public void updateVisiblityValue(int referenceIndex){
  mCachedVisibleArea=mLayoutTab.computeVisibleArea();
  mCachedIndexDistance=Math.abs(mIndex - referenceIndex);
  mOrderSortingValue=computeOrderSortingValue(mCachedIndexDistance,mCacheStackVisibility);
  mVisiblitySortingValue=computeVisibilitySortingValue(mCachedVisibleArea,mOrderSortingValue,mCacheStackVisibility);
}

public void updateVisiblityValue ( int referenceIndex ) { mCachedVisibleArea = mLayoutTab . computeVisibleArea ( ) ; mCachedIndexDistance = Math . abs ( mIndex - referenceIndex ) ; mOrderSortingValue = computeOrderSortingValue ( mCachedIndexDistance , mCacheStackVisibility ) ; mVisiblitySortingValue = computeVisibilitySortingValue ( mCachedVisibleArea , mOrderSortingValue , mCacheStackVisibility ) ; }
updates the cached visible area value to be used to sort tabs by visibility .
