      * 
      *  @param rowIndex The 0-based row index of the cell that changed, or -1.
      *
-     *  @param column Index The 0-based column index of the cell that changed or -1.
+     *  @param columnIndex The 0-based column index of the cell that changed or -1.
      *  
      *  @langversion 3.0
      *  @playerversion Flash 10

        _itemRenderer = value;
        
        itemRendererChanged = true;
        invalidateSize();
        invalidateDisplayList();
        

    public function invalidateCell(rowIndex:int, columnIndex:int):void
    {
        if (!dataProvider)
			return;
		
		const dataProviderLength:int = dataProvider.length;
		if (rowIndex >= dataProvider.length)
			return;
		
		if (!isCellVisible(rowIndex, columnIndex))
			return;

        if (invalidateDisplayListFlag || invalidateSizeFlag)
            return;        
		
		if ((rowIndex >= 0) && (columnIndex >= 0))
		{
            gridLayout.invalidateCell(rowIndex, columnIndex);
		}
        else if (rowIndex >= 0)  // invalidate a row
        {
            const visibleColumnIndices:Vector.<int> = getVisibleColumnIndices();
            for each (var visibleColumnIndex:int in visibleColumnIndices)
            {
                gridLayout.invalidateCell(rowIndex, visibleColumnIndex);
                
                // If invalidating the cell caused the entire grid to be invalid, punt 
                if (invalidateDisplayListFlag || invalidateSizeFlag)
                    break;                
            }
        }
		else if (columnIndex >= 0)  // invalidate a column
		{
			const visibleRowIndices:Vector.<int> = getVisibleRowIndices();
			for each (var visibleRowIndex:int in visibleRowIndices)
			{
				// If there are any padding rows, skip them.
				if (visibleRowIndex >= dataProviderLength)
					break;
                
                gridLayout.invalidateCell(visibleRowIndex, columnIndex);

                // If invalidating the cell caused the entire grid to be invalid, punt 
                if (invalidateDisplayListFlag || invalidateSizeFlag)
                    break;
			}
		}
    }
    
    /**
