topic Re: Display selective features from a layer? in ArcGIS JavaScript Maps SDK Questions

Display selective features from a layer?

JatinPatel — Mon, 12 Aug 2013 17:10:09 GMT

I have a layer (Not a feature layer). Is it possible to display only a few selected (based on a query) features from that layer on the map?

Re: Display selective features from a layer?

KenBuja — Mon, 12 Aug 2013 18:20:56 GMT

The layerDefinitions property can be used to filter the features of the individual layers in a map service. Take a look at the code snippet.

Re: Display selective features from a layer?

JatinPatel — Thu, 29 Aug 2013 14:35:31 GMT

Thanks Ken!!

Re: Display selective features from a layer?

JatinPatel — Thu, 29 Aug 2013 15:14:45 GMT

The layerDefinitions property can be used to filter the features of the individual layers in a map service. Take a look at the code snippet.

Ken,
Is it possible to set a criteria using geometry in this case?

Re: Display selective features from a layer?

ZachLiu1 — Thu, 29 Aug 2013 16:26:47 GMT

Do you mean selection by location?

You can define a QueryTask and in your Query definition you can set your query geometry and type of relationship, and display only the features you want in a graphic layer.

Hope this will help.

Re: Display selective features from a layer?

JatinPatel — Thu, 29 Aug 2013 16:43:26 GMT

Do you mean selection by location?

You can define a QueryTask and in your Query definition you can set your query geometry and type of relationship, and display only the features you want in a graphic layer.

Hope this will help.

Querytask will not work. It can only create a dummy graphic on top of the layer, I would like to actually display the layer itself with only the features that fall inside a certain geometry, just like layerDefinitions for an attribute criteria.

Re: Display selective features from a layer?

JasonZou — Thu, 29 Aug 2013 17:40:46 GMT

There is no easy solution for what you need. One option I can think of is like the following workflow.

Create a feature layer

Set its renderer to blank symbol so that no features will be displayed.

setSelectionSymbol to symbols for the selected features.

Use selectFeatures to apply the criteria defined by both attributes and geometries.

This way, it will only display the features filtered by attributes and geometries.

Re: Display selective features from a layer?

VinayBansal — Fri, 30 Aug 2013 11:42:08 GMT

There is no direct solution. Other option can be....

Use querytask to get the objectIds of the features of layer within the geometry.
And then set the layerDefinitionExpression for the the layer by passing the returned ObjectIds. Like OBJECTID IN (1,2,3.......)

But there might be the limitations of number of objectid's to be passed to the layerdefinition expression. If records returned are more...

Re: Display selective features from a layer?

JatinPatel — Wed, 04 Sep 2013 11:25:17 GMT

There is no direct solution. Other option can be....

Use querytask to get the objectIds of the features of layer within the geometry.
And then set the layerDefinitionExpression for the the layer by passing the returned ObjectIds. Like OBJECTID IN (1,2,3.......)

But there might be the limitations of number of objectid's to be passed to the layerdefinition expression. If records returned are more...

Thanks Vinay... I think that will solve my problem...!!

Re: Display selective features from a layer?

AlessioDi_Lorenzo — Thu, 19 Sep 2013 12:49:05 GMT

There is no direct solution. Other option can be....

Use querytask to get the objectIds of the features of layer within the geometry.
And then set the layerDefinitionExpression for the the layer by passing the returned ObjectIds. Like OBJECTID IN (1,2,3.......)

But there might be the limitations of number of objectid's to be passed to the layerdefinition expression. If records returned are more...

Hi,

I am using exactly this approach to obtain a server-side response to a buffer query. The problem is that it works until the returned features (points, in my case) are 999. Then arcgis server returns a blank image in my arcgisoutput directory.
I already set the maxRecordCount variable to 5000.
Any help?
Thank you!

Re: Display selective features from a layer?

JasonZou — Thu, 19 Sep 2013 14:14:40 GMT

maxRecordCount is a read-only property which is carried over from the map service. The only way you can increase the limit is to change maxRecordCount of a map service using ArcGIS Server Manager or ArcCatalog. Once set and published, maxRecordCount cannot be changed. In addition, maxRecordCount can only be set at the map service level, not the feature layer level. I've had a hard time to find it out.

To ESRI development team: it's truely beneficial to be able to change maxRecordCount at both map service and feature layer level via JSAPI. One scenario we have experienced is that our app has to support both IE8 and other modern browsers. Since IE8 is much slower in Javascript execution, we have the need to limit maxRecordCount to 500 for IE8 users, and keep 1000 or even 2000 for other users.

Re: Display selective features from a layer?

AlessioDi_Lorenzo — Thu, 19 Sep 2013 14:45:18 GMT

maxRecordCount is a read-only property which is carried over from the map service. The only way you can increase the limit is to change maxRecordCount of a map service using ArcGIS Server Manager or ArcCatalog.

hi zj_zou,

this is what I've done and infact my queryTask returns results for more than 1000 features (the default value).

My problem is that when I use the objectids returned by the query in the layerDefinitions expression ( OBJECTID IN ('1','2',...) ) and the result of this filtering operation is grater than 1000, the respose from the server is a blank image

739 objectids passed in the definition expression:
[ATTACH=CONFIG]27585[/ATTACH]

1160 objectids passed in the definition expression:
[ATTACH=CONFIG]27586[/ATTACH]

Re: Display selective features from a layer?

JasonZou — Thu, 19 Sep 2013 14:51:53 GMT

The feature limit does not apply to featureLayer.queryIds. Here is the description of the method on ESRI API description.

Query for ObjectIds. There is no limit on the number of ObjectIds that are returned from the server.

But I believe the feature limit does apply to setDefinitionExpression.

Re: Display selective features from a layer?

AlessioDi_Lorenzo — Thu, 19 Sep 2013 15:29:05 GMT

Ok, does exist a way to go beyond this limitation?
For various reasons I have to use a dynamic map service layer to represent the buffer response

Thx

Re: Display selective features from a layer?

JasonZou — Thu, 19 Sep 2013 15:40:14 GMT

Not I know of. As far as I know, the only way is to increase the limit using ArcGIS Server Manager.

Re: Display selective features from a layer?

AlessioDi_Lorenzo — Thu, 19 Sep 2013 16:38:17 GMT

As far as I know, the only way is to increase the limit using ArcGIS Server Manager.

Of course, but this is NOT the problem, because the maxrecordcount variable affects the queryTask, while I'm trying to understand what happens using the query task results, in the form of a string, as argument of the IN clause in a layerDefinitions object.

Later I will try to post some code...

Re: Display selective features from a layer?

AlessioDi_Lorenzo — Tue, 24 Sep 2013 16:36:27 GMT

Solved using geoprocessing service with a result map