         // Justify
         switch(justifyColumns)
         {
-            case "gapSize":
+            case TileJustifyColumns.GAPSIZE:
                 _horizontalGap = justifyByGapSize(width, _columnWidth, _horizontalGap, _columnCount);
             break;
-            case "columnSize":
+            case TileJustifyColumns.COLUMNSIZE:
                 _columnWidth = justifyByElementSize(width, _columnWidth, _horizontalGap, _columnCount);
             break;
         }
 
         switch(justifyRows)
         {
-            case "gapSize":
+            case TileJustifyRows.GAPSIZE:
                 _verticalGap = justifyByGapSize(height, _rowHeight, _verticalGap, _rowCount);
             break;
-            case "rowSize":
+            case TileJustifyRows.ROWSIZE:
                 _rowHeight = justifyByElementSize(height, _rowHeight, _verticalGap, _rowCount);
             break;
         }

    //  justifyRows
    //----------------------------------

    // TODO EGeorgie: add enum class
    private var _justifyRows:String = "none";

    [Inspectable(category="General")]

    /**
     *  Specifies how to justify the fully visible rows to the container height.
     *  Supported values are "none", "gapSize", "rowSize".
     *
     *  <p>When set to "none" - turns column justification off, there may
     *  be partially visible rows or whitespace between the last row and
     *  the bottom edge of the container.  This is the default value.</p>
     *
     *  <p>When set to "gapSize" - the <code>verticalGap</code> actual value will increase so that
     *  the last fully visible row bottom edge aligns with the container's bottom edge.
     *  In case there is only a single fully visible row, the <code>verticalGap</code> actual value
     *  will increase so that it pushes any partially visible row just beyond the bottom edge

            childHeight = element.getPreferredBoundsHeight();

        // Enforce min and max limits
        var maxChildWidth:Number = Math.min(element.getMaxBoundsWidth(), cellWidth);
        var maxChildHeight:Number = Math.min(element.getMaxBoundsHeight(), cellHeight);
        // Make sure we enforce element's minimum last, since it has the highest priority
        childWidth = Math.max(element.getMinBoundsWidth(), Math.min(maxChildWidth, childWidth));
        childHeight = Math.max(element.getMinBoundsHeight(), Math.min(maxChildHeight, childHeight));
