Last Updated: 14 Aug 2019 07:25 by ADMIN
Created by: Tel
Comments: 1
Category: GridView
Type: Feature Request
Hello, i am using the GridViewSpreadStreamExport to export a gridview with parent and child rows.
Everithing works fine but is it possible to set the parent row to collapsed, if there are child rows?
Last Updated: 02 Aug 2019 14:04 by ADMIN
Created by: Roger
Comments: 1
Category: GridView
Type: Feature Request

I might be missing something, but I have Hyperlinks in a column in my RadDatGridView.


I tried searching for a Support document explaining this, but didn't find any.


When the grid is exported to excel all data is coming across, but the column with hyperlink is not

a hyperlink in Excel.


Below is sample of the code used to make the "HyperLink" column in my grid.

                radGridView1.DataSource = dtResults;
                GridViewHyperlinkColumn col = new GridViewHyperlinkColumn();
                radGridView1.Columns.Insert(5, col);
                col.Width = 200;
                col.FieldName = "Path";
                col.HeaderText = "Path";
                col.Name = "Path";


Coded used to do the Export....

               GridViewSpreadExport spreadExporter = new GridViewSpreadExport(this.radGridView1);
                spreadExporter.ExportVisualSettings = true;
                SpreadExportRenderer exportRenderer = new SpreadExportRenderer();

                spreadExporter.RunExport(filename, exportRenderer);





Last Updated: 18 Jul 2019 11:45 by ADMIN


In our Environment it's not possible to assign a GroupComparer to another GridView template then MasterTemplate. The GroupComparer property is always null after assignment.

It's possible to assign our custom comparer to the MasterTemplate and it will be triggered, but not in another template then MasterTemplate.

Best regards.

Tassilo Koller | Dipl. Informatiker (FH) | IT-Softwareentwicklung

[T] +49 (0)8233 381 383

[E] | [W]

FORUM MEDIA GROUP GMBH| Mandichostraße 18 | 86504 Merching | [T] +49 (0)8233 381-0 | [F] + 49 (0)8233 381-222 | [W]| Sitz der Gesellschaft: Merching | Register: AG Augsburg HRB 11537 | Geschäftsführer: Magdalena Balanicka, Norbert Bietsch, Roland Hradek, Mihaela Mravlje | Beirat: Ronald Herkert (Vorsitzender)

Elektronische Rechnungen bitte an folgende Adresse senden:

Under Review
Last Updated: 17 Jul 2019 14:00 by ADMIN

Using a custom control using the Telerik Presentation Framework, I am receiving a NullException inside the GridCheckBoxHeaderCellElement during the GridViewElement's data load.

The custom control construction follows an example I found somewhere (reference is lost to me at this point):

ControlContainingGridView inherits from RadControl

CreateChildItems creates and adds ControlContainingGridViewElement


ControlContainingGridViewElement inherits from RadElement

CreateChildItems creates and adds some layout controls AND a GridViewElement


public partial class ControlContainingGridView : RadControl {
        public ControlContainingGridView() {
            this.TextChanged += ControlContainingGridView_TextChanged;

        private void ControlContainingGridView_TextChanged(object sender, EventArgs e) {
            controlContainingGridViewElement.Text = this.Text;

        private ControlContainingGridViewElement controlContainingGridViewElement = null;

        protected override void CreateChildItems(RadElement parent) {
            controlContainingGridViewElement = new ControlContainingGridViewElement();

        public object DataSource {
            get {
                return controlContainingGridViewElement.GridView.Template.DataSource;
            set {
                try {
                    controlContainingGridViewElement.GridView.Template.DataSource = value;
                } catch (Exception ex) {

        internal void SetupColumns(Action<MasterGridViewTemplate> setupColumns) {
            controlContainingGridViewElement.GridView.Template.AutoGenerateColumns = false;


    public class ControlContainingGridViewElement : RadElement {

        private TextPrimitive textPrimitive = null;
        private RadButtonElement addButton = null;
        private RadButtonElement deleteButton = null;
        private RadGridViewElement gridViewElement = null;

        public RadGridViewElement GridView { get { return gridViewElement; } }

        public bool ShowAddButton { get { return addButton.Visibility == ElementVisibility.Visible; } set { addButton.Visibility = value ? ElementVisibility.Visible : ElementVisibility.Collapsed; } }
        public bool ShowDeleteButton { get { return deleteButton.Visibility == ElementVisibility.Visible; } set { deleteButton.Visibility = value ? ElementVisibility.Visible : ElementVisibility.Collapsed; } }

        public string Text { get { return textPrimitive.Text; } set { textPrimitive.Text = value; } }

        protected override void CreateChildElements() {
            DockLayoutPanel dlp = new DockLayoutPanel();
            dlp.StretchHorizontally = true;
            dlp.StretchHorizontally = true;
            dlp.LastChildFill = true;

            DockLayoutPanel dlpBar = new DockLayoutPanel();
            dlpBar.StretchHorizontally = true;
            DockLayoutPanel.SetDock(dlpBar, Dock.Top);

            var imagePrimitive = new ImagePrimitive();
            DockLayoutPanel.SetDock(imagePrimitive, Dock.Left);

            textPrimitive = new TextPrimitive();
            DockLayoutPanel.SetDock(textPrimitive, Dock.Left);

            var slp = new StackLayoutPanel();
            DockLayoutPanel.SetDock(slp, Dock.Right);

            var addButton = new RadButtonElement {
                Text = "Add",
                MaxSize = new Size() { Height = 20 }
            var deleteButton = new RadButtonElement {
                Text = "Del",
                MaxSize = new Size() { Height = 20 }



            gridViewElement = new RadGridViewElement {
                StretchHorizontally = true,
                StretchVertically = true
            gridViewElement.Template.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill;
            gridViewElement.Template.AllowAddNewRow = false;
            gridViewElement.Template.AllowDeleteRow = false;
            gridViewElement.Template.AllowDragToGroup = false;
            gridViewElement.ShowGroupPanel = false;
            gridViewElement.ShowGroupPanelScrollbars = false;





During Form load, I programmatically add columns and provide a binding source


private List<SampleModel> sampleModels = new List<SampleModel>();
        private BindingSource sampleModelsBinding = new BindingSource();

        private void RadForm1_Load(object sender, EventArgs e) {

            sampleModels.Add(new SampleModel() {
                When = DateTime.Parse("1980-04-23"),
                SomeText = "Purple Bananas",
                IsTrue = true
            sampleModels.Add(new SampleModel() {
                When = DateTime.Parse("2002-07-20"),
                SomeText = "Ball & Chain",
                IsTrue = false
            sampleModelsBinding.DataSource = sampleModels;

            controlContainingGridView.SetupColumns((grid) => {
                grid.AddDateTimeColumn(nameof(SampleModel.When), "When");
                grid.AddTextBoxColumn(nameof(SampleModel.SomeText), "Some Text");
                grid.AddCheckBoxColumn(nameof(SampleModel.IsTrue), "Is True");

            controlContainingGridView.DataSource = sampleModelsBinding;



Inclusion of the CheckBox column results in the following error:

Exception thrown: 'System.NullReferenceException' in Telerik.WinControls.GridView.dll

System.NullReferenceException: Object reference not set to an instance of an object.
   at Telerik.WinControls.UI.GridCheckBoxHeaderCellElement.Attach(GridViewColumn data, Object context)
   at Telerik.WinControls.UI.BaseVirtualizedContainer`1.InsertElement(Int32 position, IVirtualizedElement`1 element, T data)
   at Telerik.WinControls.UI.BaseVirtualizedContainer`1.UpdateElement(Int32 position, T data)
   at Telerik.WinControls.UI.BaseVirtualizedContainer`1.MeasureElements()
   at Telerik.WinControls.UI.BaseVirtualizedContainer`1.MeasureOverride(SizeF availableSize)
   at Telerik.WinControls.RadElement.MeasureCore(SizeF availableSize)
   at Telerik.WinControls.RadElement.Measure(SizeF availableSize)
   at Telerik.WinControls.UI.GridVirtualizedRowElement.MeasureElements(SizeF availableSize, SizeF clientSize, Padding borderThickness)
   at Telerik.WinControls.UI.LightVisualElement.MeasureOverride(SizeF availableSize)
   at Telerik.WinControls.UI.GridRowElement.MeasureOverride(SizeF availableSize)
   at Telerik.WinControls.RadElement.MeasureCore(SizeF availableSize)
   at Telerik.WinControls.RadElement.Measure(SizeF availableSize)
   at Telerik.WinControls.UI.VirtualizedStackContainer`1.MeasureElementCore(RadElement element, SizeF availableSize)
   at Telerik.WinControls.UI.ScrollableRowsContainerElement.MeasureElementCore(RadElement element, SizeF availableSize)
   at Telerik.WinControls.UI.VirtualizedStackContainer`1.MeasureElement(IVirtualizedElement`1 element)
   at Telerik.WinControls.UI.PinnedRowsContainerElement.MeasureElement(IVirtualizedElement`1 element)
   at Telerik.WinControls.UI.BaseVirtualizedContainer`1.MeasureElements()
   at Telerik.WinControls.UI.BaseVirtualizedContainer`1.MeasureOverride(SizeF availableSize)
   at Telerik.WinControls.UI.ScrollableRowsContainerElement.MeasureOverride(SizeF availableSize)
   at Telerik.WinControls.RadElement.MeasureCore(SizeF availableSize)
   at Telerik.WinControls.RadElement.Measure(SizeF availableSize)
   at Telerik.WinControls.UI.RowsContainerElement.MeasureOverride(SizeF availableSize)
   at Telerik.WinControls.RadElement.MeasureCore(SizeF availableSize)
   at Telerik.WinControls.RadElement.Measure(SizeF availableSize)
   at Telerik.WinControls.UI.ScrollViewElement`1.MeasureViewElement(SizeF availableSize)
   at Telerik.WinControls.UI.ScrollViewElement`1.MeasureView(SizeF availableSize)
   at Telerik.WinControls.UI.ScrollViewElement`1.MeasureOverride(SizeF availableSize)
   at Telerik.WinControls.UI.GridTableElement.MeasureOverride(SizeF availableSize)
   at Telerik.WinControls.RadElement.MeasureCore(SizeF availableSize)
   at Telerik.WinControls.RadElement.Measure(SizeF availableSize)
   at Telerik.WinControls.Layouts.DockLayoutPanel.MeasureOverride(SizeF constraint)
   at Telerik.WinControls.RadElement.MeasureCore(SizeF availableSize)
   at Telerik.WinControls.RadElement.Measure(SizeF availableSize)
   at Telerik.WinControls.Layouts.ContextLayoutManager.UpdateLayout()
   at Telerik.WinControls.UI.GridVisibilityHelper.EnsureRowVisible(GridViewRowInfo rowInfo)
   at Telerik.WinControls.UI.GridTableElement.EnsureRowVisible(GridViewRowInfo rowInfo)
   at Telerik.WinControls.UI.GridTableElement.EnsureCellVisible(GridViewRowInfo rowInfo, GridViewColumn column)
   at Telerik.WinControls.UI.GridTableElement.UpdateViewCore(Object sender, DataViewChangedEventArgs args)
   at Telerik.WinControls.UI.GridTableElement.UpdateView(Object sender, DataViewChangedEventArgs args)
   at Telerik.WinControls.UI.GridTableElement.ProcessTemplateEvent(GridViewEvent eventData)
   at Telerik.WinControls.UI.GridTableElement.Telerik.WinControls.UI.IGridViewEventListener.ProcessEvent(GridViewEvent eventData)
   at Telerik.WinControls.UI.GridViewEventProcessEntity.ProcessCollection(GridViewEvent gridEvent, PriorityWeakReferenceList list, GridEventProcessMode processMode)
   at Telerik.WinControls.UI.GridViewEventProcessEntity.ProcessEvent(GridViewEvent gridEvent)
   at Telerik.WinControls.UI.GridViewSynchronizationService.NotifyListeners(GridViewEvent gridEvent)
   at Telerik.WinControls.UI.GridViewSynchronizationService.FlushEvents()
   at Telerik.WinControls.UI.GridViewSynchronizationService.DispatchEvent(GridViewEvent gridEvent)
   at Telerik.WinControls.UI.GridViewSynchronizationService.RaiseCurrentChanged(GridViewTemplate template, GridViewRowInfo row, GridViewColumn column, Boolean user)
   at Telerik.WinControls.UI.GridViewTemplate.CollectionView_CurrentChanged(Object sender, EventArgs e)
   at System.EventHandler.Invoke(Object sender, EventArgs e)
   at Telerik.WinControls.Data.RadCollectionView`1.OnCurrentChanged(EventArgs args)
   at Telerik.WinControls.Data.RadCollectionView`1.SetCurrentPositionCore(Int32 newPosition, Boolean forceNotify, CurrentChangeReason reason)
   at Telerik.WinControls.Data.RadListSource`1.InitializeCurrentItem()
   at Telerik.WinControls.Data.RadListSource`1.Initialize()
   at Telerik.WinControls.Data.RadListSource`1.Bind(Object dataSource, String dataMember)
   at Telerik.WinControls.Data.RadListSource`1.set_DataSource(Object value)
   at Telerik.WinControls.UI.GridViewTemplate.set_DataSource(Object value)
   at BugReproduction.ControlContainingGridView.set_DataSource(Object value) in ...\BugReproduction\BugReproduction\ControlContainingGridView.cs:line 42

Last Updated: 17 Jul 2019 07:33 by ADMIN
Release R3 2019 (LIB 2019.2.722)
Last Updated: 15 Jul 2019 08:33 by ADMIN
Release R3 2019 (LIB 2019.2.722)
Created by: Daniel
Comments: 1
Category: GridView
Type: Bug Report

Steps to reproduce:

  1. Click column header to sort.
  2. Click button which to export to Excel.
  3. The rows return to unsorted.
  4. Scroll down slightly and scroll back up and the sort is restored.

This happens after calling RunExport.

I attached a gif and a sample project.

Last Updated: 08 Jul 2019 08:43 by ADMIN
Add a combo-box column that point to a field with Guid data type, add summary item to this columns as well.


private void RadGridView1_CreateRowInfo(object sender, GridViewCreateRowInfoEventArgs e)
    if (e.RowInfo is GridViewSearchRowInfo)
        e.RowInfo = new MySerachRow(e.ViewInfo);

class MySerachRow : GridViewSearchRowInfo
    public MySerachRow(GridViewInfo viewInfo) : base(viewInfo)

    public override string GetCellFormattedValue(GridViewRowInfo row, GridViewColumn column)
        if (row is GridViewSummaryRowInfo)
            return "";
        return base.GetCellFormattedValue(row, column);
Last Updated: 01 Jul 2019 15:04 by ADMIN
Release R3 2019 (LIB 2019.2.708)

UI for WinForms R2 2019 SP1 (version 2019.2.618)

June 19, 2019


  • New property inside GridViewSearchRowInfo: DeferredSearch. Gets or sets a value indicating whether grid will wait until enter key is pressed before it starts a search.



I have implemented this and it is exactly what I want and need, Thank you! 
However I thought I might point out that when you tab out it doesn't implement the search, only when you press enter.

And when you press the X to clear the search it clears the text box but not the search. the count of found and the highlighted finds remain 

Last Updated: 28 Jun 2019 08:50 by ADMIN
Release R2 2019 SP1
Created by: Sasa
Comments: 2
Category: GridView
Type: Bug Report
RadGridView data source contains date values from years 2018 and 2019. After adding Excel like filters to the RadGridView and selecting year 2019 no rows were displayed, even though some values did match the filter condition (see attachment).
Last Updated: 27 Jun 2019 09:53 by ADMIN
Add a new DeferredFilter property on RadGridView level which controls whether the filtering logic will be immediately preformed on each key stroke or only by pressing Enter.
Under Review
Last Updated: 27 Jun 2019 09:40 by ADMIN

Please refer to the attached gif file. You will notice that for the GridViewMaskBoxColumn  with numeric mask the filtering doesn't work. For the other columns each key stroke filters the grid rows.

Workaround: either use a GridViewDecimalColumn or change the default editor for the GridViewMaskBoxColumn :

            this.radGridView1.EditorRequired += radGridView1_EditorRequired; 

        private void radGridView1_EditorRequired(object sender, EditorRequiredEventArgs e)
            if (this.radGridView1.CurrentColumn.HeaderText == "MaskBoxColumn")
                GridSpinEditor spinEditor = new GridSpinEditor();
                RadSpinEditorElement element = spinEditor.EditorElement as RadSpinEditorElement;
                element.ShowUpDownButtons = false;
                e.Editor = spinEditor;



Last Updated: 19 Jun 2019 09:46 by ADMIN
Created by: Dimitri
Comments: 3
Category: GridView
Type: Bug Report

In my gridview need support of different heights of rows. I solved it with the autosize property.

But now I have a side action that the header row and filter row also react to the autosize property.

Attached you can see this behaviour...

Here my code:

Grid.MasterView.TableFilteringRow.MinHeight = 40
Grid.AutoSizeRows = True

Is there a chance to separate data rows from filter and header row?




Last Updated: 06 Jun 2019 13:44 by ADMIN
Release R2 2019 SP1 (LIB 2019.2.610)
Created by: Comparto
Comments: 1
Category: GridView
Type: Feature Request
Add deferred search like in WPF suite
Last Updated: 06 Jun 2019 13:28 by ADMIN
Release R2 2019 SP1 (LIB 2019.2.610)
Created by: James
Comments: 1
Category: GridView
Type: Bug Report

To reproduce:

- Set the AutoSize to true

- Add GroupDescriptor

- An InvalidOperationException is thrown

Last Updated: 06 Jun 2019 13:25 by ADMIN
Release R2 2019 SP1 (LIB 2019.2.610)
To reproduce:

Sub New()

    Dim dt1 As New DataTable
    dt1.Columns.Add("Id", GetType(Integer))
    dt1.Columns.Add("Name", GetType(String))
    For index = 1 To 20
        dt1.Rows.Add(index, "Parent" & index)
    Me.RadGridView1.MasterTemplate.DataSource = dt1
    Me.RadGridView1.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill

    Dim dt2 As New DataTable
    dt2.Columns.Add("Id", GetType(Integer))
    dt2.Columns.Add("Name", GetType(String))
    dt2.Columns.Add("ParentId", GetType(Integer))

    Dim dt3 As New DataTable
    dt3.Columns.Add("Id", GetType(Integer))
    dt3.Columns.Add("Name", GetType(String))
    dt3.Columns.Add("ParentId", GetType(Integer))
    For index = 1 To 20
        If index Mod 2 = 0 Then
            dt2.Rows.Add(index, "Child1." & index, index)
            If index Mod 4 = 0 Then
                dt3.Rows.Add(index, "Child2." & index, index)
            End If
        ElseIf index Mod 3 = 0 Then
            dt3.Rows.Add(index, "Child2." & index, index)
            dt3.Rows.Add(index, "Child2." & index, index)
        End If


    Dim template As New GridViewTemplate()
    template.DataSource = dt2
    template.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill

    Dim relation As New GridViewRelation(RadGridView1.MasterTemplate)
    relation.ChildTemplate = template
    relation.RelationName = "FirstChild"

    Dim template2 As New GridViewTemplate()
    template2.DataSource = dt3
    template2.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill

    Dim relation2 As New GridViewRelation(RadGridView1.MasterTemplate)
    relation2.ChildTemplate = template2
    relation2.RelationName = "SecondChild"

    AddHandler Me.RadGridView1.ChildViewExpanding, AddressOf ChildViewExpanding
End Sub

Private Sub RadGridView1_ViewCellFormatting(sender As Object, e As Telerik.WinControls.UI.CellFormattingEventArgs) _
Handles RadGridView1.ViewCellFormatting
    Dim cell As GridDetailViewCellElement = TryCast(e.CellElement, GridDetailViewCellElement)
    Dim expanderCell As GridGroupExpanderCellElement = TryCast(e.CellElement, GridGroupExpanderCellElement)
    If expanderCell IsNot Nothing AndAlso TypeOf e.CellElement.RowElement Is GridDataRowElement Then
        Dim hierarchyRow As GridViewHierarchyRowInfo = DirectCast(expanderCell.RowInfo, GridViewHierarchyRowInfo)
        If Not IsExpandable(hierarchyRow) Then
            expanderCell.Expander.Visibility = Telerik.WinControls.ElementVisibility.Hidden
            expanderCell.Expander.Visibility = Telerik.WinControls.ElementVisibility.Visible
        End If
    ElseIf cell IsNot Nothing Then
        Dim hierarchyRow As GridViewHierarchyRowInfo = DirectCast(DirectCast(cell.RowInfo, GridViewDetailsRowInfo).Owner,  _
        For i As Integer = 0 To cell.PageViewElement.Items.Count - 1
            Dim item As RadPageViewItem = cell.PageViewElement.Items(i)
            Dim viewInfo As GridViewInfo = hierarchyRow.Views(i)
            item.Text = "Child Template " & i
            If viewInfo.ChildRows.Count = 0 Then
                If i = 0 AndAlso i < cell.PageViewElement.Items.Count - 1 Then
                    cell.PageViewElement.Items(i + 1).IsSelected = True
                End If
                item.Visibility = Telerik.WinControls.ElementVisibility.Hidden
                item.Visibility = Telerik.WinControls.ElementVisibility.Visible
            End If
    End If
End Sub

Private Function IsExpandable(hierarchyRow As GridViewHierarchyRowInfo) As Boolean
    For Each view As GridViewInfo In hierarchyRow.Views
        If view.ChildRows.Count > 0 Then
            Return True
        End If
    Return False
End Function


AddHandler Me.RadGridView1.ChildViewExpanding, AddressOf RadGridView1_ChildViewExpanding 
AddHandler Me.RadGridView1.MouseDown, AddressOf RadGridView_MouseDown

Private Sub RadGridView1_ChildViewExpanding(sender As Object, e As ChildViewExpandingEventArgs)
    If lastClicked IsNot Nothing AndAlso e.ParentRow.Equals(lastClicked) Then
        e.Cancel = False
        e.Cancel = True
    End If

End Sub

Dim lastClicked As GridViewRowInfo

Private Sub RadGridView_MouseDown(sender As Object, e As MouseEventArgs)
    Dim expander As GridExpanderItem = TryCast(Me.RadGridView1.ElementTree.GetElementAtPoint(e.Location), GridExpanderItem)
    If expander IsNot Nothing Then
        lastClicked = DirectCast(expander.Parent, GridGroupExpanderCellElement).RowInfo 
    End If 
End Sub
Last Updated: 06 Jun 2019 11:21 by ADMIN
Created by: Radu
Comments: 1
Category: GridView
Type: Bug Report

GridView is not correctly drawn if it's not populated and the theme is set to "TelerikMetro" or "TelerikMetroBlue" (the bottom line is missing). 

Steps to reproduce the behavior: create a RadForm, add a RadGridView to it and set the theme to "TelerikMetro" or "TelerikMetroBlue" by using ThemeResolutionService.ApplicationThemeName.

Last Updated: 05 Jun 2019 12:21 by ADMIN
Last Updated: 24 May 2019 04:56 by ADMIN
The decimal separator is removed when exporting with German culture on Windows Server 2012
Last Updated: 16 May 2019 08:57 by ADMIN
Release R1 2019
Created by: Dimitar
Comments: 0
Category: GridView
Type: Bug Report
To reproduce:
- Add a checkbox column and hide some of the cells.
- Change some values and then click on empty cell.
- Exception occurs in OnMouseDownLeft method (GridRowBeahvior class)


Hide the checkbox only.
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