topic Re: Buffer query result polygon in ArcGIS JavaScript Maps SDK Questions

Buffer query result polygon

DonCaviness — Wed, 01 Aug 2012 16:05:59 GMT

I am trying to buffer the result of a query which is a polygon. I have tried several different approaches but my code always fails when calling the geometry service's buffer function. Once I buffer the selected polygon (the query result) I'm going to use the geometry of the buffer to do a spatial query. Can anyone see what is the issue with my code? Thanks, Don.

function performParcelSearch(){
    var parcelVal = $("#inputParcel").val();
    var bufferDist = $("#inputBuffer").val();
    var symbol = new esri.symbol.SimpleFillSymbol(esri.symbol.SimpleFillSymbol.STYLE_SOLID, new esri.symbol.SimpleLineSymbol(esri.symbol.SimpleLineSymbol.STYLE_DASHDOT, new dojo.Color([255, 0, 0]), 2), new dojo.Color([255, 255, 0, 0.25]));
    var queryTask = new esri.tasks.QueryTask(searchLayer);
    if (!parcelVal) {
        alert("Please enter a parcel number.");
    }
    else {
        var qryExp = "parcel_f = '" + parcelVal + "'";
        //initialize query
        var parcelQuery = new esri.tasks.Query();
        parcelQuery.returnGeometry = true;
        parcelQuery.outFields = ["*"];
        parcelQuery.where = qryExp;
        
        //execute query
        queryTask.execute(parcelQuery, function showResults(featureSet){
            //remove all graphics on the maps graphics layer
            map.graphics.clear();
            var features = featureSet.features;
            
            //QueryTask returns a featureSet.  Loop through features in the featureSet and add them to the map.
            dojo.forEach(features, function(feature){
                var graphic = feature;
                graphic.setSymbol(symbol);
                console.log("BB");
                
                //Add graphic to the map graphics layer.
                var featureextent = graphic.geometry.getExtent();
                map.setExtent(featureextent, true);
                map.graphics.add(graphic);
                
                /*------------------------------------*/
                // Performs Buffer Search
                /*------------------------------------*/
                if (bufferDist > 0) {
                
                    $("#exportDiv").show("slow");
                    $("#bufferResultsDiv").show("slow");
                    var params = new esri.tasks.BufferParameters();
                    params.distances = bufferDist;
                    params.bufferSpatialReference = map.spatialReference;
                    params.outSpatialReference = map.spatialReference;
                    params.unit = esri.tasks.GeometryService.UNIT_FOOT;
                    params.geometries = feature.geometry;
                    
     geometryService.buffer(params, showBuffer);
                }
            });
        });
    }
}

Re: Buffer query result polygon

StephenLead — Sat, 11 Dec 2021 10:43:57 GMT

my code always fails when calling the geometry service's buffer function.
geometryService.buffer(params, showBuffer);

I haven't stepped through your code, but are you sure that there's a showBuffer function (I can't see it in your extract)? This is what will run once the buffer operation is complete.

If so, can you put a breakpoint on the first line of showBuffer and let us know what you see? According to the help file you should receive back an array of geometries.

Steve

Re: Buffer query result polygon

DonCaviness — Thu, 02 Aug 2012 15:22:06 GMT

Thanks Steve. However I only posted a snippet of my code and I didn't include the showBuffer function, that is why you don't see it. With that being said, the function is never getting called. In fact, the geometry service is not getting called at all.

geometryService.buffer(params, showBuffer);

I have used firebug and fiddler but the code is never calling the service. I am beginning to think there is a bug in the JS API. The generic error that I get is always with the api. I think that when I get the geometry from the query featureSet, the geometry isn't formatted correctly for the geometry service. Of course, I could be missing something all together. I welcome any suggestions.

Re: Buffer query result polygon

ReneRubalcava — Thu, 02 Aug 2012 15:37:48 GMT

Try parseInt on your bufferDist value.
This line is returning your value as a string.

var bufferDist = $("#inputBuffer").val();

Re: Buffer query result polygon

DonCaviness — Thu, 02 Aug 2012 15:58:41 GMT

I tried your suggestion Rene but that didn't seem to have an effect on anything. The geometry service still isn't being called. From looking at the code, do you any reason why what I'm trying to do wouldn't work? I have seen the Esri samples that pass an user drawn geometry to the geometry service to perform a buffer. I just don't see why what I'm trying to do won't work. I have tried everything I know to try. I have done this exact thing using the flex api but I just can't get it to work with the js api. What am I missing?

Re: Buffer query result polygon

ReneRubalcava — Thu, 02 Aug 2012 16:03:44 GMT

Without running it the only thing that stands out as a possibility is this line.

params.geometries = feature.geometry;

I think it needs to be passed as an array.

params.geometries = [ feature.geometry ];

That's how the ref shows it.
http://help.arcgis.com/EN/webapi/javascript/arcgis/help/jsapi/bufferparameters.htm#geometries

Other than that, not too sure.

Re: Buffer query result polygon

DonCaviness — Thu, 02 Aug 2012 16:20:20 GMT

I have tried that before but I just tried it again and it still had no effect. The geometry service still isn't getting called. I have attached the error I'm getting in firebug.

[ATTACH=CONFIG]16601[/ATTACH]

Re: Buffer query result polygon

ReneRubalcava — Thu, 02 Aug 2012 16:45:12 GMT

This is v3.0 right? I heard someone comment that if your dojo.Config has { async: true }, that the geometry service may not work properly. I was never able to confirm it, but I just remembered right now.

Re: Buffer query result polygon

DonCaviness — Thu, 02 Aug 2012 17:05:45 GMT

I do not have async: true in the dojo.config. I am using version 3.0 but I was having the same issues with version 2.8. This has just completely confused/frustrated me as to why it isn't working. It seems so simple what I'm trying to accomplish.

Re: Buffer query result polygon

DonCaviness — Tue, 07 Aug 2012 18:16:41 GMT

I've tested this in versions 2.8, 3.0 and 3.1 of the JS api and the geometry service still isn't getting called. Does anyone have any ideas on how to get this to work?

Re: Buffer query result polygon

JohnGravois — Tue, 07 Aug 2012 20:52:16 GMT

Don,

are you referencing a proxy in your application? The Javascript API requires that you use one to pass complex geometries in a request to a geometry operation.

http://help.arcgis.com/en/webapi/javascript/arcgis/help/jshelp/ags_proxy.htm

Re: Buffer query result polygon

DonCaviness — Tue, 07 Aug 2012 21:02:22 GMT

I am aware of the use of a proxy page while using complex geometries. That actually bit me a year or so ago on another project. I am however using a proxy in this case as well. I would think it might have something to do with a proxy if the geometry service itself was actually getting called and nothing worked, however that isn't the case here. The code is failing before the call is made to the geometry service.

Re: Buffer query result polygon

StephenLead — Tue, 07 Aug 2012 21:57:43 GMT

Can you post a link to your site?

Re: Buffer query result polygon

DonCaviness — Wed, 08 Aug 2012 15:15:04 GMT

Steve, unfortunately the site I am working on is not public as of now. All I can do is post the snippet of the code that I'm having an issue with, which I posted here originally.

Re: Buffer query result polygon

ReddaiahPurma — Sat, 18 Aug 2012 06:29:51 GMT

May b this will help you...

Buffer along Selected Feature with two distances.................. Code in attachment........

<div id="FeatureIntersectBufferdialog" title="Query Intersect Buffer" style="display: none;">
        <div id="FeatureIntersectd">
        <table cellspacing="0" cellpadding="3" border="0" width="100%" height="100%">
          <tr>
           <td width="180px;">
            <span style="font-weight:bold;" >Select Main Service </span>
           </td>
           <td width="200px;">
             <select id="FIBService" style="width:180px;" onchange="FIBMainDrpServiceChange();" ></select>
           </td>
          </tr>
          <tr>
           <td width="180px;">
           <span style="font-weight:bold;" >Select Main Layer </span>
           </td>
           <td width="200px;">
           <select id="FeatureIntersectdrp" style="width:180px;"></select>
           </td>
          </tr>
          <tr>
           <td width="180px;">
            <span style="font-weight:bold;" >Buffer Distances </span>
           </td>
           <td width="200px;" style="padding:3px;">
           <input type="text" id="distanceIntersectFeatureBuffer" size="5" value="10" style="width:80px;" />
              <input type="text" id="distanceIntersectFeatureBuffer0" size="5" value="100" style="width:80px;"/><br/>
              <select id="unitIntersectFeatureBuffer" style="width:180px;">
                  <option value="UNIT_STATUTE_MILE">Miles</option>
                  <option value="UNIT_FOOT">Feet</option>
                  <option value="UNIT_KILOMETER">Kilometers</option>
                  <option value="UNIT_METER">Meters</option>
                  <option value="UNIT_NAUTICAL_MILE">Nautical Miles</option>
                  <option value="UNIT_US_NAUTICAL_MILE">US Nautical Miles</option>
                  <option value="UNIT_DEGREE">Degrees</option>
              </select>

           </td>
          </tr>
          <tr>
           <td width="180px;">
            <span style="font-weight:bold;" >Select Intersection Service </span>
           </td>
           <td width="200px;">
             <select id="FIBInterService" style="width:180px;"></select>
           </td>
          </tr>
          <tr>
           <td width="180px;">

           </td>
           <td width="200px;">
            <button onclick="clrGraphics(map);initFuntionalityFeatureIntersecttBuffer(map);" dojotype="dijit.form.Button">
                  Submit</button>
               <button onclick="clrGraphics(map);" dojotype="dijit.form.Button">
                   Clear</button><br />
                   <span style="font-style:italic;" >Click on Map after Submit...</span>
           </td>
          </tr>

          <tr>
           <td width="180px;">
            <span style="font-weight:bold;" >select Affected Layer</span>
           </td>
           <td width="200px;">
            <select id="FeatureIntersectdrpAffectedLayer" style="width:180px;"></select>
            <br />
                <button onclick="clrGraphics(map);initGetFeatureFeatureIntersectBuffer(map);" dojotype="dijit.form.Button">
                   Get Features</button>
           </td>
          </tr>
          <tr>
           <td colspan="2" ><br /><span style="font-style:italic;" id="messagesFeatureIntersect"></span>
           </td>
          </tr>

    </table><div id="FeatureIntersectPost" dojotype="dijit.layout.ContentPane" title="Feature Buffer Results" ></div>
        </div>
    </div>

Re: Buffer query result polygon

DonCaviness — Mon, 20 Aug 2012 15:25:28 GMT

Thank you all for your help. However the issue I was having was a simple one and it was caused by me over looking the details. I needed to pass the distance to the geometry service as an array. Once I did this it worked beautifully.