MWFeedParser check if data is new - ios

Question

I'm currently trying to make a RSS like iPhone application using MWFeedParser https://github.com/mwaterfall/MWFeedParser to parse my xml feed. Currently I'm trying to implement a background fetch into my app. When there are new items the user gets a local notification. I'm having a hard time checking if there are new entries in my RSS feed I'm currently using the code below. parsedItems is an NSArray which is automatically filled when [feedparser parse] is called. Now the problem is that parsedItems.count always returns zero although I refresh my feed. Any ideas?
In my app delegate I have the following function:
-(void)application:(UIApplication *)application performFetchWithCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler{
NewsTableViewController *viewController = [[NewsTableViewController alloc] init];
[viewController fetchNewDataWithCompletionHandler:^(UIBackgroundFetchResult result) {
completionHandler(result);
}];
}
And in my NewsTableViewController class I have the function:
-(void)fetchNewDataWithCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler {
NSArray *oldItems;
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSData *objectData = [defaults objectForKey:#"parsedItems"];
if(objectData != nil)
{
oldItems = [NSKeyedUnarchiver unarchiveObjectWithData:objectData];
oldItems = [oldItems sortedArrayUsingDescriptors:
[NSArray arrayWithObject:[[NSSortDescriptor alloc] initWithKey:#"date"
ascending:NO]]];
}
// Refresh data
[feedParser stopParsing];
[parsedItems removeAllObjects];
[feedParser parse];
NSLog(#"old:%lu", oldItems.count);
NSLog(#"new:%lu", parsedItems.count);
NSLog(#"ding:%lu", self.itemsToDisplay.count);
if (parsedItems.count == oldItems.count) {
completionHandler(UIBackgroundFetchResultNoData);
NSLog(#"No data.");
}
else {
[UIApplication sharedApplication].applicationIconBadgeNumber++;
[self sendNotification];
completionHandler(UIBackgroundFetchResultNewData);
[defaults setObject:[NSKeyedArchiver archivedDataWithRootObject:parsedItems] forKey:#"parsedItems"];
[defaults synchronize];
NSLog(#"New data was fetched.");
}
}