topic Re: definition expression on hosted portal layers? in ArcGIS JavaScript Maps SDK Questions

definition expression on hosted portal layers?

TimLohnes1 — Wed, 31 Jan 2024 00:45:30 GMT

Hi,

I'm switching my layers over to hosted feature layers on our portal. I have a javascript map that consumes the data and presents the layer differently based on what user's select.

The way I'm currently doing it is changing the definitionExpression on the layer based on selection.

Now when I'm adding a layer from portalItem

var streetPavingHostedLayer = Layer.fromPortalItem({

portalItem: {

// autocasts as new PortalItem()

id: "xxxxxxxxxxxxxxxxxx",

portal: {

url: "https://xxxxxxxxxxxx/portal"

}

});

The above adds the whole layer. But the below doesn't filter correctly. I can't make heads or tails when I inspect the errors. Doesn't point to my code.

Can I add a definition expression, like definitionExpression: "roadname = 'CHABOT CT'"? I can't get it to work. Wondering if it doesn't work or I'm just formatting the expression wrong.

If I can't do this, wondering if my best bet is to make a different view for each way I want to portray the layer and then just call the layer desired when selected by user?

Thanks for any thoughts.

-Tim

Re: definition expression on hosted portal layers?

UndralBatsukh — Wed, 31 Jan 2024 15:05:59 GMT

Hi there,

That definitionExpression looks valid to me. Is it possible for you to shrare your data with me so I can take a look? The following example works.

const view = new MapView({ container: "viewDiv", map: map, center: [-122.907, 47.018], zoom:12 }); const featureLayer = new FeatureLayer({ url: "https://data.wsdot.wa.gov/arcgis/rest/services/Shared/LocalAgencyPublicRoadData/FeatureServer/0", definitionExpression: "RoadName = 'Columbia St NW'" });

Re: definition expression on hosted portal layers?

TimLohnes1 — Fri, 02 Feb 2024 00:53:10 GMT

Thanks, @UndralBatsukh The code you showed is how I'm using it now. I'm wondering if using layers created from portal have the same capability of using the definitionExpression? See my code above. Thanks.

Here is an example layer, https://maps.hayward-ca.gov/portal/home/item.html?id=5663a61146c648ca9fd674b58693de47

Re: definition expression on hosted portal layers?

UndralBatsukh — Fri, 02 Feb 2024 02:10:33 GMT

The definitionExpression does work for your service. Looks like it is a really small road - https://codepen.io/U_B_U/pen/abMYXbG?editors=1000

Re: definition expression on hosted portal layers?

TimLohnes1 — Fri, 02 Feb 2024 17:28:14 GMT

Awesome. Thanks. Looks a lot simpler the way you are doing it. Perfect.