 import spark.core.NavigationUnit;
 
 /**
- *  The base class for all layouts.
- * 
+ *  The LayoutBase class defines the base class for all Spark layouts.
  *  To create a custom layout that works with the Spark containers,
  *  you must extend <code>LayoutBase</code> or one of its subclasses.
  *

     }

    /**
     *  Returns the bounds of the target's scrollRect in layout coordinates.
     * 
     *  Layout methods should not get the target's scrollRect directly.
     * 
     *  @return The bounds of the target's scrollRect in layout coordinates, null
     *      if target or clipAndEnableScrolling is false. 

    [Inspectable(category="General")]
    
    /**
     *  @copy spark.core.IViewport#horizontalScrollPosition
     *
     *  @default 0
     *  
     *  @langversion 3.0
     *  @playerversion Flash 10
