RouteArrowOptions  
    Options for determining the appearance of maneuver arrow(s)
Parameters
arrowColor 
the color of the arrow shaft
arrowCasingColor  
the color of the arrow shaft border
arrowHeadIcon  
the drawable to represent the arrow head
arrowHeadIconCasing   
the drawable to represent the arrow head border
aboveLayerId  
indicates the maneuver arrow map layers appear above this layer on the map
tolerance
the tolerance value used when configuring the underlying map source
arrowShaftScaleExpression   
an Expression governing the scaling of the maneuver arrow shaft
arrowShaftCasingScaleExpression    
an Expression governing the scaling of the maneuver arrow shaft casing
arrowHeadScaleExpression   
an Expression governing the scaling of the maneuver arrow head
arrowHeadCasingScaleExpression    
an Expression governing the scaling of the maneuver arrow head casing