ThemeResolutionService.ApplicationThemeName = "Windows11"

        Dim UserGroup As New DescriptionTextListDataItem
        With UserGroup
            .Text = "Admins"
            '.Font = New Font("Microsoft Sans Serif", 9.75, FontStyle.Bold)
            .DescriptionText = "System Administrations Group"
        End With
        Me.RadListControl1.Items.Add(UserGroup)
        Me.RadListControl1.ItemHeight = 50

************** Exception Text **************
System.NullReferenceException: Object reference not set to an instance of an object.
   at Telerik.WinControls.UI.RadTimePickerElement.set_Value(Object value) in C:\Work\Development\RadControls\RadControlsUI\RadTimePicker\Elements\RadTimePickerElement.cs:line 594
   at Telerik.WinControls.UI.RadTimePickerContentElement.element_Click(Object sender, EventArgs e) in C:\Work\Development\RadControls\RadControlsUI\RadTimePicker\Elements\ContentPart\RadTimePickerContentElement.cs:line 585
   at Telerik.WinControls.RadElement.OnClick(EventArgs e) in C:\Work\Development\RadControls\RadControl\TPF\Element\RadElement.cs:line 5094
   at Telerik.WinControls.RadElement.DoClick(EventArgs e) in C:\Work\Development\RadControls\RadControl\TPF\Element\RadElement.cs:line 5158
   at Telerik.WinControls.RadElement.RaiseBubbleEvent(RadElement sender, RoutedEventArgs args) in C:\Work\Development\RadControls\RadControl\TPF\Element\RadElement.cs:line 4272
   at Telerik.WinControls.RadItem.RaiseBubbleEvent(RadElement sender, RoutedEventArgs args) in C:\Work\Development\RadControls\RadControl\TPF\Element\RadItem.cs:line 779
   at Telerik.WinControls.RadElement.RaiseRoutedEvent(RadElement sender, RoutedEventArgs args) in C:\Work\Development\RadControls\RadControl\TPF\Element\RadElement.cs:line 4179
   at Telerik.WinControls.RadElement.DoMouseUp(MouseEventArgs e) in C:\Work\Development\RadControls\RadControl\TPF\Element\RadElement.cs:line 5271
   at Telerik.WinControls.RadElement.CallDoMouseUp(MouseEventArgs e) in C:\Work\Development\RadControls\RadControl\TPF\Element\RadElement.cs:line 5493
   at Telerik.WinControls.ComponentInputBehavior.OnMouseUp(MouseEventArgs e) in C:\Work\Development\RadControls\RadControl\TPF\Control\ComponentInputBehavior.cs:line 75
   at Telerik.WinControls.RadControl.OnMouseUp(MouseEventArgs e) in C:\Work\Development\RadControls\RadControl\TPF\Control\RadControl.cs:line 1206
   at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
   at Telerik.WinControls.RadControl.WndProc(Message& m) in C:\Work\Development\RadControls\RadControl\TPF\Control\RadControl.cs:line 1554
   at Telerik.WinControls.UI.RadPopupControlBase.WndProc(Message& m) in C:\Work\Development\RadControls\RadControlsUI\GenericPopup\RadPopupControlBase.cs:line 795
   at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

        Timer t = new Timer();

        private void RadTimePicker1_ValueChanged(object sender, EventArgs e)
        {
            if (radTimePicker1.Value == null) return;

            var timeval = ((DateTime)radTimePicker1.Value).TimeOfDay;

            if (timeval == TimeSpan.Zero)
            {
                t = new Timer();
                t.Interval = 500;
                t.Tick += T_Tick; t.Start();
            }
        }

        private void T_Tick(object sender, EventArgs e)
        {
            t.Stop();
            this.radTimePicker1.ValueChanged -= RadTimePicker1_ValueChanged;
            this.radTimePicker1.Value = null;
            this.radTimePicker1.ValueChanged += RadTimePicker1_ValueChanged;
        }

    Sub New()

        InitializeComponent()
        Me.RadSpinEditor1.EnableNullValueInput = True
        Me.RadSpinEditor1.NullableValue = Nothing

        Console.WriteLine("Value " & Me.RadSpinEditor1.Value & " END")
        Console.WriteLine("NullableValue " & Me.RadSpinEditor1.NullableValue & " END")
    End Sub

    Private Sub RadSpinEditor1_NullableValueChanged(sender As Object, e As EventArgs) Handles RadSpinEditor1.NullableValueChanged
        Console.WriteLine("NullableValueChanged " & Me.RadSpinEditor1.NullableValue & " END")
    End Sub

        Me.RadFilterView1.FilterViewElement.LoadCategoriesAsync = False
        Me.RadGridView1.DataSource = Me.ProductsBindingSource
        Me.RadGridView1.EnableFiltering = True
        Me.RadGridView1.ShowFilteringRow = False


        AddHandler Me.RadFilterView1.FilterChanged, AddressOf Me.RadFilterView1_FilterChanged
        AddHandler Me.RadFilterView1.FilterViewElement.CategoryCreating, AddressOf Me.FilterViewElement_CategoryCreating
        AddHandler Me.RadFilterView1.FilterViewElement.CategoryCreated, AddressOf Me.FilterViewElement_CategoryCreated

        Me.RadFilterView1.AssociatedControl = Me.RadGridView1

       
        Dim filter As New FilterDescriptor With {
            .PropertyName = "ProductID",
            .Operator = FilterOperator.IsLessThanOrEqualTo,
            .Value = 5,
            .IsFilterEditor = True
        }

        Dim filter2 As New FilterDescriptor With {
            .PropertyName = "CategoryID",
            .Operator = FilterOperator.IsLessThanOrEqualTo,
            .Value = 4,
            .IsFilterEditor = True
        }
        Me.RadFilterView1.FilterDescriptors.AddRange(filter, filter2)

en Telerik.WinControls.UI.BestFitHelper.SetColumnWidth(GridViewColumn column, Single desiredWidth)
   en Telerik.WinControls.UI.BestFitHelper.BestFitColumnCore(GridViewColumn column, BestFitColumnMode mode)
   en Telerik.WinControls.UI.BestFitHelper.ProcessRequests()
   en Telerik.WinControls.UI.GridTableElement.UpdateAll()
   en Telerik.WinControls.UI.GridTableElement.UpdateViewCore(Object sender, DataViewChangedEventArgs args)
   en Telerik.WinControls.UI.GridTableElement.UpdateView(Object sender, DataViewChangedEventArgs args)
   en Telerik.WinControls.UI.GridTableElement.ProcessTemplateEvent(GridViewEvent eventData)
   en Telerik.WinControls.UI.GridTableElement.Telerik.WinControls.UI.IGridViewEventListener.ProcessEvent(GridViewEvent eventData)
   en Telerik.WinControls.UI.GridViewEventProcessEntity.ProcessCollection(GridViewEvent gridEvent, PriorityWeakReferenceList list, GridEventProcessMode processMode)
   en Telerik.WinControls.UI.GridViewEventProcessEntity.ProcessEvent(GridViewEvent gridEvent)
   en Telerik.WinControls.UI.GridViewSynchronizationService.NotifyListeners(GridViewEvent gridEvent)
   en Telerik.WinControls.UI.GridViewSynchronizationService.FlushEvents()
   en Telerik.WinControls.UI.GridViewSynchronizationService.DispatchEvent(GridViewEvent gridEvent)
   en Telerik.WinControls.UI.GridViewSynchronizationService.DispatchEvent(GridViewTemplate template, GridViewEvent eventData, Boolean postUI)
   en Telerik.WinControls.UI.GridViewTemplate.DispatchEvent(GridViewEvent gridEvent, Boolean postUI)
   en Telerik.WinControls.UI.GridViewTemplate.DispatchDataViewChangedEvent(Object sender, DataViewChangedEventArgs args)
   en Telerik.WinControls.UI.GridViewTemplate.OnViewChanged(Object sender, DataViewChangedEventArgs e)
   en Telerik.WinControls.UI.MasterGridViewTemplate.OnViewChanged(Object sender, DataViewChangedEventArgs e)
   en Telerik.WinControls.UI.GridViewTemplate.CollectionView_CollectionChanged(Object sender, NotifyCollectionChangedEventArgs e)
   en Telerik.WinControls.Data.RadCollectionView`1.OnCollectionChanged(NotifyCollectionChangedEventArgs args)
   en Telerik.WinControls.Data.RadDataView`1.RebuildData(Boolean notify)
   en Telerik.WinControls.Data.RadDataView`1.RefreshOverride()
   en Telerik.WinControls.Data.RadDataView`1.ProcessCollectionChanged(NotifyCollectionChangedEventArgs args)
   en Telerik.WinControls.Data.RadCollectionView`1.source_CollectionChanged(Object sender, NotifyCollectionChangedEventArgs e)
   en Telerik.WinControls.Data.NotifyCollectionChangedEventHandler.Invoke(Object sender, NotifyCollectionChangedEventArgs e)
   en Telerik.WinControls.Data.RadListSource`1.OnCollectionChanged(NotifyCollectionChangedEventArgs e)
   en Telerik.WinControls.Data.RadListSource`1.EndUpdate(Boolean notifyUpdates)
   en Telerik.WinControls.Data.RadListSource`1.Initialize()
   en Telerik.WinControls.Data.RadListSource`1.Bind(Object dataSource, String dataMember)
   en Telerik.WinControls.Data.RadListSource`1.set_DataSource(Object value)
   en Telerik.WinControls.UI.GridViewTemplate.set_DataSource(Object value)
   en Telerik.WinControls.UI.RadGridView.set_DataSource(Object value)

internal bool IsSelected(GridViewRowInfo row, GridViewColumn column) => row != null && column is GridViewDataColumn && this.hashtable.Contains((object) this.GetHashCodeString(row, column));

 private string GetHashCodeString(GridViewRowInfo row, GridViewColumn column)
    {
      int hashCode = row.GetHashCode();
      string str1 = hashCode.ToString();
      hashCode = column.GetHashCode();
      string str2 = hashCode.ToString();
      return str1 + str2;
    }

 private string GetHashCodeString(GridViewRowInfo row, GridViewColumn column)
    {
      int hashCode = row.GetHashCode();
      string str1 = hashCode.ToString();
      hashCode = column.GetHashCode();
      string str2 = hashCode.ToString();
      return str1 + "_" + str2;
    }