topic Re: Changing definitionExpression doesn't work in ArcGIS JavaScript Maps SDK Questions

Changing definitionExpression doesn't work

MohamedHamoud — Tue, 07 Jun 2016 08:41:39 GMT

definitionExpression attribute of FeatureLayer works fine when the application is loaded, but when I click a button that changes the definitionExpression attribute of the layer, the displayed features disappear from the map but I don't see the new features based on the new definitionExpression, although the attribute is changed.

The code I am using:


	var buildingsLyr = new FeatureLayer({
	url: "myURL",
	id: "BuildingsBM",
	renderer: renderer,
	popupTemplate: {
	title: "{ID}",
	content: "{*}"
	},
	outFields: ["ID", "Use", "Z"],
	definitionExpression: "Sector = 'S1'", // show only buildings within this sector
	});

	map = new Map({
	basemap: "streets",

	layers: [buildingsLyr]
	});

	view = new SceneView({
	container: "viewDiv",
	map: map
	,
	camera: {
	position: [54, 24, 30000],
	heading: 0,
	tilt: 35
	}
	});

// on button click, change the definitionExpression

	on(document.getElementById("btnLocate"), "click", function (e) {

	buildingsLyr.definitionExpression = "Sector = 'S2'"
	});

Re: Changing definitionExpression doesn't work

FC_Basson — Tue, 07 Jun 2016 08:56:43 GMT

Try setting the definition expression after the layer load.

Re: Changing definitionExpression doesn't work

MohamedHamoud — Tue, 07 Jun 2016 10:24:21 GMT

This is what I am doing, but the layer is disappearing after I change definitionExpression

Re: Changing definitionExpression doesn't work

MohamedHamoud — Tue, 07 Jun 2016 10:59:51 GMT

To simulate my case, you may check the following example:

ArcGIS API for JavaScript Sandbox

And use the following updated code, then after clicking the button on the top of the map, the building's layer is disappearing:

<!DOCTYPE html>

<html>

<head>

<title>Extrude building footprints based on real world heights - 4.0</title>

<style>

html,

body,

#viewDiv {

padding: 0;

margin: 0;

height: 100%;

width: 100%;

}

</style>

require([

"esri/Map",

"esri/views/SceneView",

"esri/layers/FeatureLayer",

"esri/renderers/UniqueValueRenderer",

"esri/symbols/ExtrudeSymbol3DLayer",

"esri/symbols/PolygonSymbol3D",

"dojo/on",

"dojo/domReady!"

], function(

Map, SceneView, FeatureLayer, UniqueValueRenderer,

ExtrudeSymbol3DLayer, PolygonSymbol3D, on

) {

/*****************************************************************

* Define symbols for each unique type of building. One each for

* residential, condos, and other.

*****************************************************************/

var resSym = new PolygonSymbol3D({

symbolLayers: [

new ExtrudeSymbol3DLayer({

material: {

color: "#FC921F"

}

})

]

});

var condoSym = new PolygonSymbol3D({

symbolLayers: [

new ExtrudeSymbol3DLayer({

material: {

color: "#9E559C"

}

})

]

});

/*****************************************************************

* Set each unique value directly in the renderer's constructor.

* At least one field must be used (in this case the "DESCLU" field).

* The label property of each unique value will be used to indicate

* the field value and symbol in the legend.

* The size visual variable sets the height of each building as it

* exists in the real world according to the "ELEVATION" field.

*****************************************************************/

var renderer = new UniqueValueRenderer({

defaultSymbol: new PolygonSymbol3D({

symbolLayers: [new ExtrudeSymbol3DLayer({

material: {

color: "#A7C636"

}

})]

}),

defaultLabel: "Other",

field: "DESCLU",

visualVariables: [{

type: "size",

field: "ELEVATION",

valueUnit: "feet" // Converts and extrudes all data values in feet

}]

});

// Set the renderer on the layer

var buildingsLyr = new FeatureLayer({

url: "https://services1.arcgis.com/jjVcwHv9AQEq3DH3/ArcGIS/rest/services/Buildings/FeatureServer/0",

renderer: renderer,

popupTemplate: {

title: "{DESCLU}",

content: "{*}"

outFields: ["ADDRESS", "DESCLU", "ELEVATION"],

definitionExpression: "ELEVATION > 0", // show only buildings with height

});

var map = new Map({

basemap: "streets",

ground: "world-elevation",

layers: [buildingsLyr]

});

var view = new SceneView({

container: "viewDiv",

map: map,

camera: {

position: {

x: -8354148,

y: 4641966,

z: 129,

spatialReference: {

wkid: 3857

}

heading: 300,

tilt: 75

}

});

on(document.getElementById("ChangeExpression"), "click", function (e) {

buildingsLyr.definitionExpression = "ELEVATION > 30"

//alert(buildingsLyr.definitionExpression);

});

</script>

</head>

<body>

<button id="ChangeExpression">ChangeExpression</button>

</body>

</html>

Re: Changing definitionExpression doesn't work

FC_Basson — Sun, 12 Dec 2021 08:09:30 GMT

The scope of your buildingsLayer variable is not right. Define the variable before the require statement.

var buildingsLyr;
require([...

Re: Changing definitionExpression doesn't work

MohamedHamoud — Tue, 07 Jun 2016 12:22:27 GMT

didn't work

Re: Changing definitionExpression doesn't work

MohamedHamoud — Tue, 07 Jun 2016 12:24:58 GMT

Dears,

I made a fiddle to simulate the problem:

Edit fiddle - JSFiddle

Run the page and wait until the buildings are added to the map, then click on "ChangeExpression" button. The expected result is that only buildings higher then 30will be visible. The actual result is that all buildings are disappearing.

Re: Changing definitionExpression doesn't work

FC_Basson — Tue, 07 Jun 2016 12:25:44 GMT

Well, I tried the code you provided and changed it as I advised and it worked. Did you remove the buildingsLayer variable declaration further down in the require function?

Re: Changing definitionExpression doesn't work

FC_Basson — Tue, 07 Jun 2016 12:33:18 GMT

Here's an updated working fiddle :Edit fiddle - JSFiddle

Re: Changing definitionExpression doesn't work

MohamedHamoud — Tue, 07 Jun 2016 12:33:28 GMT

Here is the fiddle with your advised code. Still not working for me:

Edit fiddle - JSFiddle

Re: Changing definitionExpression doesn't work

FC_Basson — Tue, 07 Jun 2016 12:36:21 GMT

Completing your Javascript line statements with a semi-colon is good practice.

buildingsLyr.definitionExpression = "ELEVATION > 30";

Re: Changing definitionExpression doesn't work

MohamedHamoud — Tue, 07 Jun 2016 12:36:32 GMT

Thank you. But still not workingfor me.

It works only if I clicked the button while the buildings are being loaded. But if I click the button after all buildings are completed loding then all buildings disappears.

Re: Changing definitionExpression doesn't work

FC_Basson — Tue, 07 Jun 2016 13:16:41 GMT

Funny enough, if you set the layer definition expression through the browser console, then the button click works afterwards.

Re: Changing definitionExpression doesn't work

FC_Basson — Wed, 08 Jun 2016 07:21:01 GMT

Hi Mohamed. Take a look at this fiddle: Edit fiddle - JSFiddle . I've added buttons to increase and decrease the building elevation. I have to agree with you that the behaviour is "buggy". I also suspect that it might have something to do with the maximum feature count provided by the REST endpoint (2000).

Re: Changing definitionExpression doesn't work

MohamedHamoud — Wed, 08 Jun 2016 07:49:49 GMT

Dear FC Basson,

Thank you very much for your help.

I tried your nice last fiddle and found that on some clicks the result is as expected, and on others it is not.

I hope that esri's java script API team to look at this issue and fix it.

Re: Changing definitionExpression doesn't work

FC_Basson — Wed, 08 Jun 2016 07:54:45 GMT

No problem. I think the 4.1 release will include some major improvements.