     //---------------------------------- 
     
     /**
-     *  Defines the layout of the navigationGroup.
+     *  Defines the layout of the components contained in 
+     *  the <code>navigationGroup</code> skin part.
      *
      *  @default HorizontalLayout
+     *
+     *  @see #navigationContent
      *  
      *  @langversion 3.0
      *  @playerversion Flash 10

[SkinState("titleWithActionAndNavigation")]

/**
 *  ActionBar with titleContent in place of titleDisplay
 *  
 *  @langversion 3.0
 *  @playerversion Flash 10

    [ArrayElementType("mx.core.IVisualElement")]
    
    /**
     *  The components that appear in the title area of the control. 
     *  These components appear in the <code>titleGroup</code> 
     *  skin part of the ActionBar control.
     *
     *  <p>The location and appearance of the <code>titleGroup</code> 
     *  skin part is determined by the skin.
     *  The default ActionBarSkin class defines the <code>titleGroup</code>
     *  to appear in the center of the ActionBar,
     *  using the space remaining between <code>navigationGroup</code> 
     *  and <code>actionGroup</code> skin parts.</p>
     * 
     *  <p>If <code>titleContent</code> is null, the
     *  <code>titleDisplay</code> skin part, if present, is displayed 
     *  in place of the <code>titleGroup</code> skin part.</p> 
     * 
     *  <p>Create a custom skin to change the default location and appearance of
     *  the <code>titleGroup</code> skin part.</p>
     *  
     *  @default null
     *
     *  @see spark.skins.mobile.ActionBarSkin
     *  @see #title
     *  @see #titleLayout
     * 
     *  @langversion 3.0
     *  @playerversion Flash 10
