Arcgis api for Flex 实现线要素的图形与标题的显示

var graphic:Graphic=event.graphic as Graphic;
var layer:FeatureLayer=graphic.graphicsLayer as FeatureLayer;
if(layer.layerDetails.name=="Road")
{
var polyline:Polyline=graphic.geometry as Polyline;
var linePaths:Array=polyline.paths;
var linePonits:Array=linePaths[0] as Array;
var linePoint:MapPoint=linePonits[Math.round(linePonits.length/2)];
var pointGraphic:Graphic=new Graphic();
pointGraphic.geometry=linePoint as Geometry;
pointGraphic.symbol=roadTextSymbol;

pointGraphic.attributes=graphic.attributes;
roadSymbolGraphicLayer.add(pointGraphic);
roadSymbolGraphicLayer.refresh();
map.addLayer(roadSymbolGraphicLayer);
}