Callback strong Reference Cycle

Question

Is the following creating a strong reference cycle? I have a feeling it is because I'm referencing self within callback.

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
    [picker dismissViewControllerAnimated:YES completion:^{
        UIImage *image = [self cropImageWithInfo:info];
        if (currentScreen == CurrentScreenApartment) {
            [self.profileViewModel.apartmentPhotos addObject:[RuntimePhoto runtimePhotoWithImage:image]];
        }
        else {
            [self.profileViewModel.userPhotos addObject:[RuntimePhoto runtimePhotoWithImage:image]];
        }
        dispatch_async(dispatch_get_main_queue(), ^{
            [self reloadPhotosCell];
        });
    }];
}

score 0 · Answer 1 · answered Apr 27 '18 at 02:03

You can use a weak variable of self:

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {

    typeof(self) __weak weakSelf = self;

    [picker dismissViewControllerAnimated:YES completion:^{
        UIImage *image = [weakSelf cropImageWithInfo:info];
        if (currentScreen == CurrentScreenApartment) {
            [weakSelf.profileViewModel.apartmentPhotos addObject:[RuntimePhoto runtimePhotoWithImage:image]];
        }
        else {
            [weakSelf.profileViewModel.userPhotos addObject:[RuntimePhoto runtimePhotoWithImage:image]];
        }
        dispatch_async(dispatch_get_main_queue(), ^{
            [weakSelf reloadPhotosCell];
        });
    }];
}

Callback strong Reference Cycle

1 Answers1