SBJson displays null - ios

Question

I am trying to parse some json data with SBJson to show the current temperature. The example code from this tutorial works perfect: Tutorial: Fetch and parse JSON
When I change the code to my json feed i get a null. I am kind of new to JSON but followed every tutorial and documentation I found. The json source i used: JSON Source
My code with sbjson:
NSString *responseString = [[NSString alloc] initWithData:responseData encoding:NSUTF8StringEncoding];
self.responseData = nil;
NSArray* currentw = [(NSDictionary*)[responseString JSONValue] objectForKey:#"current_weather"];
//choose a random loan
NSDictionary* weathernow = [currentw objectAtIndex:0];
//fetch the data
NSNumber* tempc = [weathernow objectForKey:#"temp_C"];
NSNumber* weatherCode = [weathernow objectForKey:#"weatherCode"];
NSLog(#"%# %#", tempc, weatherCode);
and of course I have already implemented the other sbjson code.

Answer 1

There is no current_weather key in the JSON data you posted. The structure is:
{ "data": { "current_condition": [ { ..., "temp_C": "7", ... } ], ... } }
Here's a visual representation:
Therefore, to get to temp_C, you'd need to first obtain the top-level data property:
NSDictionary* json = (NSDictionary*)[responseString JSONValue];
NSDictionary* data = [json objectForKey:#"data"];
then, from that, obtain the current_location property:
NSArray* current_condition = [data objectForKey:#"current_condition"];
and finally, from the current_location array, get the element you're interested in:
NSDictionary* weathernow = [current_condition objectAtIndex:0];
Also note that temp_C and weatherCode are strings, not numbers. To transform them to numbers, instead of:
NSNumber* tempc = [weathernow objectForKey:#"temp_C"];
NSNumber* weatherCode = [weathernow objectForKey:#"weatherCode"];
you could use something like:
int tempc = [[weathernow objectForKey:#"temp_C"] intValue];
int weatherCode = [[weathernow objectForKey:#"weatherCode"] intValue];
(or floatValue / doubleValue if the value is not supposed to be an int, but rather a float or a double)
You would then use %d (or %f for float / double) as a format string:
NSLog(#"%d %d", tempc, weatherCode);

Answer 2

Provided link returns json without current_weather parameter. There is only current_condition parameter, please review this.

Answer 3

Use NSJSONSerialization instead of JSONValue.
NSData* data = [responseString dataUsingEncoding:NSUTF8StringEncoding];
NSDictionary* jsonDict = [NSJSONSerialization
JSONObjectWithData:data
options:kNilOptions
error:&error];
NSLog(#"jsonDict:%#",jsonDict);
In your link, there is no current_weather key.
NSString* tempc = [[[[jsonDict objectForKey:#"data"] objectForKey:#"current_condition"] objectAtIndex:0] objectForKey:#"temp_C"];