topic Re: Layer order in a legend in ArcGIS JavaScript Maps SDK Questions

Layer order in a legend

PitersonPaulgek — Wed, 23 Nov 2016 06:31:52 GMT

Hi,

There is no order by geometry type in a legend created with a legend widget.

How layers can be ordered? Generally, we need to implement the rule:

- points

- lines

- polygons

bottom - polygons.

Any help will be appreciated.

Re: Layer order in a legend

PanagiotisPapadopoulos — Wed, 23 Nov 2016 08:26:50 GMT

the property define the layer order on Legend Widget according to the Javascript Help is the LayerInfos

see below.

<Object[]> layerInfos Optional Specify a subset of the layers in the map to display in the legend. If not set, all layers in the map will display in the legend. The order of the layers in the legend depends on the layerInfo array. See the layerInfos property description for a description of its object properties.

So during the layer load on the map change the layer order.

Re: Layer order in a legend

PanagiotisPapadopoulos — Wed, 23 Nov 2016 08:52:24 GMT

this is a sample code

......
//add the legend
map.on("layers-add-result", function (evt) {
var layerInfoLines = [];
arrayUtils.map(evt.layers, function (layer, index) {
if (layer.layer.geometryType === "esriGeometryPolyline"){
layerInfoLines.push({layer:layer.layer, title:layer.layer.name});
}
});
var layerInfoPolygons = [];
arrayUtils.map(evt.layers, function (layer, index) {
if (layer.layer.geometryType === "esriGeometryPolygon"){
layerInfoPolygons.push({layer:layer.layer, title:layer.layer.name});
}
});
var layerInfo = layerInfoPolygons.concat(layerInfoLines);

if (layerInfo.length > 0) {
var legendDijit = new Legend({
map: map,
layerInfos: layerInfo
}, "legendDiv");
legendDijit.startup();
}
});

.....

and here see a live sample

Edit fiddle - JSFiddle

Re: Layer order in a legend

PitersonPaulgek — Fri, 25 Nov 2016 00:21:33 GMT

Thank you for response, Panagiotis Papadopoulos.

Unfortunately, we have no geometry type when working with ArcGISDynamicMapServiceLayer.

So, how we obtain that geometryType?

Re: Layer order in a legend

KenBuja — Fri, 25 Nov 2016 14:15:54 GMT

See this discussion: https://community.esri.com/message/80485