True" MinWidth="100"/>
               <radgridview:GridViewDataColumn Header="Score4" UniqueName="Score" TextAlignment="Center" DataMemberBinding="{Binding Score4}" IsReadOnly="True" MinWidth="100"/>
           </radgridview:RadGridView.Columns>
       </radgridview:RadGridView>

Data Class:

public class DataRow
   {
       public string Parent
       { get; set; }

       public string Parameter
       { get; set; }

       public int Score1
       { get; set; }

       public int Score2
       { get; set; }

       public int Score3
       { get; set; }

       public int Score4
       { get; set; }
   }

SetData method called from constructor of the Page:

private void SetData()
        {
            DataRows = new ObservableCollection<DataRow>();
            int count = 50;

            for (int i = 0; i < count; i++)
            {
                DataRow row = new DataRow();
                row.Parameter = "Parameter " + i.ToString();
                row.Parent = "Parent " + i.ToString();
                row.Score1 = 1 * i;
                row.Score2 = 2 * i;
                row.Score3 = 3 * i;
                row.Score4 = 4 * i;

                DataRows.Add(row);
            }

            this.radgvMatrix.ItemsSource = DataRows;
        }

Please let me know if you need more info.

Regards,
Dhileep

[Stefan Dobrev]

Hi Dhileep Kumar Sampath,

This performance degradation is expected when virtualization is turned off. My suggestion is to turn it on and use RowLoaded and RowUnloaded events to set your specific properties. In RowLoaded you will set them and in RowUnloaded you will remove your set property values in order for the virtualization to work correctly.

Greetings,
Stefan Dobrev
the Telerik team

[Dhileep Kumar Sampath]

Hi Stefan Dobrev ,
      Thanks for your response. Your suggestion helped me in improving the performance. I have one more issue now. I am using your extension method ChildrenOfType extensively in the RowLoaded events which is causing performance issues. Can you please let me know if this is expected behaviour or is there any alternate way for this?

[Maya]

Hi Dhileep Kumar Sampath,

How exactly are you implementing the ChildrenOfType<> extension method ? It would be great if you could send us a sample project so that we could see your exact requirements and settings. Thus we will be able to suggest you an appropriate optimization mechanism for the application.
 

Greetings,
Maya
the Telerik team

[Makarand]

can u give us an example or can you provide any project for that.

[Maya]

Hi Makarand,

Will it be possible to clarify a bit - what is your sceanrio, what example do you require ? Do you want to work with ChildrendOfType<T>() extension method ? If so, you can check out this blog post for a reference. 
 

Kind regards,
Maya
the Telerik team