Android: download pdf and save it to the sdcard

app.js

var win = Ti.UI.createWindow({
	navBarHidden: true,
	backgroundColor: 'blue'
});
win.open();

var button = Ti.UI.createButton({
	title: 'Get PDF',
	height: 50,
	width: 200,
	top: 20
});
win.add(button);
button.addEventListener('click', function(e) {
	var xhr = Ti.Network.createHTTPClient();
	xhr.onload = function() {
		var f = Ti.Filesystem.getFile(Titanium.Filesystem.externalStorageDirectory,"test.pdf");
		f.write(this.responseData);
		var intent = Ti.Android.createIntent({
			action : Ti.Android.ACTION_VIEW,
			type : 'application/pdf',
			data : f.getNativePath()
		});
		Ti.Android.currentActivity.startActivity(intent);
	};

	xhr.open("GET", "http://www.appcelerator.com/assets/The_iPad_App_Wave.pdf");
	xhr.send();
});