Retrieve latitude and longitude from parsed JSON file

I think you misunderstand a little bit, or maybe my question was confusing. I know JSON are parsed at string (most of the time). I added a image-link so you can see what the response I get back looks like. What I'm struggling with, is how to retrieve the lat and lng. When I look at the JSON file it goes something like "response" - "venues" - "location" - "lat" and lng". Meaning my line of code:

CLLocationCoordinate2DMake([location[@"lat"] doubleValue], [location[@"lng"] doubleValue]);

Won't work, but I don't know what to write instead.

First, try the code I gave you.

Tried this:

for (NSDictionary *venue in mainVC.venues) {
        NSDictionary *location = venue[@"location"];
        CLLocationCoordinate2D annotationCoordinate = CLLocationCoordinate2DMake([location[@"lat"] doubleValue], [location[@"lng"] doubleValue]);
        Annotations *annotation = [[Annotations alloc] init];
        annotation.coordinate = annotationCoordinate;

        [self.mapView addAnnotation:annotation];
    }

Ended up with with loong error:

2014-01-20 00:24:32.390 testApp[49745:70b] -[NSCFString objectForKeyedSubscript:]: unrecognized selector sent to instance 0x9f96f50 2014-01-20 00:24:32.393 testApp[49745:70b] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSCFString objectForKeyedSubscript:]: unrecognized selector sent to instance 0x9f96f50'

OK, that means your parser has unfolded the internal structure of the JSON and has essentially changed the hierarchy. To know the hierarchy, NSLog one of your dictionaries within your loop:

   for (NSDictionary * venue in mainVC.venues) {
       NSLog(@"%@", venue);
       abort(); // abort the program until we figure out what's going on.
   }

All the console gave me was:

2014-01-20 00:35:41.490 testApp[49905:70b] confident

But when I logged out the content of the loop in my main ViewController where I parse the JSON file i got:

2014-01-20 00:40:06.723 testApp[49989:70b] confident 2014-01-20 00:40:06.725 testApp[49989:70b] neighborhoods 2014-01-20 00:40:06.725 testApp[49989:70b] venues 2014-01-20 00:40:06.725 testApp[49989:70b] geocode

:)

Now I know what's going on. What you threw into mainVC.venues is actually the full response dictionary. Thus when you enumerate through it, it yields the keys instead. First, to fix the semantics, change the name of that property to responses. Next, your enumeration should look something like the following:

for ( NSDictionary * venue in mainVC.responses[@"venues"] ) {
    NSDictionary * location = venue[@"location"];
    //...
    // My guess is the coordinates are NSString. If that's the case, create an NSNumberFormatter object outside the loop
    // and use its numberFromString method
}

The is probably just me being tired but, I don't have a property in mainVC called responses? In MainViewController.m i have this line of code:

    self.venues = [dataDictionary objectForKey:@"response"];

and that's what I loop through in my mapViewController, so isn't

Objective-C
for ( NSDictionary * venue in mainVC.venues ) {
}

enough? Also I don't know If you saw it in my original post: heres is part of the JSON I'm working with: http://imgur.com/XHBUDwY

Be assured that I have read your original post in depth and have quite thorough understanding of what the structure of the JSON response. But also keep in mind that your parser is not exactly doing what you think it is doing, i.e. just looking at the HTTP JSON response without knowing the behavior of your parser is pointless.

To make it easier for you, just make the following two changes:

In your MainViewController:

    self.venues = dataDictionary[@"response"][@"venues"]; // This corrects a bug in your parser

Outside, in the loop you had:

    for (NSDictionary * venue in mainVC.venues) {
        NSDictionary * location = venue[@"location"];
        // ...
    }

Thank you so much! So simple mistake, maybe because I'm tired. Either way, again, Thanks!