(ArcGIS API for JavaScript) Sample for orderByFields using classBreaksRenderer

Sample.js

require(["esri/map",
    "esri/layers/FeatureLayer",
    "esri/renderers/ClassBreaksRenderer",
    "esri/symbols/SimpleMarkerSymbol",
    "esri/Color",
    "esri/symbols/SimpleLineSymbol",
    "esri/tasks/query",
    "dojo/domReady!"
], function (Map, FeatureLayer, ClassBreaksRenderer, SimpleMarkerSymbol, Color, SimpleLineSymbol, Query) {

    var map = new Map("map", {
        center: [-118, 34.5],
        zoom: 4,
        basemap: "topo"
    });

    var sms = new SimpleMarkerSymbol(SimpleMarkerSymbol.STYLE_CIRCLE, 10, null, new Color("red"));

    var renderer = new ClassBreaksRenderer(sms, "ELEVATION");

    renderer.setVisualVariables([{
            type: "sizeInfo",
            field: "ELEVATION",
            minSize: 5,
            maxSize: 50,
            minDataValue: 90,
            maxDataValue: 1000
        },
        {
            type: "sizeInfo",
            field: "POP1990",
            minSize: 2,
            maxSize: 10,
            minDataValue: 10000,
            maxDataValue: 15000
        },
        {
            type: "colorInfo",
            field: "ELEVATION",
            stops: [{
                    value: 0,
                    color: new Color("white")
                },
                {
                    value: 1000,
                    color: new Color("black")
                }
            ]
        }
    ]);

    var fl = new FeatureLayer("link to a specific feature layer", {
        outfields: ["*"],
        orderByFields: ["ELEVATION DESC", "POP1990"]
    });

    fl.setRenderer(renderer);

    map.addLayer(fl);
});