I believe the issue is due to the use of sendSynchronousRequest:returningResponse:error:
This method will be blocking the main/UI thread so the HUD never actually gets a chance to show until the method has returned, at which point the code continues and the HUD is hidden.
I think you should be looking at using an asynchronous request. and implementing the NSURLConnection
delegate methods.
EDIT: Added code sample.
Assuming you're targeting iOS 5 and higher you can use the following code snippet which takes advantage of blocks with sendAsynchronousRequest:queue:completionHandler: and GCD.
NSOperationQueue *backgroundQueue = [[NSOperationQueue alloc] init];
[NSURLConnection sendAsynchronousRequest:request
queue:backgroundQueue
completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
// NOTE: This block is called on the background queue.
// Use GCD to get back onto the main thread
dispatch_async(dispatch_get_main_queue(), ^{
// This block will process the response and data on the main thread
});
}];
It really is very little work to port your existing code to use this mechanism. If you don't know how blocks work you should read the documentation as they are a very powerful language feature and are being used in an increasing amount of Apple and third-party frameworks.
I would also recommend staying AWAY from third-party networking libraries for now until you understand the nuances that can cause issues such as this.