Add route to an Apple Map using Google Maps Directions API in Titanium (Alloy).

gistfile1.js

// setup geolocation purpose and accuracy
Ti.Geolocation.accuracy = Ti.Geolocation.ACCURACY_BEST;
Ti.Geolocation.purpose = L('geo-purpose');

// setup map and poi's annotation
var latitude = 48.847684,
    longitude = 2.35165;

var annotation = Titanium.Map.createAnnotation({
	animate: true,
	pincolor: Titanium.Map.ANNOTATION_PURPLE,
	title: L('name'),
	subtitle: L('address'),
	latitude: latitude,
	longitude: longitude
});

$.mapView.animate = true;
$.mapView.regionFit = true;
$.mapView.userLocation = true;
$.mapView.region = {
	latitude: latitude,
	longitude: longitude,
	latitudeDelta: 0.01,
	longitudeDelta: 0.01
};

$.mapView.addAnnotation(annotation);
$.mapView.selectAnnotation(annotation);

// route
$.btnRoute.addEventListener('click', function(){
  Ti.Geolocation.getCurrentPosition(function(e){
		// user's pin
		var userAnnotation = Titanium.Map.createAnnotation({
			animate: true,
			pincolor: Ti.Map.ANNOTATION_PURPLE,
			title: L('your-position'),
			latitude: e.coords.latitude,
			longitude: e.coords.longitude
		});
		
		$.mapView.addAnnotation(userAnnotation);
		
		
		
	// call Google Maps API and parse xml
	var data = [];
    var url = "http://maps.googleapis.com/maps/api/directions/xml?origin=" + e.coords.latitude + ',' + e.coords.longitude + "&destination=" + latitude + ',' + longitude + "&sensor=false";
    var xhr = Titanium.Network.createHTTPClient();
    xhr.open('GET', url);
	
    xhr.onload = function(){
        var xml = this.responseXML;
        var points = [];
        var steps = xml.documentElement.getElementsByTagName('step');
        var numSteps = steps.length;
				
        for(var i = 0; i< numSteps; i++)
        {
        	var step = steps.item(i);
        	var endLocation = step.getElementsByTagName('end_location').item(0);
        	var lat = endLocation.getElementsByTagName('lat').item(0).text;
        	var lng = endLocation.getElementsByTagName('lng').item(0).text;

        	points.push({
        		latitude: lat,
        		longitude: lng
        	});
        }
        
        // create route
        var route = {
            name: 'My Route',
            points: points,
            color: 'purple',
            width: 3
        };

        // add a route
        $.mapView.addRoute(route);
    };
    
    xhr.send();
    
	});
});