iOS: convert view layout to single image using toImage()

app.js

var win = Ti.UI.createWindow({backgroundColor:'white'});
win.open();

// build our layout with 2 views and 1 imageView
var mainView = Ti.UI.createView({top:10,height:200,width:200,backgroundColor:'blue'});
var view2 = Ti.UI.createView({height:100,width:100,backgroundColor:'green'});
var imageView = Ti.UI.createImageView({image:'http://www.appcelerator.com/wp-content/uploads/2011/01/Appcelerator-IDC-Q1-Mobile-Developer-Report-appclogo.png'});
mainView.add(view2);
view2.add(imageView);

// this imageView will display the entire layout from above but will be lighter because it is only one imageView
var singleImage = Ti.UI.createImageView({top:220,height:200,width:200,backgroundColor:'red'});
win.add(singleImage);

convertViewToBlob(mainView, imageView, function(blob){
	singleImage.image = blob;
});

// will do toImage 2x: once immediately and then again when 'imageToLoad' loads
function convertViewToBlob(view, imageToLoad, callback){
	imageToLoad.addEventListener('load', runOnLoad);
	
	function runOnLoad(){
		imageToLoad.removeEventListener('load', runOnLoad);
		convertView(true);
	}
	
	view.top = 2000;
	convertView();
	
	function convertView(/*bool*/ isDestructive){		
		var blob = view.toImage();	
		
		if(callback){
			callback(blob);
		}
	};
}