CODEWITHSUNDEEP
iosobjective-ccallbackselector
EnriMR
EnriMR

Reputation: 3970

I can't perform a selector from another file in iOS

I'm trying to implement my own API in iOS but I have one problem with callbacks.

I have implemented my callbacks with selectors but, when the function given is in another file/class, the app crashes.

This is the error:

2013-09-18 21:32:16.278 Vuqio[6498:19703] -[VuqioApi postCurrenProgramRequestDidEnd]: unrecognized selector sent to instance 0xa5a2150
2013-09-18 21:32:16.278 Vuqio[6498:19703] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[VuqioApi postCurrenProgramRequestDidEnd]: unrecognized selector sent to instance 0xa5a2150'

An this my code:

Call: (File Controller.m)

...
[self softCheckIn:@"922337065874264868506e30fda-1c2a-40a5-944e-1a2a13e95e95" inProgram:p.idProgram callback:@selector(postCurrenProgramRequestDidEnd)];
...
-(void)postCurrenProgramRequestDidEnd
{
    NSLog(@"Soft check-in");
}

- (void)softCheckIn:(NSString *)userId inProgram:(NSString *)program callback:(SEL)callback
{
    // Hacemos un soft checkin
    VuqioApi *api = [[VuqioApi alloc] init];
    NSMutableDictionary *data = [[NSMutableDictionary alloc] initWithObjectsAndKeys:
                                                userId, @"userId",
                                                program, @"programId",
                                                nil];
    [api postCurrentProgram:data withSuccess:callback andFailure:@selector(aaa)];
}

Methods: (File Api.m)

- (void)postCurrentProgram:(NSDictionary *)data withSuccess:(SEL)successCallback
{
    NSLog(@"Performing selector: %@", NSStringFromSelector(successCallback));
    
    [self postCurrentProgram:data withSuccess:successCallback andFailure:@selector(defaultFailureCallback)];
}
- (void) postCurrentProgram:(NSDictionary *)data withSuccess:(SEL)successCallback andFailure:(SEL)failureCallback {
    [self placePostRequest:@"api/programcurrent" withData:data withHandler:^(NSURLResponse *urlResponse, NSData *rawData, NSError *error) {
        
        NSLog(@"Performing selector: %@", NSStringFromSelector(successCallback));
        NSLog(@"Performing selector: %@", NSStringFromSelector(failureCallback));
        
        NSString *string = [[NSString alloc] initWithData:rawData encoding:NSUTF8StringEncoding];
        //NSDictionary *json = [NSJSONSerialization JSONObjectWithData:rawData options:0 error:nil];
        
        if ( ![string isEqual: @"ok"])
        {
            [self performSelector:failureCallback withObject:self];
        } else {
            NSLog(@"OK");
            [self performSelector:successCallback];
        }
    }];
}

- (void) defaultFailureCallback {
    NSLog(@"Failure");
}

Upvotes: 0

Views: 149

Answers (1)

Ben S
Ben S

Reputation: 69342

A selector is performed on an instance of a certain type. You need to pass the object that will have the selector messaged to it as well as the selector.

In the case above, you have a selector in Controller.m aaa which might be a valid method on an instance of Controller, but in the Api.m file, you're attempting to call the method aaa on an instance of Api, which results in a crash since that method isn't valid for that class.

Upvotes: 1

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