Saving and getting information from Titanium MapView Annotation - titanium

Question

I have the following code that creates a new annotation on my .js:
//Create annotation
var new_annotation = Titanium.Map.createAnnotation({
latitude:10,
longitude:30,
title:"Title",
pincolor:Titanium.Map.ANNOTATION_RED,
customdata:"My custom data",
animate:true,
rightButton: Titanium.UI.iPhone.SystemButton.DISCLOSURE,
myid:1
});
$.mapview.addAnnotation(new_annotation);
All information like title, latitude and longitude is available on my click function:
function doClick(evt){
alert("title: " + evt.title);
alert("customdata: " + evt.customdata);
};
However customdata is "undefined".
How can save and retrieve data from a Titanium MapView Annotation? Why the data is "undefined"?

Answer 1

You are adding your customdata object to the annotation itself, the evt object that is passed into the click event listener is defined in the DOCS as passing the title of the annotation explicitly, so of course you can retrive it, but to get the customdata you have to do this:
function doClick(evt){
alert("title: " + evt.title);
// Get the annotation, then get the custom data attached to it
alert("customdata: " + evt.annotation.customdata);
};