iOS - MBProgressHUD - JSON Asynch call - Application Delegate

Question

i'm creating an application that have some Json calls. For this purpose i have created a new method in application delegate class that do these calls. This method is called from different view controller of my application. I would like use the MBProgressHUD during every call. So i have used an asynch call to retrieve Json data and use MBProgressHUD.

1. Show MBProgressHUD
2. Do Asynch NSURLConnection Call
3. Fetch Data (and Hide MBProgressHUD)
4. Do others operations.

The problem is that on step 4 the Json response is empty. There is a way to test if the step 2 and 3 is finished?

I have to use asynch call because i'm using MBProgressHUD.

 [MBProgressHUD showHUDAddedTo:view animated:YES];
    dispatch_async(dispatch_get_global_queue( DISPATCH_QUEUE_PRIORITY_LOW, 0), ^{
        NSData* data = [NSData dataWithContentsOfURL:[NSURL URLWithString:linkChiamata]];
        // NSData* data;
        NSArray* json;
        json = [NSJSONSerialization JSONObjectWithData:data options:kNilOptions error:nil];
        jsonResponse = [json objectAtIndex:0];

        dispatch_async(dispatch_get_main_queue(), ^{
            [MBProgressHUD hideHUDForView:view animated:YES];
        });
    });


    //Esito chiamata JSON
    int esitoChiamata;
    esitoChiamata = [[jsonResponse objectForKey:@"codice"] intValue];

jsonResponse is empty for all calls.

Thanks in advance.

Answer 1

You need to wait until NSURLConnection delegate success/fail method is called before you do other operations.

Can you provide more info on how you do the NSURLConnection call? Here's one way to do it.

Answer 2

I think there is two possibilities.

• You can use NSCondition to block a thread and wait for condition before to continue. A simple example is here and easy to adapt to your solution.
• Create a function running in background with a complexion block. See my answer here

Hope it will help you.