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() {
            InitializeComponent();
            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();
            this.RootElement.Children.Add(controlContainingGridViewElement);
            base.CreateChildItems(parent);
        }

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

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



    }

    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 }
            };

            slp.Children.Add(addButton);
            slp.Children.Add(deleteButton);


            dlpBar.Children.Add(slp);
            dlpBar.Children.Add(imagePrimitive);
            dlpBar.Children.Add(textPrimitive);



            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;

            dlp.Children.Add(dlpBar);
            dlp.Children.Add(gridViewElement);



            this.Children.Add(dlp);
            base.CreateChildElements();
        }

    }

 

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

Completed
Last Updated: 17 Jul 2019 07:33 by ADMIN
Release R3 2019 (LIB 2019.2.722)
Completed
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
6

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.

Approved
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.

Workaround: 

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);
    }
}
 
Completed
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

RadGridView

NEW
  • 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 

Completed
Last Updated: 28 Jun 2019 08:50 by ADMIN
Release R2 2019 SP1
Created by: Sasa
Comments: 2
Category: GridView
Type: Bug Report
1
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).
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;
            }
        }

 

 

Approved
Last Updated: 19 Jun 2019 09:46 by ADMIN
Created by: Dimitri
Comments: 3
Category: GridView
Type: Bug Report
1

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?

 

Regards,

Dimitri

Completed
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
1

To reproduce:

- Set the AutoSize to true

- Add GroupDescriptor

- An InvalidOperationException is thrown

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

Sub New()
     
    InitializeComponent()

    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)
    Next
    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)
        Else
            dt3.Rows.Add(index, "Child2." & index, index)
        End If

    Next

    Dim template As New GridViewTemplate()
    template.DataSource = dt2
    template.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill
    RadGridView1.MasterTemplate.Templates.Add(template)

    Dim relation As New GridViewRelation(RadGridView1.MasterTemplate)
    relation.ChildTemplate = template
    relation.RelationName = "FirstChild"
    relation.ParentColumnNames.Add("Id")
    relation.ChildColumnNames.Add("ParentId")
    RadGridView1.Relations.Add(relation)

    Dim template2 As New GridViewTemplate()
    template2.DataSource = dt3
    template2.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill
    RadGridView1.MasterTemplate.Templates.Add(template2)

    Dim relation2 As New GridViewRelation(RadGridView1.MasterTemplate)
    relation2.ChildTemplate = template2
    relation2.RelationName = "SecondChild"
    relation2.ParentColumnNames.Add("Id")
    relation2.ChildColumnNames.Add("ParentId")
    RadGridView1.Relations.Add(relation2)

    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
        Else
            expanderCell.Expander.Visibility = Telerik.WinControls.ElementVisibility.Visible
        End If
    ElseIf cell IsNot Nothing Then
        Dim hierarchyRow As GridViewHierarchyRowInfo = DirectCast(DirectCast(cell.RowInfo, GridViewDetailsRowInfo).Owner,  _
        GridViewHierarchyRowInfo)
        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
            Else
                item.Visibility = Telerik.WinControls.ElementVisibility.Visible
            End If
        Next
    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
    Next
    Return False
End Function

Workaround:

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
    Else
        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
Approved
Last Updated: 06 Jun 2019 11:21 by ADMIN
Created by: Radu
Comments: 1
Category: GridView
Type: Bug Report
0

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.

Declined
Last Updated: 05 Jun 2019 12:21 by ADMIN
Approved
Last Updated: 24 May 2019 04:56 by ADMIN
The decimal separator is removed when exporting with German culture on Windows Server 2012
Completed
Last Updated: 16 May 2019 08:57 by ADMIN
Release R1 2019
ADMIN
Created by: Dimitar
Comments: 0
Category: GridView
Type: Bug Report
1
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)

Workaround:

Hide the checkbox only.
Completed
Last Updated: 16 May 2019 08:56 by ADMIN
Release R1 2019
To reproduce:
1. Add a RadMultiColumnComboBox and populate it with data.
2. Set the DropDownStyle property of the control to DropDownList
3. Set the EditorControl.AllowSearchRow and the AutoSizeDropDownToBestFit properties to true .
4. When you open the drop down and try to use the search row (e.g. clicking over the arrow buttons), the drop down is closed.

Workaround: 
public partial class RadForm1 : Telerik.WinControls.UI.RadForm
{
    public RadForm1()
    {
        InitializeComponent();

        this.radMultiColumnComboBox1.EditorControl.AllowSearchRow = true;
        this.radMultiColumnComboBox1.DropDownStyle = Telerik.WinControls.RadDropDownStyle.DropDownList;
        this.radMultiColumnComboBox1.DropDownClosing += RadMultiColumnComboBox1_DropDownClosing;
    }

    private void RadMultiColumnComboBox1_DropDownClosing(object sender, RadPopupClosingEventArgs args)
    {
        Point position = this.radMultiColumnComboBox1.EditorControl.PointToClient(Cursor.Position);

        Telerik.WinControls.RadElement searchElement = this.radMultiColumnComboBox1.EditorControl.ElementTree.GetElementAtPoint(position);
        if (searchElement != null)
        {
            GridSearchCellElement parent = searchElement.FindAncestor<GridSearchCellElement>();
            if (parent != null)
            {
                args.Cancel = true;
            }
        }
    }
}
Declined
Last Updated: 16 May 2019 08:17 by ADMIN
1. Create a new project and setup hierarchy
2. Add a large number of rows as child rows to the last row at first level
3. Run the project and try to expand the last row
Declined
Last Updated: 16 May 2019 08:10 by ADMIN
- Create a new project containing RadGridView
- Build hierarchy with large text data in cells
- Set the AutoSizeRows property to true and AutoSizeColumnMode to Fill
- Run the project, scroll down and try to click on a cell
Completed
Last Updated: 16 May 2019 05:57 by ADMIN
Created by: Pieter
Comments: 1
Category: GridView
Type: Bug Report
0

Steps to reproduce:

  • Create a RadGridView
  • DataBind the grid to a DataView (it might also fail for other kinds of databinding or content)
  • For a column, call BestFit().
  • Remove that column from the grid.
  • Add the Grid to a parent form or control 
  • Make the form/control visible.

When the grid is loaded and displayed, a NullReferenceException will be thrown:


Message             : Object reference not set to an instance of an object.
Type                : System.NullReferenceException
Source              : Telerik.WinControls.GridView
Stack trace         : Telerik.WinControls.UI.BestFitHelper.SetColumnWidth(GridViewColumn column, Single desiredWidth)
                      Telerik.WinControls.UI.BestFitHelper.BestFitColumnCore(GridViewColumn column, BestFitColumnMode mode)
                      Telerik.WinControls.UI.BestFitHelper.ProcessRequests()
                      Telerik.WinControls.UI.RowsContainerElement.MeasureOverride(SizeF availableSize)
                      Telerik.WinControls.RadElement.MeasureCore(SizeF availableSize)
                      Telerik.WinControls.RadElement.Measure(SizeF availableSize)
                      Telerik.WinControls.UI.ScrollViewElement`1.MeasureViewElement(SizeF availableSize)
                      Telerik.WinControls.UI.ScrollViewElement`1.MeasureView(SizeF availableSize)
                      Telerik.WinControls.UI.ScrollViewElement`1.MeasureOverride(SizeF availableSize)
                      Telerik.WinControls.UI.GridTableElement.MeasureOverride(SizeF availableSize)
                      Telerik.WinControls.RadElement.MeasureCore(SizeF availableSize)
                      Telerik.WinControls.RadElement.Measure(SizeF availableSize)
                      Telerik.WinControls.Layouts.DockLayoutPanel.MeasureOverride(SizeF constraint)
                      Telerik.WinControls.RadElement.MeasureCore(SizeF availableSize)
                      Telerik.WinControls.RadElement.Measure(SizeF availableSize)
                      Telerik.WinControls.UI.LightVisualElement.MeasureElements(SizeF availableSize, SizeF clientSize, Padding borderThickness)
                      Telerik.WinControls.UI.LightVisualElement.MeasureOverride(SizeF availableSize)
                      Telerik.WinControls.RadElement.MeasureCore(SizeF availableSize)
                      Telerik.WinControls.RadElement.Measure(SizeF availableSize)
                      Telerik.WinControls.RootRadElement.MeasureOverride(SizeF availableSize)
                      Telerik.WinControls.RootRadElement.MeasureCore(SizeF availableSize)
                      Telerik.WinControls.RadElement.Measure(SizeF availableSize)
                      Telerik.WinControls.RadElementTree.PerformInnerLayout(Boolean performMeasure, Int32 x, Int32 y, Int32 width, Int32 height)
                      Telerik.WinControls.RadControl.OnLoad(Size desiredSize)
                      Telerik.WinControls.UI.RadGridView.OnLoad(Size desiredSize)
                      Telerik.WinControls.RadControl.LoadElementTree(Size desiredSize)
                      Telerik.WinControls.RadControl.OnCreateControl()
                      System.Windows.Forms.Control.CreateControl(Boolean fIgnoreVisible)
                      System.Windows.Forms.Control.CreateControl(Boolean fIgnoreVisible)
                      System.Windows.Forms.Control.CreateControl(Boolean fIgnoreVisible)
                      System.Windows.Forms.Control.CreateControl()
                      System.Windows.Forms.Control.SetVisibleCore(Boolean value)
                      Telerik.WinControls.UI.TabPanel.set_Visible(Boolean value)
                      Telerik.WinControls.UI.TabStripPanel.SetSelected(TabPanel tabPanel)
                      Telerik.WinControls.UI.TabStripPanel.UpdateTabSelection(Boolean updateFocus)
                      Telerik.WinControls.UI.Docking.DockTabStrip.UpdateTabSelection(Boolean updateFocus)
                      Telerik.WinControls.UI.Docking.ToolTabStrip.UpdateTabSelection(Boolean updateFocus)
                      Telerik.WinControls.UI.TabStripPanel.OnHandleCreated(EventArgs e)
                      System.Windows.Forms.Control.WmCreate(Message& m)
                      System.Windows.Forms.Control.WndProc(Message& m)
                      System.Windows.Forms.ScrollableControl.WndProc(Message& m)
                      Telerik.WinControls.RadControl.WndProc(Message& m)
                      Telerik.WinControls.UI.SplitPanel.WndProc(Message& m)
                      System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
                      System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
                      System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)


Approved
Last Updated: 16 May 2019 05:17 by ADMIN
To reproduce: please run the attached sample project and follow the steps illustrated in the attached gif file:

Scrolling to a newly added row does not work when inner templates are visible.

Add data to the inner templates of several rows near the bottom using the button.
Expand these inner templates so they are all visible.
Scroll back up to the top.
Add a new item to the outer grid normally.
The table will jump to where it things the new item is but will fall short, instead scrolling to a location in one of the inner templates.
Workaround:

        private void RadGridView1_UserAddedRow(object sender, GridViewRowEventArgs e)
        {
            foreach (GridViewRowInfo    row in this.radGridView1.Rows)
            {
                if (row.IsExpanded)
                {
                    row.IsExpanded = false;
                    row.IsExpanded = true;
                }
            }
        }
Approved
Last Updated: 16 May 2019 05:10 by ADMIN
How to reproduce:

1. Click DrugName Filter Icon.
2. Uncheck Combivent
3. OK
4. Click name Filter Icon
5. Uncheck Christoff
6. OK
7. Click DrugName Filter Icon
8. Uncheck Dilantin
9. OK

In this scenario the grid should display only 2 rows but it displays 3.

public partial class RadForm1 : Telerik.WinControls.UI.RadForm
{
    public List<Drug> DrugList { get; set; }

    public RadForm1()
    {
        InitializeComponent();
        DrugList = new List<Drug>();
        LoadDrugList();
        radGridView1.DataSource = DrugList;
        radGridView1.EnableFiltering = true;

        this.radGridView1.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill;
        this.radGridView1.MultiSelect = true;
    }

    protected override void OnLoad(EventArgs e)
    {
        base.OnLoad(e);

        radGridView1.MasterTemplate.ShowFilteringRow = false;
        radGridView1.MasterTemplate.ShowHeaderCellButtons = true;
    }

    void LoadDrugList()
    {
        DrugList.Add(new Drug { Dosage = 25, DrugName = "Indocin", Name = "David"});
        DrugList.Add(new Drug { Dosage = 50, DrugName = "Enebrel", Name = "Sam" });
        DrugList.Add(new Drug { Dosage = 10, DrugName = "Hydralazine", Name = "Christoff"});
        DrugList.Add(new Drug { Dosage = 21, DrugName = "Combivent", Name = "Janet"});
        DrugList.Add(new Drug { Dosage = 100, DrugName = "Dilantin", Name = "Melanie"});
    }

}

Workaround: use a custom filter popup
public partial class RadForm1 : Telerik.WinControls.UI.RadForm
{
    public List<Drug> DrugList { get; set; }

    public RadForm1()
    {
        InitializeComponent();
        DrugList = new List<Drug>();
        LoadDrugList();
        radGridView1.DataSource = DrugList;
        radGridView1.EnableFiltering = true;

        this.radGridView1.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill;
        this.radGridView1.MultiSelect = true;

        this.radGridView1.FilterPopupRequired += RadGridView1_FilterPopupRequired;
    }

    private void RadGridView1_FilterPopupRequired(object sender, FilterPopupRequiredEventArgs e)
    {
        e.FilterPopup = new CustomRadListFilterPopup(e.Column);
    }

    protected override void OnLoad(EventArgs e)
    {
        base.OnLoad(e);

        radGridView1.MasterTemplate.ShowFilteringRow = false;
        radGridView1.MasterTemplate.ShowHeaderCellButtons = true;
    }

    void LoadDrugList()
    {
        DrugList.Add(new Drug { Dosage = 25, DrugName = "Indocin", Name = "David"});
        DrugList.Add(new Drug { Dosage = 50, DrugName = "Enebrel", Name = "Sam" });
        DrugList.Add(new Drug { Dosage = 10, DrugName = "Hydralazine", Name = "Christoff"});
        DrugList.Add(new Drug { Dosage = 21, DrugName = "Combivent", Name = "Janet"});
        DrugList.Add(new Drug { Dosage = 100, DrugName = "Dilantin", Name = "Melanie"});
    }

}

public class CustomRadListFilterPopup : RadListFilterPopup
{
    public CustomRadListFilterPopup(GridViewDataColumn dataColumn) 
        : base(dataColumn)
    {
    }

    protected override void OnButtonOkClick(EventArgs e)
    {
        FilterMenuTreeItem treeMenuItem = this.Items.FirstOrDefault(i => i is FilterMenuTreeItem) as FilterMenuTreeItem;
        if (treeMenuItem == null)
        {
            base.OnButtonOkClick(e);
        }

        FilterMenuTreeElement listFilterElement = treeMenuItem.TreeElement;

        FilterOperator filterOperator = FilterOperator.IsEqualTo;

        switch (listFilterElement.SelectedMode)
        {
            case ListFilterSelectedMode.All:
                filterOperator = FilterOperator.None;
                break;
            case ListFilterSelectedMode.Null:
                filterOperator = FilterOperator.IsNull;
                break;
            case ListFilterSelectedMode.NotNull:
                filterOperator = FilterOperator.IsNotNull;
                break;
        }

        if (filterOperator != FilterOperator.IsEqualTo)
        {
            SetFilterOperator(filterOperator);
            this.ClosePopup(RadPopupCloseReason.CloseCalled);
        }
        else
        {
            CompositeFilterDescriptor compositeFilterDescriptor = new CompositeFilterDescriptor();
            compositeFilterDescriptor.PropertyName = this.DataColumn.Name;
            RadListFilterDistinctValuesTable distinctValues = this.GetDistinctValuesTable();
            string blanksKey = RadGridLocalizationProvider.CurrentProvider.GetLocalizedString(RadGridStringId.FilterMenuBlanks);
            bool blanks = listFilterElement.SelectedValues.Contains(blanksKey);
            compositeFilterDescriptor.LogicalOperator = FilterLogicalOperator.And;

            foreach (DictionaryEntry entry in distinctValues)
            {
                object key = entry.Key;

                if (string.IsNullOrEmpty(Convert.ToString(key)))
                {
                    key = blanksKey;
                }

                if (this.DataColumn is GridViewDateTimeColumn || this.DataColumn.DataType == typeof(DateTime) || this.DataColumn.DataType == typeof(DateTime?))
                {
                    DateTime dateTime;

                    if (DateTime.TryParse(key.ToString(), out dateTime))
                    {
                        object dataKey;
                        if (RadDataConverter.Instance.TryFormat(treeMenuItem.TreeElement.GroupedDateValues ? dateTime.Date : dateTime, typeof(string), this.DataColumn, out dataKey) == null)
                        {
                            key = dataKey;
                        }
                    }
                }

                if (!listFilterElement.SelectedValues.Contains(key))
                {
                    foreach (object value in (ArrayList)entry.Value)
                    {
                        FilterDescriptor descriptor;
                        if (value == DBNull.Value)
                        {
                            descriptor = new FilterDescriptor(this.DataColumn.Name, FilterOperator.IsNotEqualTo, null);
                        }
                        else if (this.DataColumn is GridViewDateTimeColumn || this.DataColumn.DataType == typeof(DateTime) || this.DataColumn.DataType == typeof(DateTime?))
                        {
                            descriptor = new DateFilterDescriptor(this.DataColumn.Name, FilterOperator.IsNotEqualTo, (DateTime?)value, false);
                        }
                        else
                        {
                            descriptor = new FilterDescriptor(this.DataColumn.Name, FilterOperator.IsNotEqualTo, value);
                        }

                        compositeFilterDescriptor.FilterDescriptors.Add(descriptor);
                    }
                }
            }

            if (this.DataColumn.FilterDescriptor != null)
            {
                CompositeFilterDescriptor compositeFilter = this.DataColumn.FilterDescriptor as CompositeFilterDescriptor;
                if (compositeFilter != null)
                {
                    foreach (var item in compositeFilter.FilterDescriptors)
                    {
                        if (listFilterElement.SelectedValues.Contains(item.Value))
                        {
                            continue;
                        }

                        FilterDescriptor descriptor = new FilterDescriptor(this.DataColumn.Name, FilterOperator.IsNotEqualTo, item.Value);
                        compositeFilterDescriptor.FilterDescriptors.Add(descriptor);
                    }
                }
                else if(!listFilterElement.SelectedValues.Contains(this.DataColumn.FilterDescriptor.Value))
                {
                    FilterDescriptor descriptor = new FilterDescriptor(this.DataColumn.Name, FilterOperator.IsNotEqualTo, this.DataColumn.FilterDescriptor.Value);
                    compositeFilterDescriptor.FilterDescriptors.Add(descriptor);
                }
            }
            this.FilterDescriptor = compositeFilterDescriptor;

            OnFilterConfirmed();
        }
    }
}
1 2 3 4 5 6