The MultiRow control supports the allowAddNew and allowDelete properties provided by the FlexGrid control.
Setting the allowAddNew property to true causes the grid to display a set of 'new row template' rows at the bottom of the grid. When user starts editing a cell in the new row template, a new item is added to the source collection. When user finishes editing the new item by moving the selection to another row or the focus to another control, the new item is committed.
Setting the allowDelete property to true causes the grid to monitor key presses and to delete the current row if user presses the 'Delete' key while an entire row is selected.