public/javascripts/yui/container/container.js
function() {
            if (this.mask) {
                var panelZ = Dom.getStyle(this.element, "zIndex");
                if (!YAHOO.lang.isUndefined(panelZ) && !isNaN(panelZ)) {
                    Dom.setStyle(this.mask, "zIndex", panelZ - 1);
                }
            }
        }
function() {
            if (this.mask) {
                var panelZ = Dom.getStyle(this.element, "zIndex");
                if (!YAHOO.lang.isUndefined(panelZ) && !isNaN(panelZ)) {
                    Dom.setStyle(this.mask, "zIndex", panelZ - 1);
                }
            }
        }
function ( ) { if ( this . mask ) { var panelZ = Dom . getStyle ( this . element , "zIndex" ) ; if ( ! YAHOO . lang . isUndefined ( panelZ ) && ! isNaN ( panelZ ) ) { Dom . setStyle ( this . mask , "zIndex" , panelZ - 1 ) ; } } }
Sets the zindex of the mask, if it exists, based on the zindex of
the Panel element. The zindex of the mask is set to be one less
than the Panel element's zindex.

<p>NOTE: This method will not bump up the zindex of the Panel
to ensure that the mask has a non-negative zindex. If you require the
mask zindex to be 0 or higher, the zindex of the Panel
should be set to a value higher than 0, before this method is called.
</p>
@method stackMask
Sets the zindex of the mask if it exists based on the zindex of the Panel element . The zindex of the mask is set to be one less than the Panel element s zindex .