The events are fired in the following order: UserAddingRow, EditorRequired, UserAddedRow eventfired when the new is pinned at the bottom and TAB key is processed.

Workaround:

public class FixGridNewRowBehavior : GridNewRowBehavior
{
    protected override bool ProcessTabKey(System.Windows.Forms.KeyEventArgs keys)
        {
            bool isInEditMode = this.EditorManager.IsInEditMode;
 
 
            if (isInEditMode)
            {
                IGridNavigator navigator = GridViewElement.Navigator;
 
                bool isLeftNavigation = navigator.IsFirstColumn(GridViewElement.CurrentColumn) && keys.Shift;
                bool isRightNavigation = navigator.IsLastColumn(GridViewElement.CurrentColumn) && !keys.Shift;
 
                if (isLeftNavigation || isRightNavigation)
                {
                    this.GridViewElement.EndEdit();
                }
 
                if (isLeftNavigation)
                {
                    navigator.SelectLastColumn();
                }
                else if (isRightNavigation)
                {
                    navigator.SelectFirstColumn();
                }
 
                if (isLeftNavigation || isRightNavigation)
                {
                    GridViewElement.BeginEdit();
                    return true;
                }
            }
 
            return base.ProcessTabKey(keys);
        }
} 

BaseGridBehavior gridBehavior = this.radGridView1.GridBehavior as BaseGridBehavior;
gridBehavior.UnregisterBehavior(typeof(GridViewNewRowInfo));
gridBehavior.RegisterBehavior(typeof(GridViewNewRowInfo), new FixGridNewRowBehavior());

StackOverFlow exception when the user sorts a GridView control.  The exception occurs in the CellValueNeeded method when accessing e.RowIndex.  The GridView is in VirtualMode.  The error doesn't occur during the initial load of the data.

When exporting to HTML or PDF image columns should be exported properly.

1. Create a new project with RadGridView and setup 2 level hierarchy.
2. Add a checkbox column at the second level and set its pinned state to Left.
3. Run the application.
4. Expand the first row and click on the checkbox. Be sure that RadGridView contains enough columns in its child view to show horizontal scrollbar.

Workaround:  create a custom view definition
public class CustomTableViewDefinition : TableViewDefinition
{
    public override IRowView CreateViewUIElement(GridViewInfo viewInfo)
    {
        CustomTableElement table = new CustomTableElement();
        return table;
    }
}
 
public class CustomTableElement : GridTableElement
{
    protected override Type ThemeEffectiveType
    {
        get
        {
            return typeof(GridTableElement);
        }
    }
 
    public override bool EnsureCellVisible(GridViewRowInfo rowInfo, GridViewColumn column)
    {
        if (column.IsPinned)
        {
            return true;
        }
        return base.EnsureCellVisible(rowInfo, column);
    }
}

Set the view definition to the child template by using the ViewDefinition property

this.gridViewDemoData.Templates[0].ViewDefinition = new CustomTableViewDefinition();

How to handle this case:

Subscribe to the CellValidating event and add logic for validation. For example:

If e.Value Is Nothing Then
    e.Cancel = True
End If

Additionally you can handle the DataError event to handle cases where users are trying to submit invalid data through the grid to its data source.

Finally, you can subscribe to the ContextMenuOpening event where to hide the "Clear value" item from context menu with following code snippet:

For i As Integer = 0 To e.ContextMenu.Items.Count - 1
    If e.ContextMenu.Items(i).Text = "Clear Value" Then
        e.ContextMenu.Items(i).Visibility = Telerik.WinControls.ElementVisibility.Collapsed
    End If
Next

If one exports a grid with AutoSizeRows set to true the rows that are not visible or have not been scrolled to in the grid will be exported with wrong (very small) height.

To reproduce: 
 void radGridView1_ViewCellFormatting(object sender, Telerik.WinControls.UI.CellFormattingEventArgs e)
        {
            GridFilterCellElement filterCell = e.CellElement as GridFilterCellElement;
            if (filterCell != null)
     

When exporting to excel the exporter exports null values as empty strings instead of empty excel cells.

Filtering of enum data type throws exception.

Selecting datasource throws exception, then crashes VS

Exception is thrown when keyboard navigation is used and RadGridView is grouped. Steps to reproduce:
1. Apply Office 2010 Silver theme to RadGridView.
2. Group the grid by two columns
3. Set AutoSizeRows to true.
3. Edit a decimal column
4. Navigate at right column
5. Exception is thrown.

ADD. RadGridView - one should be able to show the header row on each page exported in PDF

Add Page format functionality (like header, footer, page number) when you export a RadGridView to pdf similar to RadPrintDocument.
http://www.telerik.com/help/winforms/tpf-printing-support-radprintdocument-header-and-footer.html

Allow getting all child rows of GridViewGroupRowInfo before filtering and sorting operation to be applied.

Gridview contains one image column and one text column. It is supposed that the data in the gridview is sorted by the text column. EnableSorting is enabled for the whole gridview. The image column has AllowSort disabled and SortOrder set to None whereas the text column has the SortOrder set to Ascending. However, if the grid is populated with data it is primarily sorted by the image column. 
This problem is illustrated in the attached project. I've added three rows with data and would expect the grid be sorted as "A", "B", "C", whereas the resulting order is "B", "C", "A" due to the image in the row which contains the "A".

RadExpressionEditorForm to not close when the created expression is not valid.

Self-reference expander cell is reused inappropriately when horizontal scrolling is performed.

The sort check box, the expression editor button and the text box text should be localized

Workaround:  this.radGridView1.XmlSerializationInfo.SerializationMetadata.Add(typeof(GridViewSummaryItem), 
                "AggregateExpression", DesignerSerializationVisibilityAttribute.Content);

Summary rows evaluation does not support custom aggregation expressions as Count(IIF(Result='Pass' ,1, Null))