XHR function with callback

app.js

HTTPRequest({
		ur:'http://example.com/somefile.json',
		type:'GET',
		success: function(a){
			var json = JSON.parse(a);
			// do something else
		},
		error: function(response, message){
			// handle error
		}
});

xhr.js

function HTTPRequest(params){
	
	if(!params || !params.url){
		alert('No params passed!!');
		return;
	}
	
	if(!params.success){
		alert('Give the XHR call a success callback!!');
		return;
	}
	if(!params.error){
		alert('Give the XHR call an error callback!!');
		return false;
	}
	if(!params.type){ params.type = 'GET'; }
	
	var xhr = Ti.Network.createHTTPClient();
	
	xhr.onload = function(){
		params.success(this.responseText);
	};
	
	xhr.onerror = function(e){
		params.error(this.responseText, e);
		// alert('Server Error!');
	};
	
	xhr.open(params.type,params.url);
	xhr.send();
}