iPhone - Google Directions API Response Problems - iphone

Question

I am using the Google Directions iOS API. I am getting the data using JSON instead of XML. But I am using AFNetworking to simplify this for me. AFNetworking is available at github. Right now, I am able to display an overlay route from one location to another on an MKMapView. Here is my code:
// AFNETWORKING ==========================================================
AFHTTPClient *_httpClient = [AFHTTPClient clientWithBaseURL:[NSURL URLWithString:#"http://maps.googleapis.com/"]];
[_httpClient registerHTTPOperationClass: [AFJSONRequestOperation class]];
[_httpClient setDefaultHeader:#"Accept" value:#"application/json"];
NSMutableDictionary *parameters = [[NSMutableDictionary alloc] init];
[parameters setObject:[NSString stringWithFormat:#"%f,%f", location.coordinate.latitude, location.coordinate.longitude] forKey:#"origin"];
[parameters setObject:[NSString stringWithFormat:#"%f,%f", location2.coordinate.latitude, location2.coordinate.longitude] forKey:#"destination"];
[parameters setObject:#"false" forKey:#"sensor"];
[parameters setObject:#"driving" forKey:#"mode"];
[parameters setObject:#"metric" forKey: #"units"];
NSMutableURLRequest *request = [_httpClient requestWithMethod:#"GET" path: #"maps/api/directions/json" parameters:parameters];
request.cachePolicy = NSURLRequestReloadIgnoringLocalCacheData;
AFHTTPRequestOperation *operation = [_httpClient HTTPRequestOperationWithRequest:request success:^(AFHTTPRequestOperation *operation, id responseObject) {
NSInteger statusCode = operation.response.statusCode;
if (statusCode == 200) {
[self parseResponse:responseObject];
} else {
}
} failure:^(AFHTTPRequestOperation *operation, NSError *error) { }];
[_httpClient enqueueHTTPRequestOperation:operation];
// ROUTE SETUP AND RESPONSE RECIEVED METHOD ==========================================================
- (void)parseResponse:(NSDictionary *)response {
NSArray *routes = [response objectForKey:#"routes"];
NSDictionary *routePath = [routes lastObject];
if (routePath) {
NSString *overviewPolyline = [[routePath objectForKey: #"overview_polyline"] objectForKey:#"points"];
NSLog(#"Status: %#", [response objectForKey: #"status"]);
NSLog(#"Legs: %#", [routePath objectForKey: #"legs[]"]);
_path = [self decodePolyLine:overviewPolyline];
NSInteger numberOfSteps = _path.count;
CLLocationCoordinate2D coordinates[numberOfSteps];
for (NSInteger index = 0; index < numberOfSteps; index++) {
CLLocation *location = [_path objectAtIndex:index];
CLLocationCoordinate2D coordinate = location.coordinate;
coordinates[index] = coordinate;
}
polyLine = [MKPolyline polylineWithCoordinates:coordinates count:numberOfSteps];
[self.mapView addOverlay:polyLine];
}
}
This is the main code to get the route functioning. And it works well! But now what I want to do is get direction list and complete duration and summary. So I took a deep look at Google Directions API Documentation and it tells me to use its different dictionaries and arrays and objects. But I have had no luck. I get a status of OK. When I log the count of the routes array, its only one object. Then the MOST important, legs[] array is NULL.
NSLog(#"Legs is: %#", [routePath objectForKey: #"legs[]"]);
Output:
Legs is (null)
Legs[] includes everything important like the direction list and duration. Summary is not NULL, it gives the name of one of the streets that the route bypasses. I dont know how that is a summary. Might be because there is only one object in the routes array. waypoint_order and warnings[] are NULL too. bounds and of course overview_polyline are valid, thats how I got the route working.
So whats the problem here? Why are so many of the objects Google Directions API provides NULL when I need them?
Thanks!

Answer 1

Alright, the problem was that the response for directions was taking too long. I expected the legs[] response to instantly deliver along with the overview_polyline. So I just had to wait till the response came in, this gives me an opportunity to insert a buffer UI.