Creating an AttributeInspector via JavaScript API v2.7

I'm trying to display an AttributeInspector when I click on an object from a layer. I'm following this sample, but I cannot get it to work.

Here is my sample code:

dojo.require("esri.map");
dojo.require("esri.dijit.Scalebar");
dojo.require("dijit.layout.ContentPane");
dojo.require("esri.dijit.AttributeInspector-all");

var map;
var earthquakes, earthquakesFeatureLayer;
var visible;
var updateFeature;

function init() {
    esri.config.defaults.io.proxyUrl = "/arcgisserver/apis/javascript/proxy/proxy.ashx";

    var initExtent = new esri.geometry.Extent({
        "xmin":-1089520.5238523486,
        "ymin":4205238.517449941,
        "xmax":5392339.474728875,
        "ymax":7037689.037584678,
        "spatialReference": {
            "wkid":102100
        }
    });
    map = new esri.Map("map", { extent: initExtent });

    dojo.connect(map, "onLayersAddResult", initSelectToolbar);

    // National Geographic World Map
    var basemap = new esri.layers.ArcGISTiledMapServiceLayer("http://services.arcgisonline.com/ArcGIS/rest/services/NatGeo_World_Map/MapServer");
    map.addLayer(basemap);

   // set the image parameters to toggle layer visibility
    var imageParameters = new esri.layers.ImageParameters();
    imageParameters.layerIds = [1];
    imageParameters.layerOption = esri.layers.ImageParameters.LAYER_OPTION_SHOW;

    // Earthquakes From Last Seven Days
    earthquakes = new esri.layers.ArcGISDynamicMapServiceLayer(
            "http://sampleserver3.arcgisonline.com/ArcGIS/rest/services/Earthquakes/EarthquakesFromLastSevenDays/MapServer",
            {"imageParameters": imageParameters});
    earthquakes.setDisableClientCaching(true);
    map.addLayer(earthquakes);

    earthquakesFeatureLayer = new esri.layers.FeatureLayer(
            "http://sampleserver3.arcgisonline.com/ArcGIS/rest/services/Earthquakes/EarthquakesFromLastSevenDays/MapServer/0",
            {
                mode: esri.layers.FeatureLayer.MODE_SELECTION,
                            outFields: ["objectid", "datetime", "depth", "magnitude", "region"]
            });
    var selectionSymbol = new esri.symbol.SimpleFillSymbol(); 
    earthquakesFeatureLayer.setSelectionSymbol(selectionSymbol);

    dojo.connect(earthquakesFeatureLayer, "onEditsComplete", function() {
        earthquakes.refresh();
    });

    map.addLayer(earthquakesFeatureLayer);

    // add a scalebar to the map
    dojo.connect(map, 'onLoad', function(map) {
        var scalebar = new esri.dijit.Scalebar({
            map: map,
            scalebarUnit: 'english'
        });
    });
}

function initSelectToolbar(results) {
    var earthquakesFL = results[2].layer;
    var selectQuery = new esri.tasks.Query();
    console.log(results[2].success);

    dojo.connect(map, "onClick", function(evt) {
        selectQuery.geometry = evt.mapPoint;
        earthquakesFL.selectFeatures(selectQuery, esri.layers.FeatureLayer.SELECTION_NEW, function(features) {
            if (features.length > 0) {
                //store the current feature
                updateFeature = features[0];
                map.infoWindow.setTitle(features[0].getLayer().name);
                map.infoWindow.show(evt.screenPoint, map.getInfoWindowAnchor(evt.screenPoint));
            } else {
                map.infoWindow.hide();
            }
        });
    });

    dojo.connect(map.infoWindow, "onHide", function() {
        earthquakesFL.clearSelection();
    });

    var layerInfos = [{'featureLayer': earthquakesFL,
        'showAttachments':false,
        'isEditable': true,
        'fieldInfos': [
        {'fieldName': 'datetime', 'isEditable':true, 'label':'Earthquake Date:'},
        {'fieldName': 'depth', 'isEditable':true, 'label':'Depth:'},
        {'fieldName': 'magnitude', 'isEditable':false,'label':'Magnitude:'},
        {'fieldName': 'region', 'isEditable':false, 'label':'Region:'}
        ]}];

        var attInspector = new esri.dijit.AttributeInspector({
            layerInfos: layerInfos
        },
        dojo.create("div")
        );

        //add a save button next to the delete button
    var saveButton = new dijit.form.Button({label: "Save", "class": "saveButton"});
    dojo.place(saveButton.domNode, attInspector.deleteBtn.domNode, "after");

    dojo.connect(saveButton, "onClick", function() {
        updateFeature.getLayer().applyEdits(null, [updateFeature], null);
    });

    dojo.connect(attInspector, "onAttributeChange", function(feature, fieldName, newFieldValue) {
        //store the updates to apply when the save button is clicked 
        updateFeature.attributes[fieldName] = newFieldValue;
    });    

    dojo.connect(attInspector,"onNext", function(feature) {
        updateFeature = feature;
        console.log("Next " + updateFeature.attributes.objectid);
    });

    dojo.connect(attInspector, "onDelete", function(feature) {
        feature.getLayer().applyEdits(null, null, [feature]);
        map.infoWindow.hide();
    });

    map.infoWindow.setContent(attInspector.domNode);
    map.infoWindow.resize(325,210);
}

function updateLayerVisibility() {
    var inputs = dojo.query(".layer");
    visible = [];
    var inputsCount = inputs.length;
    for (var i = 0; i < inputsCount; i++) {
        if (inputs[i].checked) {
            visible.push(inputs[i].id);
        }
    }

    if (visible.length === 0) {
        visible.push(-1);
    }

    earthquakes.setVisibleLayers(visible);
}

dojo.addOnLoad(init);

The sample says I have to use a proxy to implement the example, but I'm not sure how to do it. Is it just a proxy issue that is getting in my way? Do you see any other problems in my code?

EDIT:

And here is the HTML:

<html>
  <head>
    <script type="text/javascript">var dojoConfig = {parseOnLoad: true};</script>
    <script src="http://serverapi.arcgisonline.com/jsapi/arcgis/?v=2.7" type="text/javascript"></script>
    <link href="http://serverapi.arcgisonline.com/jsapi/arcgis/2.8/js/dojo/dijit/themes/claro/claro.css" rel="stylesheet" text="text/css">
    <link href="styles.css" rel="stylesheet" text="text/css">
    <script src="sample.js" type="text/javascript"></script>
    <title>ArcGIS Project</title>
  </head>

  <body>
    <p>The following project is a HTML/JavaScript-based application, which uses the ESRI ArcGIS API for JavaScript v2.7</p>
    Layers List: 
    <span id="layers">
      <input type="checkbox" class="layer" id="0" value="0" onclick="updateLayerVisibility();"/> Earthquakes
    </span>
    <div id="map"></div>
  </body>

EDIT: It seems that the onLayersAddResult event never fires, therefor the initSelectToolbar function never gets called. Why is this happening? What am I doing wrong?