JavaScript: Adding/removing layers from ArcGIS Server

Question

I've developed an application which loads the services from the ArcGIS Server via REST API.

Each service has multiple layers, and I can check/uncheck any layer. The problem is the layers are loaded via one URL, and each time I have to remove all layers of the service and load again.

Is there a better way?

• Vince: No. Loading each layer as a service would be extremely wasteful of Server resources, and result in awful performance.
• Dowlers: I don't understand. You have to remove all layers just to turn one off?
• Leeloo: @Dowlers Is there another way?
• Dowlers: Using javascript? Yes there are several. layer.setVisibleLayers(ids, doNotRefresh?) is the easiest: developers.arcgis.com/javascript/3/jsapi/…
• Leeloo: @Dowlers Could you write in answer form?

Answer 1

Individual layers within a map service can be turned on or off using the esri javascript api. Look at the setVisibleLayers method of the dynamicmaplayer class: https://developers.arcgis.com/javascript/3/jsapi/arcgisdynamicmapservicelayer-amd.html#setvisiblelayers

It takes on array of layerIDs to make visible

require([
 "esri/layers/ArcGISDynamicMapServiceLayer" ,"dojo/query", ... 
], function(ArcGISDynamicMapServiceLayer, query, ... ) {
 var layer = new ArcGISDynamicMapServiceLayer( ... );
 var inputs = query(".list_item"), input;
 visible = [];
 for (var i=0, il=inputs.length; i< il; i++) {
 if (inputs[i].checked) {
 visible.push(inputs[i].id);
 }
 }
 layer.setVisibleLayers(visible);
 ...
});

• Leeloo: How to define layers? var layer = new ArcGISDynamicMapServiceLayer( ... ); What is in the brackets?
• Leeloo: Also, is says, ArcGISDynamicMapServiceLayer is not defined
• Dowlers: I think you need to go back and look at some of the samples on the javascript api website. Instantiating layers is a core part of the api and is covered in many of the samples. developers.arcgis.com/javascript/3/jssamples/…
• Leeloo: What about SetLayers from esri.github.io/esri-leaflet/api-reference/layers/… ?
• Dowlers: Oh you are using leaflet. I'm not as familiar with that but I think you are right. The setlayers method will take an array of layerids to show.