This document discusses modern iOS app architecture, including: 1. Using silent notifications instead of continuous polling for real-time apps. 2. Using asynchronous Core Data with separate contexts for writing and fetching to improve performance. 3. Embedding frameworks instead of static libraries to modularize code and allow dynamic loading on iOS 7 and above.

1. Modern iOS app
Architecture
Michał Tuszyński
iOS Developer, Schibsted Tech Polska

2. Agenda
1. Real time apps
2. Modern asynchronous Core Data
3. Embedded frameworks

3. What’s wrong?

4. What’s wrong?
func startPolling() {
let timer = NSTimer.scheduledTimerWithTimeInterval(1, target:
self, selector: "update:", userInfo: nil, repeats: true)
NSRunLoop.currentRunLoop().addTimer(timer, forMode:
NSDefaultRunLoopMode)
}
@objc func update(timer: NSTimer) {
let request = NSURLRequest(URL: NSURL(string: "https://
myawsomeapp.com/get_something")!)
let task = session.dataTaskWithRequest(request,
completionHandler: handler)
task.resume()
}

5. What’s wrong?
Continuous polling is (usually) bad.

6. What’s wrong?
Alternative?

7. What’s wrong?
Silent Notifications!

8. {
"aps": {
"content-available": 1,
"sound": ""
},
"object": {
"value": "test"
}
}
Silent Notifications!

9. func application(application: UIApplication,
didReceiveRemoteNotification
userInfo: [NSObject : AnyObject],
fetchCompletionHandler handler:
(UIBackgroundFetchResult) -> Void)
Silent Notifications!

10. Background fetch
Silent Notifications!

11. Background fetch
func application(application: UIApplication,
performFetchWithCompletionHandler
completionHandler: (UIBackgroundFetchResult) ->
Void)

12. Realtime app demo
http://pushtest.srgtuszy.com

13. What’s wrong?
let context = NSManagedObjectContext()
context.persistentStoreCoordinator =
persistentStore

14. What’s wrong?
Thread confinement is obsolete and left for backwards
compatibility

15. What’s wrong?
Parent-child contexts are the way to go

16. Asynchronous Core Data?

17. Asynchronous Core Data?
- Separate context for writing to persistent store
- NSAsynchronousFetchRequest
- NSBatchUpdateFetchRequest

18. Embedded Frameworks

19. Frameworks vs static libraries

20. Choosing the right option

21. Use dlopen() on iOS 7

22. if (SystemVersionGreaterOrEqual(@"8.0")) {
NSString *frameworkPath = [[NSBundle mainBundle]
pathForResource:@"HockeySDK" ofType:@"framework"];
NSString *libraryPath = [frameworkPath
stringByAppendingPathComponent:@"HockeySDK"];
void *handle = dlopen([libraryPath
cStringUsingEncoding:NSUTF8StringEncoding], RTLD_LAZY);
if (handle == NULL) {
NSString *error = [NSString
stringWithUTF8String:dlerror()];
NSLog(@"dlopen failed: %@", error);
return;
}
id hockeyManager =
[[NSClassFromString(@"BITAuthenticator") alloc] init];
dlclose(handle);
}

23. Wrap up

24. Thank you!