      */
     private function measuredSizePreliminaryHandler(event:FlexEvent):void
     {
+        if (!inUpdateDisplayListVirtual)
+            return;
+
         event.target.addEventListener(FlexEvent.MEASURED_SIZE_FINAL, measuredSizeFinalHandler, false, 0, true);
 		if (!notFinalTargets)
 			notFinalTargets = [];

            return;
        
        if (_target)
            _target.removeEventListener(FlexEvent.MEASURED_SIZE_PRELIMINARY, measuredSizePreliminaryHandler);
        _target = value;
        super.target = value;
        if (value)
            value.addEventListener(FlexEvent.MEASURED_SIZE_PRELIMINARY, measuredSizePreliminaryHandler, false, 0, true);
    }
    
    //--------------------------------------------------------------------------
    //
    //  Methods

     */
    override public function estimateSizesOfElements():void
    {
        if (llv && target.estimatedWidth != lastEstimatedWidth && llv.minorSizeBasedOnLayoutSize)
        {
            llv.minorSize = 0;
            llv.minMinorSize = 0;
        }
        lastEstimatedWidth = target.estimatedWidth;
        
        var size:SizesAndLimit = new SizesAndLimit();
        var spaceToDistribute:Number = !isNaN(target.explicitHeight) ? target.explicitHeight : target.estimatedHeight;
