Relational objects in Objective C

Question

I have two classes that define Video and Cue objects. I get my data through an JSON API. The backend is written in Rails and has a one-to-many relationship between Video and Cues.

The data I get is structured like this:

{ "true":
  [
      {
        "id" : 3,
        "title" : "My Title"
        [
            { "cues":
              [
                  {
                      "id": 117,
                      "time" : "12.81",
                      "video_id" : 3
                  },
                  {
                      "id": 118,
                      "time" : "14.34",
                      "video_id" : 3
                  }
              ]
            }
        ]
    }
  ]
}

I have a method in Video.m that gets the JSON array, puts it in a dictionary and converts the dictionary to an array of Video objects.

+(id) getVideos {
    NSURL *videoURL = [NSURL URLWithString:@"http://localhost:3000/myEndPoint"];
    NSData *jsonData = [NSData dataWithContentsOfURL:videoURL];
    NSError *error = nil;
    NSDictionary *videoDictionary = [NSJSONSerialization JSONObjectWithData:jsonData options:0 error:&error];

    NSMutableArray *videos = [NSMutableArray array];

    for (NSDictionary *dict in videoDictionary[@"true"]) {
        NSString *title = [dict objectForKey:@"title"];
        Video *newVideo = [[Video alloc] initWithTitle:title];
        [videos addObject: newVideo];
    }

    return videos;

}

How should I format the cues so that I can get specific cues from a Video, like in a relational sort of way if possible, if not then just the best practise. In Rails it would be video.cues. Can I do this in Objective C?

Would be perfect if I could end up having the ability to do something like:

Cue *currentCue = video.cues[0];

Answer 1

Add a property to your Video class: NSArray *cues. And change your init method to initWithTitle:(NSString*)title andCues:(NSArray*)cues. That way you'll be able to do exactly that: video.cues[0]