Joining graphics into one graphic

BrendanLee — Tue, 25 May 2010 19:56:54 GMT

I'm trying to union or append graphics into one graphic. Can it be done? Or should I try a different way?

I want to allow the user to draw a polygon on the screen and select the parcels that intersect the polygon. Then I want to take all the parcels and buffer them.

Here's my code:

/* Required with a DrawEnd event.*/
    private function onDrawEnd(event:DrawEvent):void
    {
  var graphic:Graphic = event.graphic;

  // adding graphic to the graphics layer
  myGraphicsLayer.add(graphic);
    
  var geometryPolygon:Polygon = graphic.geometry as Polygon;
  myMap.centerAt(geometryPolygon.extent.center);
                
   // select parcels contained or crossed by drawn polygon
  findParcels(graphic);             
 }
            
 private function findParcels(graphic:Graphic):void
 {          
  // clear the graphics layer
  myGraphicsLayer.clear();
                
  // Create query to select parcels that intersect drawn shape                      
  var parcelQuery : Query = new Query();
  parcelQuery.returnGeometry = true;
  parcelQuery.geometry = graphic.geometry;
  parcelQuery.spatialRelationship = "esriSpatialRelIntersects";
  parcelQuery.outSpatialReference = myMap.spatialReference;
                         
  parcelQueryTask.execute( parcelQuery, new AsyncResponder( onParcelResult, onParcelFault ));
                
  function onParcelResult( featureSet : FeatureSet, token : Object = null ) : void
  {             
   if (featureSet.features.length != 0)                     
   {
    var unionExtent : Extent;
    var myFirstGraphic : Graphic = featureSet.features[0];
    unionExtent = Polygon(myFirstGraphic.geometry).extent;

    for each (var myGraphic : Graphic in featureSet.features)
    {
                 myGraphic.symbol = (sfs);
                 myGraphicsLayer.add(myGraphic);

                                // THINK I NEED TO ADD SOMETHING HERE TO APPEND ALL GRAPHICS IN FEATURESET INTO ONE GRAPHIC THAT CAN BE USED BY BUFFER FUNCTION.
                    // Adds parcel number and address as tool tip
                    myGraphic.toolTip = "Parcel: " + myGraphic.attributes.PARCEL.toString()
                     + "\nAddress: " + myGraphic.attributes.STRNO + " " 
                        + myGraphic.attributes.STRDIR + " "
                        + myGraphic.attributes.STRNAME + " "
                        + myGraphic.attributes.STRTYPE;
                    
                    // Expand extent                           
     unionExtent = unionExtent.union(Polygon(myGraphic.geometry).extent );
    }

    // Zoom map out a bit
    myMap.extent = unionExtent.expand(6); 
                
   }
   else
   {
    Alert.show("Error selecting parcels");
   }
  }  
  function onParcelFault( info : Object, token : Object = null ) : void
  {
   Alert.show( info.toString() );
  }
 }

 private function bufferFeature():void
 {
  var bufferParameters:BufferParameters = new BufferParameters();
        bufferParameters.features = [graphicParcels];
  bufferParameters.distances = [ 500 ]; 
  bufferParameters.unit = BufferParameters.UNIT_FOOT;
  bufferParameters.bufferSpatialReference = new SpatialReference(32007); 

  myGeometryService.addEventListener(GeometryServiceEvent.BUFFER_COMPLETE, bufferCompleteHandler1);
  myGeometryService.buffer(bufferParameters);

  function bufferCompleteHandler1(event:GeometryServiceEvent):void
  {
   for each (var graphic:Graphic in event.graphics)
   {
    graphic.symbol = sfs;
    graphic.toolTip = "Buffered Stuff";
    myGraphicsLayer.add(graphic);
   }
            myGeometryService.removeEventListener(GeometryServiceEvent.BUFFER_COMPLETE, bufferCompleteHandler1);
  }
 }

Re: Joining graphics into one graphic

BrendanLee — Tue, 25 May 2010 21:42:18 GMT

I've added the following code:

graphicParcels = myGraphicsLayer.graphicProvider[myGraphicsLayer.numGraphics-1];

But it seems like it doesn't contain all the graphics. If I remove the -1 nothing happens.
I think I'm close...Help!

Re: Joining graphics into one graphic

DasaPaddock — Tue, 25 May 2010 22:00:19 GMT

The graphicProvider is an ArrayCollection so you can turn it into an Array like this:

graphicParcels = ArrayCollection(myGraphicsLayer.graphicProvider).toArray();

http://resources.esri.com/help/9.3/arcgisserver/apis/flex/apiref/com/esri/ags/layers/GraphicsLayer.html#graphicProvider

Re: Joining graphics into one graphic

BrendanLee — Tue, 25 May 2010 22:07:58 GMT

The graphicProvider is an ArrayCollection so you can turn it into an Array like this:
graphicParcels = ArrayCollection(myGraphicsLayer.graphicProvider).toArray();
http://resources.esri.com/help/9.3/arcgisserver/apis/flex/apiref/com/esri/ags/layers/GraphicsLayer.html#graphicProvider

That worked! Thanks.

topic Joining graphics into one graphic in ArcGIS API for Flex Questions

Joining graphics into one graphic

Re: Joining graphics into one graphic

Re: Joining graphics into one graphic

Re: Joining graphics into one graphic