Opens an Edit Form for the focused row as a separate modal window.
The ShowPopupEditForm method displays an Edit Form as a separate modal window. This method is in effect if the GridOptionsBehavior.EditingMode property is set to a value that enables data editing via an Edit Form.
To display an Edit Form as an inline panel, call the GridView.ShowInplaceEditForm method. To display an Edit Form based on the Edit Form type specified in the GridOptionsBehavior.EditingMode property, call the GridView.ShowEditForm method.
If there is insufficient space in the GridView to display an Edit Form as an inline panel, it is forcibly displayed as a separate modal window.
If the GridOptionsBehavior.EditingMode property is set to GridEditingMode.Inplace or EditorShowMode.Default, the GridView.ShowInplaceEditForm, GridView.ShowPopupEditForm and GridView.ShowEditForm methods are not in effect.