onItemRollOver - getting the Error #1009:

DorothyMortenson — Wed, 06 Oct 2010 17:35:52 GMT

Hello,
I am migrating my application from 1.3 to 2.0; and from Flex 3 to Flash Builder 4.

My application:
1) Displays a map with dam locations
2) allows the user to pick a point and distance for a buffer
3) shows the results of which dams are within the buffer in a datagrid.

My revised application works, up until the user rolls over anything in the datagrid.
Then I get the error:
TypeError: Error #1009: Cannot access a property or method of a null object reference.
at dams_v2/findGraphicByAttribute()
at dams_v2/onItemRollOver()
at dams_v2/__dg_itemRollOver()
...

It would seem that something is out of order, but I don't know what it is.

Thanks for any help.
Dorothy

/* ------------------------------------------------
On Item Rollover
---------------------------------------------- */
private function onItemRollOver( event:ListEvent ) : void
{
var gr:Graphic = findGraphicByAttribute(event.itemRenderer.data)
Alert.show("glow set up here")

var glow:Glow = new Glow(gr);
Alert.show("glow set up here2")
glow.duration = 1000 ;
glow.alphaFrom = 1 ;
glow.alphaTo = 0 ;
glow.blurXFrom = 20 ;
glow.blurXTo = 0 ;
glow.blurYFrom = 30 ;
glow.blurYTo = 0 ;
glow.strength = 40;
glow.color = 0xFFFF33;

glow.play();
}

/* ------------------------------------------------
On Item Click
---------------------------------------------- */
private function onItemClick(event:ListEvent) : void
{
var graphic:Geometry = findGraphicByAttribute(event.itemRenderer.data).geometry;
var gr: Graphic = findGraphicByAttribute(event.itemRenderer.data)
var graphicExtent:Extent;
var grPt:MapPoint;
var testIndex:String = event.columnIndex.toString();

if (testIndex == "5")
{
   //Center & Zoom to selected feature
   grPt = MapPoint(graphic);
   Map.centerAt(grPt);
   Map.scale = 10000;
}

//Temporarily highlight selected graphic symbol
gr.symbol = highlightedSymbol;
}

/* ------------------------------------------------
Find Graphics by Attribute
---------------------------------------------- */
public function findGraphicByAttribute(attributes:Object):Graphic
{
for each(var graphic:Graphic in graphicsLayer.graphicProvider)
{
      trace("att:" + graphic.attributes["damname"] );
      if (graphic.attributes["damname"] == attributes["damname"])
      {
          return graphic;
      }
}
return null;
}

Re: onItemRollOver - getting the Error #1009:

DasaPaddock — Wed, 06 Oct 2010 17:46:20 GMT

What's the code on line 284?

Re: onItemRollOver - getting the Error #1009:

DorothyMortenson — Fri, 08 Oct 2010 14:13:36 GMT

if (graphic.attributes["damname"] == attributes["damname"])

within the function:
/* ------------------------------------------------
Find Graphics by Attribute
---------------------------------------------- */
public function findGraphicByAttribute(attributes:Object):Graphic
{
Alert.show("made it to start findGraphicByAttribute.")
for each(var graphic:Graphic in graphicsLayer.graphicProvider)
{
     // trace("att:" + graphic.attributes["damname"] );
      if (graphic.attributes["damname"] == attributes["damname"])
      {
          return graphic;
      }
}
return null;
}

Re: onItemRollOver - getting the Error #1009:

DorothyMortenson — Fri, 08 Oct 2010 17:04:54 GMT

I changed the code to be:

if (graphic.attributes == attributes)

And it is now working.

topic onItemRollOver - getting the Error #1009: in ArcGIS API for Flex Questions

onItemRollOver - getting the Error #1009:

Re: onItemRollOver - getting the Error #1009:

Re: onItemRollOver - getting the Error #1009:

Re: onItemRollOver - getting the Error #1009: