Mapping a JSON response to an object using RestKit and Objective-C

Question

I am relatively new to Objective-C and am attempting to use RestKit to receive a JSON response from a web service. I have successfully received the data back to my applicat

Answer 1

The snippet of your code seems a bit outdated. I strongly recommend reading the newest Object Mapping guide in order to leverage RestKit into it's fullest potential - especially the part Mapping without KVC.

Edit:

In order to post an object with RestKit and receive back an answer, we define a TranslationRequest class that will hold our request & Translation to hold our response.

Firstly, we set up our RKObjectManager and mappings (i usually do this in my AppDelegate):

RKObjectManager *manager = [RKObjectManager objectManagerWithBaseURL:kOurBaseUrl];
[manager setSerializationMIMEType:RKMIMETypeJSON];
//this is a singleton, but we keep the manager variable to avoid using [RKObjectManager sharedManager] all the time

//Here we define a mapping for the request. Note: We define it as a mapping from JSON to entity and use inverseMapping selector later.
RKObjectMapping *translationRequestMapping = [RKObjectMapping mappingForClass:[TranslationRequest class]];
[translationRequestMapping mapKeyPath:@"RegionTag" toAttribute:@"regionTag"];
...
[[manager mappingProvider] setSerializationMapping:[translationRequestMapping inverseMapping] forClass:[TranslationRequest class]];

//now we define the mapping for our response object
RKObjectMapping *translationMapping = [RKObjectMapping mappingForClass:[Translation class]];
[translationMapping mapKeyPath:@"id" toAttribute:@"identifier"];
[translationMapping mapKeyPath:@"Translation" toAttribute:@"translation"];
[[manager mappingProvider] addObjectMapping:mapping];

//finally, we route our TranslationRequest class to a given endpoint
[[manager router] routeClass:[TranslationRequest class] toResourcePath:kMyPostEndpoint];

This should be enough of the necessary setup. We can call our backend anywhere in the code (e.g. in any controller) like this:

//we create new TranslationRequest
TranslationRequest *request = [[TranslationRequest alloc] init];
[request setRegionTag:@"Hello"];
....
//then we fetch the desired mapping to map our response with
RKObjectMapping *responseMapping = [[RKObjectManager sharedManager].mappingProvider objectMappingForClass:class]
//and just call it. Be sure to let 'self' implement the required RKObjectManagerDelegate protocol
[[RKObjectManager sharedManager] postObject:request mapResponseWith:responseMapping delegate:self];]

Try this approach and let me know if you need any assistance.. I was not able to test it fully as i don't have any suitable backend that will return the responses, but judging from the RestKit log this should work.