return data from sendAsynchronousReques - objective-c

Question

Objective c: I have a serviceClass connecting to a db with NSURLConnection and sendAsynchronousRequest.
I want to be able to use this class method and return the db-data to any other classmethod requesting it.
But since the sendAsynchronousRequest is returning void - how can i do this?
I cant get my head around it at all atm. Blocks? But how...
Please help
atm I am creating a user object directly in this codechunk bellow:
[NSURLConnection
sendAsynchronousRequest:urlRequest
queue:[[NSOperationQueue alloc] init]
completionHandler:^(NSURLResponse *urlResponse,
NSData *data,
NSError *error) {
if ([data length] > 0 && error == NULL){ // do success or error call with true or false
NSMutableData *incomingData;
if(!incomingData) {
incomingData = [[NSMutableData alloc]init];
}
[incomingData appendData:data];
NSString *string = [[NSString alloc]initWithData:incomingData
encoding:NSUTF8StringEncoding];
//incomingData = nil;
// create dictionary from json
NSData *jsondata = [NSData dataWithData:incomingData];
NSMutableDictionary *userDictionary = [NSJSONSerialization JSONObjectWithData:jsondata
options:NSJSONReadingMutableContainers
error:NULL];
// create user object
User *user = [User userFromDictionary:userDictionary];
NSLog(#"user back to object successfull!! %#", user);
}
}

Answer 1

You can use property for incomingData and then use that property to pass data to other methods/class.
#property (nonatomic, retain) NSMutableData * incomingData;
Now you can use self.incomingData to set value, and you need to return. You can use it in other methods, and when you need to pass this to other class, you can pass it.