ios - Modify behaviour of viewDidAppear in UIViewController -

i have application (uicatalog apple samples). using framework called lookback intended screen recording.

i have interface defined follows:

@interface aaplsteppperviewcontroller : uitableviewcontroller 

so in straight way subclass of uitableviewcontroller. , has implemented methods follows:

+ (nsstring*)lookbackidentifier {     return @"profile editor"; } 

i wanted investigate how lookbackidentifier being called , see that:

the question is: how introduce such behavior uitableviewcontroller system class , not able see source of calls numbered 1 , 2 @ stack?

as investigated framework docs, recommend implement that

- (void)viewdidappear:(bool)animated {     [super viewdidappear:animated];     ... } 

as me looks change inside uiviewcontroller - how achieve that?

i guess include playing uiviewcontroller - how? can't imagine how override single method of without subclasssing.

i have access aaplsteppperviewcontroller.

i grateful if give me push in right direction

as @dan pointed - swizzling right answer. tried instructions there: http://nshipster.com/method-swizzling/ , gave me desired behaviour.

thanks :)