topic Re: Identify features in NavMenu in ArcGIS API for Flex Questions

Identify features in NavMenu

ManuelFrias — Sat, 11 Dec 2021 15:06:15 GMT

Hi,

From the code Robert shared some time ago (http://gis.calhouncounty.org/SFVDemo) I am using the NavMenu which provides a shortcut to the navigation buttons.

I would like to add a new button which would mimic the IdentifyWidget. I added a new public static const to SiteContainer.mxml

  public static const WIDGET_SHOW_INFO:String    ="widgetShowInfo";

which will then call the public static const SHOW_INFOWINDOW in AppEvent.as

What I find tricky is how to make the infoData object.

var infoData:Object =
         *       {
         *          icon: icon,              //a Image object
         *          title: "a title string",
         *          content: "a string",
         *          link: "http://a.url.com",
         *          point: point,            //a Point object
         *          geometry: geom           //a Geometry object
         *       };

I looked at IdentifyWidget.mxml and thought I would try to replicate everything in there.

Is there an easier way or should I just go on?

Thanks,
Manolo

Re: Identify features in NavMenu

RobertScheitlin__GISP — Tue, 03 Aug 2010 11:22:53 GMT

Manolo,

I think that you are on the right path. Do you need any specific help?

Re: Identify features in NavMenu

ManuelFrias — Wed, 04 Aug 2010 12:33:06 GMT

Hi Robert,

yes, I would need some help (see attached file).

I think my problem is that when I define the variable map:

private var map:Map;

map doesn't get all the layers and I get the error "Cannot access a property or method of a null object reference" here:

map.addLayer(graphicsLayer);

If I initialize the variable (private var map:Map = new Map) the error disappears but map doesn't get any layers.

I've been looking what IdentifyWidget does and there there is no map definition since it gets it from BaseWidget.as. But how does it add all the layers? I don't find it.

Manolo

Re: Identify features in NavMenu

RobertScheitlin__GISP — Wed, 04 Aug 2010 12:43:23 GMT

Manolo,

If it is just the map then just do this

private var map:Map = SiteContainer.getInstance().controller.map;

Re: Identify features in NavMenu

ManuelFrias — Wed, 04 Aug 2010 12:53:38 GMT

Hi,

I still get "Cannot access a property or method of a null object reference." because map is null, I guess.

Manolo

Re: Identify features in NavMenu

RobertScheitlin__GISP — Wed, 04 Aug 2010 13:03:50 GMT

Manolo,

Attach your updated code so I can see what might be going wrong.

Re: Identify features in NavMenu

ManuelFrias — Wed, 04 Aug 2010 13:08:03 GMT

Hi Robert,

here you are the code with your suggestion.

Manolo

Re: Identify features in NavMenu

RobertScheitlin__GISP — Wed, 04 Aug 2010 15:02:41 GMT

Manolo,

Here you go the issue was that the mapmanager had not created the map yet when we were calling for it.

Re: Identify features in NavMenu

ManuelFrias — Thu, 05 Aug 2010 10:19:59 GMT

Thanks Robert!

I could hardly have figured out myself.

I wonder if you know where I can get the visible layers? I tried to get the LayerIds property of identifyParams and then assign the visibleLayers

identifyParams.layerIds = dynamicLayer.visibleLayers.source;

but that doesn't work (see attached code). I did something similar in my IdentifyWirdget.mxml and worked out fine.

Manolo

Re: Identify features in NavMenu

RobertScheitlin__GISP — Sat, 11 Dec 2021 15:06:17 GMT

Manolo,

Try this:

private function identifyFeatures():void
   {
    var identifyParams:IdentifyParameters = new IdentifyParameters();
    identifyParams.returnGeometry = false;
    identifyParams.tolerance = identifyTolerance;
    identifyParams.geometry = identifyPoint;
    identifyParams.width = map.width;
    identifyParams.height = map.height;
    identifyParams.layerOption = IdentifyParameters.LAYER_OPTION_VISIBLE;
    identifyParams.mapExtent = map.extent;
    
    for (var i:Number = map.layerIds.length -1; i >= 0; i--)
    {
     identifyParams.layerIds = null;
     var layer:Layer = map.getLayer(map.layerIds);
     var url:String;
     if (layer.visible)
     {
      if (layer is ArcGISDynamicMapServiceLayer)
      {
       var dynamicLayer:ArcGISDynamicMapServiceLayer = layer as ArcGISDynamicMapServiceLayer;
       url = dynamicLayer.url;
       if(identifyLayerOption == "visible")
                     {
                      identifyParams.layerIds = dynamicLayer.visibleLayers.source;
                      identifyParams.layerOption = "all";
                      if(dynamicLayer.visible == false)
                       url="";
                     }
       
      }
      else if (layer is ArcGISTiledMapServiceLayer)
      {
       var tiledLayer:ArcGISTiledMapServiceLayer = layer as ArcGISTiledMapServiceLayer;
                     url = tiledLayer.url;
                     if(identifyLayerOption == "visible")
                     {
                      if(tiledLayer.visible == false)
                       url="";
                     }
      }
      if (url)
      {
       var identifyTask:IdentifyTask = new IdentifyTask(url);
       identifyTask.addEventListener(IdentifyEvent.IDENTIFY_COMPLETE, onResult);
       identifyTask.addEventListener(FaultEvent.FAULT, onFault);
       identifyTask.execute(identifyParams);
      }
     }
    }
   }

Re: Identify features in NavMenu

ManuelFrias — Thu, 05 Aug 2010 12:51:43 GMT

Hi Robert,

Almost! That code identified the visible layer but it returned an error "invalid layer specified" six times (I have seven map services).

Then I added the following line:

if (identifyLayerOption == "visible" && dynamicLayer.visibleLayers.length > 0)

and I don't get the error but now it identifies all layers in the one map service. The service where there is one visible layer 😞

Manolo

Re: Identify features in NavMenu

ManuelFrias — Fri, 06 Aug 2010 08:02:47 GMT

I got it,

I removed the "invalid layer specified" error by commenting out Alert.show in function onFault. I don't know why this error appeared but it might be because I had modified the MapMapneger to show the cursor when clinking on a button.

Then it identified also my tiled layers which I didn't want to. I solved it by assigning "" to url when a tiledLayer was identified.

I attached the final mxml for those who want to experiment/improve/use it.

Thank you Robert for pointing me in the right direction.

And now, how do I assign your points? Don't tell me is not ready yet in this new forum.

Manolo

Re: Identify features in NavMenu

RobertScheitlin__GISP — Fri, 06 Aug 2010 11:38:12 GMT

Manolo,

Yep, they don't have it worked out yet so just remember to come back later when they do.