Assign NSArray from a ViewController to go through a client - ios

Question

I have a NSArray in my ViewController called tweets. To retrieve the tweets I have to use a method in my TwitterClient.m class. The method is shown below:
-(NSArray*)getTimeline {
NSArray *timelineArray;
[self.twitterClient registerHTTPOperationClass:[AFJSONRequestOperation class]];
[self.twitterClient getPath:#"1.1/statuses/user_timeline.json" parameters:nil success:^(AFHTTPRequestOperation *operation, id responseObject) {
NSArray *responseArray = (NSArray *)responseObject;
[responseArray enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
NSLog(#"Success: %#", obj);
}];
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(#"Error: %#", error);
}];
return responseArray;
}
However as you know you cant return the responseArray because it is inside a block. What would be a more efficient way to do this.
I have another way but in this method I cannot assign the response array as the NSArray that is the parameter:
-(void)getTimeline:(NSArray*)tweetArray {
[self.twitterClient registerHTTPOperationClass:[AFJSONRequestOperation class]];
[self.twitterClient getPath:#"1.1/statuses/user_timeline.json" parameters:nil success:^(AFHTTPRequestOperation *operation, id responseObject) {
NSArray *responseArray = (NSArray *)responseObject;
[responseArray enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
NSLog(#"Success: %#", obj);
responseArray = tweetArray;
}];
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(#"Error: %#", error);
}];
}
Basically the final question is how do I assign the tweets array in my View Controller to equal the response array that comes in through the TwitterClient class.

Answer 1

You should pass a block that is getting called after you are done getting your required information:
- (void)getTimelineWithCompletionBlock:(void (^)(NSError *err, NSArray *arr)) block {
[self.twitterClient registerHTTPOperationClass:[AFJSONRequestOperation class]];
[self.twitterClient getPath:#"1.1/statuses/user_timeline.json" parameters:nil success:^(AFHTTPRequestOperation *operation, id responseObject) {
(block ? block(nil, responseObject) : nil);
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
(block ? block(error, nil) : nil);
}];
}
You can call the method the following way:
[self getTimelineWithCompletionBlock:^(NSError *err, NSArray *arr) {
}];
Inside the completion block you have the data available and you can update your UI or whatever you intend to do. Depending on the implementation of getPath, you maybe have to dispatch the completion block on the main queue, because you are just allowed to update UI on the main thread.