geo lookup from google api sample code which uses callback query string to load <script> for gmaps api only if element exists on page

geolookup.js

/*!
* GeoLocation
* @requires jQuery v1.7.2+
*
* Description
* auto-populates a field with geo-location data
*/
; (function ($) {

    window.Motorama.geoLocation = window.Motorama.geoLocation || window.Motorama.BaseModule(function () {

        var _self, $el, $locationField, geocoder;
        
        //Get geolocation lat & long and format it to address location
        function codeLatLng(lat, lng) {
            var latlng = new google.maps.LatLng(lat, lng);
            geocoder.geocode({ 'latLng': latlng }, function (results, status) {
                if (status == google.maps.GeocoderStatus.OK) {
                    if (results[1]) {
                        //formatted address
                        $locationField.val(results[0].formatted_address);

                        //find country name
                        for (var i = 0; i < results[0].address_components.length; i++) {
                            for (var b = 0; b < results[0].address_components[i].types.length; b++) {
                                //there are different types that might hold a city admin_area_lvl_1 usually does in come cases looking for sublocality type will be more appropriate
                                if (results[0].address_components[i].types[b] == "administrative_area_level_1") {
                                    //this is the object you are looking for
                                    var city = results[0].address_components[i];
                                    break;
                                }
                            }
                        }                        
                    }
                    else {
                        console.log("No results found");
                    }
                }
                else {
                    console.log("Geocoder failed due to: " + status);
                }
            });
        }

        //Get the latitude and the longitude;
        function geoLocationSuccess(position) {
            var lat = position.coords.latitude;
            var lng = position.coords.longitude;
            codeLatLng(lat, lng);
        }
        
        function geoLocationError() {
            console.log('unable to load geo-location data');
        }
        
        return {
            init: function () {
                _self = this;
                $el = $('body');
                $locationField = $('.geoLocationInputField input');                                                            

                if ($locationField != undefined && $locationField.length > 0) {
                    this.methods.loadGMapScript();                    
                }
            },            
            methods: {
                /*gmaps api has its own script calls inside of it so we need to wait until they have also loaded before coming back to
                do this we can add 'callback= ' as a query string to the script src options and add our own method to the end once its returned*/
                loadGMapScript: function() {                                        
                    var script = document.createElement("script");
                    script.type = "text/javascript";
                    script.src = "http://maps.google.com/maps/api/js?sensor=false&callback=Motorama.geoLocation.methods.intializeMap";
                    script.async = true;
                    document.body.appendChild(script);
                },
                intializeMap: function() {
                    geocoder = new window.google.maps.Geocoder();                    
                    if (navigator.geolocation) {
                        navigator.geolocation.getCurrentPosition(geoLocationSuccess, geoLocationError);
                    }
                }            
            }                            
        };
        
    }());
})(jQuery);