Thank you for writing.
You can access the date time editor in the CellEditorInitialized event and there you can enable its time picker:
sender, GridViewCellEventArgs e)
RadDateTimeEditor editor = e.ActiveEditor
RadDateTimeEditorElement element = (RadDateTimeEditorElement)editor.EditorElement;
element.CalendarSize = new Size(400,250);
More about the editors in RadGridView is available here: http://www.telerik.com/help/winforms/gridview-editors.html
I hope that you find this information useful. Should you have any other questions, do not hesitate to contact us.
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