topic Re: Print Widget and Renderers with Functions in ArcGIS JavaScript Maps SDK Questions

Print Widget and Renderers with Functions

DanielTrone — Fri, 10 May 2013 16:54:18 GMT

I am using the print widget and have noticed an unusual issue.

When I use a function-formula in the renderer instead of a simple variable, the legend does not display normally, but instead displays only the symbols used for that area and the label 'Override' (see attachment). Is this a bug? (Also see code snippet below).

Secondly, also when I am using a function formula in the renderer, and when I use a defaultSymbol instead of setting the first parameter of ClassBreaksRenderer to false, the print process will fail.

Thirdly, when I use a renderer with a simple variable, and no default symbol, it works, but my transparency is always opaque. (At least in the first situation, with the Override labels, the transparency is correct).

<CODE>
if (themevar === 'PCT_OTH_R') {
   renderer = new esri.renderer.ClassBreaksRenderer(false, function (graphic) {
    return ((graphic.attributes.OTHER_NH / graphic.attributes.POP0711) * 100);
   });
   renderer.addBreak({
    minValue: 0,
    maxValue: 2,
    symbol: new esri.symbol.SimpleFillSymbol().setColor(new dojo.Color([239, 237, 245, 0.5])),
    label: "< 2%"
   });
   renderer.addBreak({
    minValue: 2,
    maxValue: 5,
    symbol: new esri.symbol.SimpleFillSymbol().setColor(new dojo.Color([188, 189, 220, 0.5])),
    label: "2% to 5%"
   });
   renderer.addBreak({
    minValue: 5,
    maxValue: Infinity,
    symbol: new esri.symbol.SimpleFillSymbol().setColor(new dojo.Color([117, 107, 177, 0.5])),
    label: "> 5%"
   });
   $('#titleleg').html('PCT Other');
}
</CODE>

Here is a link to the working application to see the print behavior in action.

http://dola.colorado.gov/gis-cms/sites/default/files/html/acs0711_11.html

And here is the fiddle (sorry its so long, but still 1/5 size of original project).
http://jsfiddle.net/DanielTrone/e2yse/

Re: Print Widget and Renderers with Functions

JohnGravois — Fri, 10 May 2013 18:04:45 GMT

based on my reading of the export webmap spec and a look at your own request, this is happening because you are currently passing a collection of graphics whose symbology is defined feature by feature, rather than in a class breaks renderer (defined within drawingInfo).

if you're able to further whittle down your fiddle to use a single layer (and actually give an opportunity to redefine symbology based on population and race), it would be easier to see what your options are.

Re: Print Widget and Renderers with Functions

DanielTrone — Fri, 10 May 2013 19:06:06 GMT

Thanks for taking the time to look at this problem.

I have significantly cleaned up the fiddle down to only the essential elements. http://jsfiddle.net/DanielTrone/e2yse/1/

Note how the legend works for 'Median HH Income' (simple variable instead of a function, no default symbol) and how it doesnt work at all for 'Per Capita Income' (uses a default symbol).

Also note how 'Age less than 18' has the Override label text (uses a function instead of a simple variable).

And note how the transparency is wrong on 'Median HH Income', but correct on 'Age less than 18'.

Re: Print Widget and Renderers with Functions

JohnGravois — Sat, 11 Dec 2021 23:58:49 GMT

i took your code and wrote up a really simplified sample where the symbology is actually passed to ArcGIS Server with a class breaks renderer defined for the layer (instead of defining symbols feature by feature).

the only difference between my app and yours is that I am referencing a hardcoded featureLayer and you are pulling your layer from a webmap.

i didn't realize till just now, but your own web_map_json defines the layer as a "featureCollection". i wonder why the hosted feature service ends up acting like a graphics layer?

"id" : "TractACSv4_4105",
   "opacity" : 1,
   "minScale" : 0,
   "maxScale" : 0,
   "featureCollection" : {
    "layers" : [{
      "layerDefinition" : {
       "name" : "TractACSv4",

Re: Print Widget and Renderers with Functions

DanielTrone — Mon, 13 May 2013 14:44:52 GMT

I'm not sure I understand what's wrong (regarding feature collection vs graphics layer) and what I can do to fix it.

Also, have you noticed that if you replace 'false' with 'defaultSymbol' on the class breaks renderer, the Print operation fails? (might that have something to do with the first problem?)

Re: Print Widget and Renderers with Functions

JohnGravois — Tue, 14 May 2013 21:09:27 GMT

i took the time to adapt my simplified sample to pull your webmap and im still not seeing the same behavior as in your own application

http://jsfiddle.net/jagravois/A6cuH/1/

with regard to passing a default symbol in a class breaks renderer in the webmap json, i think im seeing the same thing you are, and will work on putting together something even more straightforward to show the problem.

Re: Print Widget and Renderers with Functions

DanielTrone — Wed, 15 May 2013 20:27:40 GMT

MED_AGE may not be the best example to use, because it is used directly in the Class Breaks Renderer. (though note how the transparency is messed up anyway).

I took your fiddle and changed the Variable to AGE65PLUS, and used a calculated value in as the second parameter in the Class Breaks Renderer. You should be able to see the legend problem here. (Legend says Override 1, Override 2. Transparency is correct, though).

http://jsfiddle.net/DanielTrone/xrGPh/2/

Re: Print Widget and Renderers with Functions

JohnGravois — Sat, 11 Dec 2021 23:58:52 GMT

thanks for pointing that out. now i FINALLY understand what is going on.

in this situation you are calculating a new value to use for your class breaks renderer on the fly without designating a new attribute column to store the value you calculated. (i think you already know this)

the collection of graphics have to be sent to the server feature by feature, with a symbol defined (not renderer, which supports a label), rather than having a true class breaks renderer defined for the feature layer. If the field was present on the server we could just describe the renderer as class breaks and let ArcGIS Server draw things up on the fly).

i tested actually adding a new field to the graphics layer based on this value instead of relying on a function within the renderer, but this doesn't work either (because when we send the new print request we now assume a field is present in the service that isn't actually there).

function addNewAttribute() {
     var myLayer = app.map.getLayer("CountyACSv4_5756");
  myLayer.fields.push({"alias": "PERCENTOLD",
                      "editable": false,
       "length" : null,
       "nullable" : true,
                            "name" : "PERCENTOLD",
       "type" : "esriFieldTypeString"
       });
  dojo.forEach(myLayer.graphics, function (graphic) {
    graphic.attributes.PERCENTOLD = (graphic.attributes.AGE65PLUS / graphic.attributes.POP0711 * 100);
  });
   }

unfortunately, i don't know how of a good way to work around this problem (other than ensuring that you have fields present in the data for values you need to render by.)

Re: Print Widget and Renderers with Functions

DanielTrone — Thu, 16 May 2013 14:28:48 GMT

As far as not being able to include a legend for calculated values - that's too bad. I may have to restructure the data to work around this limitation - but as it was, I was already running up against the 256 column limit in shapefiles. (The American Community Survey is a huge, huge dataset).

One last point, however, what's going on with the layer transparency in the printouts?

1.) In my fiddle, http://jsfiddle.net/DanielTrone/xrGPh/2/ the transparency displays correctly in the printout; the basemap can be seen underneath the data layer.

2.) In your fiddle, http://jsfiddle.net/jagravois/A6cuH/ where we use the MED_AGE statistic directly, the transparency of the layer in the printout does not respect the transparency defined in the class breaks renderer. It is completely opaque.

Any idea what's happening here, so I can seek to get the correct behavoir (transparency of example 1, with legend of example 2).

Re: Print Widget and Renderers with Functions

JohnGravois — Sat, 11 Dec 2021 23:58:55 GMT

sorry for the delayed reply. i did some more testing and confirmed that this is a REST problem (as opposed to a problem in the JS API). it seems that currently ArcGIS Server does not honor transparency defined as an alpha value within a RGB color symbol for feature service layers.

you can see this problem by removing the .TXT extension from the attached .webmap file (which has identical contents to the webmap JSON we pass to ArcGIS Server when printing) and dragging and dropping itdirectly into ArcMap.

"symbol" : {
    "color" : [0, 255, 0, 128], //128 (or 50% transparency) is replaced by 255
    "outline" : {
        "color" : [0, 0, 0, 128],  //128 (or 50% transparency) is replaced by 255
        "width" : 2,
        "type" : "esriSLS",
        "style" : "esriSLSSolid"
    },
    "type" : "esriSFS",
    "style" : "esriSFSSolid"
},

even though an alpha transparency of 128 is specified for the symbol fill color, the layer is completely opaque in ArcMap

[ATTACH=CONFIG]25482[/ATTACH]

since your sample app passes a collection of graphics instead of a feature service layer, you get around this limitation (but encounter another).

ive asked the developers to update the Export Web Map Spec to acknowledge the limitation i found. sorry for the inconvenience.

Re: Print Widget and Renderers with Functions

DanielTrone — Sat, 11 Dec 2021 23:58:58 GMT

Thanks for the update. It's good to know that it's not necessarily anything I'm doing wrong. I've never had any formal javascript education, so sometimes I just assume my problems are a result of subtleties that I don't yet understand.

FWIW, I found an easy workaround to this problem via CSS:

    #legendDiv path{
    fill-opacity:0.6 !important;
    }

I hope this helps someone else out there!

Re: Print Widget and Renderers with Functions

ChrisVradis — Mon, 30 Dec 2013 13:05:28 GMT

Hello,
I am having the exact same problem - a feature layer with a function renderer. The legend appears fine with the Javascript API. When I try to print with the Print Task, the colours look fine (although not in correct order) but the name next to the symbol patch is replaced with the word "Override". In my case, the feature layer service on the server cannot access the data from which the renderer is created, since a) they are organized as numerous files not in a database and b) the algorithm that the break values are calculated runs in the browser (in javascript).

I was thinking about creating a class break and assign it temporarily to the feature layer, but I understand that access to data on the server is critical.

Are there any alternate solutions to this problem? W

Thanks.

Re: Print Widget and Renderers with Functions

BillLotz — Sat, 11 Dec 2021 23:59:00 GMT

Hello, any idea if a fix is in the works for this?

sorry for the delayed reply. i did some more testing and confirmed that this is a REST problem (as opposed to a problem in the JS API). it seems that currently ArcGIS Server does not honor transparency defined as an alpha value within a RGB color symbol for feature service layers.

you can see this problem by removing the .TXT extension from the attached .webmap file (which has identical contents to the webmap JSON we pass to ArcGIS Server when printing) and dragging and dropping itdirectly into ArcMap.
"symbol" : {
    "color" : [0, 255, 0, 128], //128 (or 50% transparency) is replaced by 255
    "outline" : {
        "color" : [0, 0, 0, 128],  //128 (or 50% transparency) is replaced by 255
        "width" : 2,
        "type" : "esriSLS",
        "style" : "esriSLSSolid"
    },
    "type" : "esriSFS",
    "style" : "esriSFSSolid"
},
even though an alpha transparency of 128 is specified for the symbol fill color, the layer is completely opaque in ArcMap

[ATTACH=CONFIG]25482[/ATTACH]

since your sample app passes a collection of graphics instead of a feature service layer, you get around this limitation (but encounter another).

ive asked the developers to update the Export Web Map Spec to acknowledge the limitation i found. sorry for the inconvenience.

Re: Print Widget and Renderers with Functions

JohnGravois — Tue, 04 Mar 2014 15:50:50 GMT

Bill,

this is unfortunately still considered a known limit. i went ahead and logged an issue requesting that it be revisited in the future on your behalf.

[NIM099543: Add support for transparency in color's alpha value when printing feature layers.]

sorry for the inconvenience.

Re: Print Widget and Renderers with Functions

BillLotz — Mon, 23 Jun 2014 18:59:13 GMT

Bill,

this is unfortunately still considered a known limit. i went ahead and logged an issue requesting that it be revisited in the future on your behalf.

[NIM099543: Add support for transparency in color's alpha value when printing feature layers.]

sorry for the inconvenience.

Thanks. For some reason I thought this was fixed in 10.2.2, but I guess it isn't.

Re: Print Widget and Renderers with Functions

ChrisSmith7 — Tue, 24 Feb 2015 19:38:53 GMT

I'm having a similar problem - we have an application that is joining dynamic JSON data to a map service by a unique ID shared between the JSON dataset and the map service... everything works brilliantly in our application, although we ended-up creating a custom breaks function; however, when we "print" the map using the default template, the LegendLayer passed to the server ends-up overriding the break labels rendering in the application with "override 1", "override 2", etc., like what is seen in Daniel's attachment (exOverride.pdf).

The resolution, it seems from John Gravois' previous response, is to ensure the map service contains the field/data... unfortunately, this isn't an option for us. Has anyone had success with a workaround? My initial thought was to create a custom template where we could send an HTML object from the client-side (the object being the legend) - I haven't come across supporting documentation yet to pursue this... we are currently using the default print template.

Thanks!

Re: Print Widget and Renderers with Functions

Anonymous User — Tue, 04 Aug 2015 19:56:20 GMT

Same issue here...UniqueValueRenderer with a function. Plopping a client-side legend into the print layout would be very handy.

Long-shot but, in the Print Template task the API can accept 'customTextElements' in the layout options. Is there some way to draw SVG and labels that could get put into a snapshot and inserted as png into the print output?

Re: Print Widget and Renderers with Functions

davetinkle — Wed, 24 Jan 2018 00:14:54 GMT

...coming up on 5 years and API version 4.6 still shows "Override 1" in the PDF print task output.

any fix, or even a work around?

any acknowledgement this is a bug, or a correction if not?

thanks.