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Raster identify (pixel value) with viewer for flex

MartynSmith

I'm trying to create a simple flex viewer app that will display a popup or hovertip containing a raster pixel value. I have searched the forums and haven't found any way to do this with the ArcGIS viewer for Flex. I was thinking perhaps it would be possible using the geoprocessing widget and a geoprocessing service (ie. extract values from points).

If it can't be done with the viewer, is this possible using the ArcGIS API for flex? I am running ArcGIS Server 9.3.

Any help would be appreciated.

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LeonardoAraújo

This was also my mistake. Initially I had only one image service published and was trying to identify the pixels of this service. Then I saw that I had to publish a map service for the raster files, but had left the service image in main config file and was using the map service only in Identify widget. Now set up the map service in the main config file and it worked perfectly.

Thanks a lot.

rzufelt

Sorry Robert,

Brain fart on my end.

Turns out I had identifylayeroption=visible, but was fogetting to change the elevation layer in my main config to the 10.1 version.

Now that it is actually "visible" in my map, it appears to be honoring it, even with onlythese=true and is accepting "Pixel Value" as the field.

R_

Also, this version plays nicely with the ElevationProfileWidget. Still have to close it to get the draw tool back to Identify, but no longer get the null value errors if I try to use identify after running the profile widget.

Funny how it works the way you tell it to 🙂

rzufelt

{"results":[{"layerId":0,"layerName":"Elevation","value":"152.869995","displayFieldName":"","attributes":{"Class value":"1","Pixel Value":"152.869995"},"geometryType":"esriGeometryPoint","geometry":{"x":574551.584524985,"y":147006.98256411,"spatialReference":{"wkid":32149}}}]}

Is this the string you were looking for?

I've tried value, and Pixel Value, and pixel value so far with no luck.

R_

rscheitlin

Rhett,

Catch the http traffic in Fiddler and see what server 10.1 is returning for the raster field name when you identify that raster with the only these as false.

rzufelt

Well, that could be my issue then, as my raster data is floating point, so has no attribute table and thus no Fields tab.

Weird that it works with the 10.0 service, but not 10.1....

However, both services report the same thing if I identify with ArcMap.

[ATTACH=CONFIG]22853[/ATTACH]

R_

untitled1.jpg

rscheitlin

Rhett,

This is what I have working for 10.1 Raster:

        <layer>
            <name>Soils</name>
            <id>0</id>
            <url>http://gislap183/arcgis/rest/services/RasterIdentify/MapServer</url&gt;
            <fields>
                <field name="MUSYM" />
            </fields>
            <links>
                <link includeinresults="false" field="" alias=""
                    tooltip="">
                    <linkprefix />
                    <linksuffix />
                    <iconfield />
                    <iconprefix />
                    <iconsuffix />
                </link>
            </links>
            <zoomscale>15000</zoomscale>
            <forcescale>true</forcescale>
        </layer>

Where if I look in my mxd that has the raster and go to it's layer properties and then to the fields tab it lists:
[TABLE="class: grid"]Name
Type
Length
Percision
Scale
Value
Long
4
0
0
Count
Double
8
0
0
MUSYM
String
8
0
0

[/TABLE]

rzufelt

More on this. It seems that both AGS 10 and 10.1 will identify, however, I don't know how to get it to honor the fields tag in 10.1.

with 10.05, it honors my field tag, and will work with onlythese="true", but since I don't have the proper syntax for 10.1, it will only work if I have it set to onlythese="false", but get no field formatting.

R_

rzufelt

I'm trying to figure this out also. I have it working in 3.1.2f, but that one will give me null value errors if I have run the ElevationProfileWidget previously so I tried to upgrade, but can't figure out how to get 3.1.4 to identify raster values from AGS 10.05.

However, it seems to work with AGS 10.1. Will this only support rasters on 10.1, or is it something I'm doing differently?

Thanks,

R_

Noticed that even using AGS 10.1, I can only get raster values if I select All Layers and must have onlythese="false". If I pick the actuall elevation data, I get no results found.

Not sure, but might be related to the fields tag as I can't get it to display anything if I try to make it follow them.

This used to work in older version:

    <field name="Pixel Value" alias="NAVD88 (m)"  numberformat="2|,|." />

but doesn't anymore. Odd, as if I let it identify it will all layers, it shows Pixel Value and Class Value, but can't figure out how to honor it in the fields tag.

Seems the only way I can get it to work is onlythese="false", then exclude all the other layer/sublayers in the map.

LeonardoAraújo

All,

Configuring the identification of raster layers is now supported in the 3.1.2 version of the Identify Widget.

Hi Robert,

Could you tell me how do I configure the identification of raster layers to get the pixel value? I have not seen anything about this in the IdentifyWidget.xml file.

I'm already using the version 3.1.4 of the widget.

Thanks.

rscheitlin

All,

Configuring the identification of raster layers is now supported in the 3.1.2 version of the Identify Widget.

RobertMarin

Martyn,
I saw this thread and have trying to get the identify widget to return a pixel value from a raster (a DEM), but no luck. Vector layers work just fine. (Being a newbie, I am using flexbuilder 3.1, not the API).

I built a raster attribute table (integer) and created an elevation field, published the DEM as a map service and loaded it into the builder, but the widget doesn't seem to recognize the raster field. I notice in the REST services that my DEM layer doesn't show a display field (even though one is selected in the source) .mxd. What step(s) am I missing here?
Rob

MartynSmith

Robert-

Just upgraded to Identify Widget 2.5 and was very pleased to see you implemented all of my little tweaks! this is great. Appreciate your time on this.

Martyn

rscheitlin

Martyn,

Sure if you read the documentation you will see that there is a config setting in the xml for this, keepidentifyactive.

MartynSmith

Perfect Robert! your help is truly appreciated. Well on my way.

Robert, one more question. Is there an easy way to just make the "Identify by point" active and keep it active so that as long as you have the identify widget window open, you can keep clicking points? In other words, not deactivate the Identify tool after a result is returned.

MartynSmith

Perfect Robert! your help is truly appreciated. Well on my way.

rscheitlin

Martyn,

1) In the IdentifyWidget.mxml make these changes:

<mx:Image id="iDrawLine"
                          name="{DrawTool.POLYLINE}"
                          width="40" height="40"
                          buttonMode="true"
                          click="{activateIdentifyTool(event)}"
                          rollOut="iconRollOutHandler(event)"
                          rollOver="iconRollOverHandler(event)"
                          source="assets/images/i_draw_line.png"
                          toolTip="{lineLabel}"
                          useHandCursor="true"
                          visible="false"/>
                <mx:Image id="iDrawExt"
                          name="{DrawTool.EXTENT}"
                          width="40" height="40"
                          buttonMode="true"
                          click="{activateIdentifyTool(event)}"
                          rollOut="iconRollOutHandler(event)"
                          rollOver="iconRollOverHandler(event)"
                          source="assets/images/i_draw_rect.png"
                          toolTip="{rectLabel}"
                          useHandCursor="true"
                          visible="false"/>
                <mx:Image id="iDrawPoly"
                          name="{DrawTool.POLYGON}"
                          width="40" height="40"
                          buttonMode="true"
                          click="{activateIdentifyTool(event)}"
                          rollOut="iconRollOutHandler(event)"
                          rollOver="iconRollOverHandler(event)"
                          source="assets/images/i_draw_poly.png"
                          toolTip="{polyLabel}"
                          useHandCursor="true"
                          visible="false"/>

2) Now I have to assume that you want feet added to all the results and you will not be using the identify widget for any other purpose than to identify your raster layer and it returns one field that you want feet appended to...

            private function onResult(event:IdentifyEvent):void                
            {   
//My stuff
                var identifyResults:Array = event.identifyResults;
                var cFormater:NumberFormatter = new NumberFormatter
                cFormater.precision = "2";
                cFormater.rounding = "nearest";
                cFormater.decimalSeparatorFrom = "."
                cFormater.decimalSeparatorTo = "."
                cFormater.useThousandsSeparator = "false";
//End my stuff
                
                if(!identifyArrayCollection)
                    identifyArrayCollection = new ArrayCollection();
                for each (var identifyResult:IdentifyResult in identifyResults)
                {
                    var title:String = identifyResult.layerName;
                    var obj:Object = identifyResult.feature.attributes;
                    //var content:String = 'X & Y: ' + cFormater.format((identifyResult.feature.geometry as MapPoint).x) + ", " + cFormater.format((identifyResult.feature.geometry as MapPoint).y) + "\n";
                    var content:String = "";
                    var fld:String;
                    var value:String;
                    var link:String = "";
                    var linkicon:String = "";
                    var identFields:String = "";
                    var identLinkPre:String = "";
                    var identLinkField:String = "";
                    var identLinkSuffix:String = "";
                    var identLinkIcon:String = "";
                    var identLinkIconPre:String = "";
                    var identLinkIconSuffix:String = "";
                    var identZoom:Number = 0;
                    var identForceScale:Boolean = false;
                    var idResult:IdResult = new IdResult();
                    
                    for(var i:int=0; i<configIdentFields.length; i++)
                    {
                        if (identifyResult.layerName == configIdentFields.label)
                        {
                            identLinkField = configIdentFields.linkfield;
                            identFields = configIdentFields.fields;
                            identLinkPre = configIdentFields.linkpre;
                            identLinkSuffix = configIdentFields.linksuffix;
                            identLinkIconPre = configIdentFields.linkiconpre;
                            identLinkIcon = configIdentFields.linkicon;
                            identLinkIconSuffix = configIdentFields.linkiconsuffix;
                            identZoom = configIdentFields.zoomscale;
                            identForceScale = configIdentFields.forcescale;
                        }
                    }
                    
                    if(identFields != "") {
                        var fldArr:Array = StringUtil.trimArrayElements(identFields,",").split(",");
                        for (var f:Number = 0; f < fldArr.length; f++) {
                            try{                                   
                                value = obj[fldArr] ? String(obj[fldArr]) : "";
                            } catch (error: Error){
                                value = "";
                            }
                            value += " Feet";
                           ...........................................................................................................

MartynSmith

Martyn,

1) Currently No, not without changing the code.
2) Currently No, not without changing the code.
3) Aliases are pulled from the featureclass or map document automatically when using the Identify task.

If you have the ability to change the code and recompile then just let me know and I will point you to where changes need to be made.

Robert I do have the ability, have flash builder 4.5.. have the viewer source, and have your widget source. Not an expert, but I worked with the viewer source to some degree. Any help you could give me would be great.

rscheitlin

Martyn,

1) Currently No, not without changing the code.
2) Currently No, not without changing the code.
3) Aliases are pulled from the featureclass or map document automatically when using the Identify task.

If you have the ability to change the code and recompile then just let me know and I will point you to where changes need to be made.

MartynSmith

Martyn,

No that is definitely a bad assumption. The identify widget is capable of because it sends the request to the server and works server side with the identify request. A popup is usually working client side with the featurelayers graphics or a query and or select request (which does go back to the server, but is not going to return a pixel value).

Thanks Robert, I'm a flex and AGS newb. Just stumbling around for now. Your widget is definitely doing the job for me. If you can answer a couple more questions from me regarding your widget that would be great:

(1) Is it possible to remove the line, rectangle and area selection options as choices since only the "Identify by point" applies for a raster? (2) Is it possible to add a suffix to a field after the identify result, such as a "feet"? (3) Is there any way to use aliases for fields? That would really help to clean up the identify results window

Thanks again

rzufelt

Was afraid you were going to say that.

can't build attribute table for 32 bit float. can't lose my decimals here, so guess I'm going to see Pixel value.

Thanks for the update,

R_

MartynSmith

Thanks Martyn,

I got the identity tool to give me the values. However, I noticed that you have it saying "Depth", wheras I just get "Pixel value". Was wondering how you got the "Depth" to show instead.

Thanks,

R_

In my map document, I did a "build raster attribute table" for the raster, then created a new field called "DEPTH" to which I then just copied the raster default "VALUE" field into. Hope that helps.

rscheitlin

Martyn,

No that is definitely a bad assumption. The identify widget is capable of because it sends the request to the server and works server side with the identify request. A popup is usually working client side with the featurelayers graphics or a query and or select request (which does go back to the server, but is not going to return a pixel value).

rzufelt

Thanks Martyn,

I got the identity tool to give me the values. However, I noticed that you have it saying "Depth", wheras I just get "Pixel value". Was wondering how you got the "Depth" to show instead.

Thanks,

R_

MartynSmith

I actually did manage to get a raster pixel value with Robert Scheitlin's identify widget (see attachment). This isn't a documented feature of the widget but it does in fact work getting a pixel value from a raster. Its not perfect, and doesn't allow for too much customization of the Identify widget window, however.

What I'd like to get working is the new for Viewer for Flex PopUp widget to get a raster pixel value. Since it works with the identify widget, I'm assuming its possible with a 9.3 Map Service REST endpoint.

Can anyone help me get this set up?

ScreenShot004.png

rzufelt

Was wondering if you ever found a solution for this?

Piece of cake using the Web ADF maps with the identify tool, but have not figured out a way with Flex/Flash.

Of course, need to figure this out for a Mapservice, as I don't have ImageServer.

Thanks,

R_

Professional ESRI beta tester (aka paying customer)

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