Async call in Objective-C

Question

I'm trying to get data from a website- xml. Everything works fine.

But the UIButton remains pressed until the xml data is returned and thus if theres a problem with the internet service, it can't be corrected and the app is virtually unusable.

here are the calls:

{
    AppDelegate *appDelegate = (AppDelegate *)[[UIApplication sharedApplication] delegate];
    if(!appDelegate.XMLdataArray.count > 0){
        [UIApplication sharedApplication].networkActivityIndicatorVisible = YES;
        [appDelegate GetApps]; //function that retrieves data from Website and puts into the array - XMLdataArray.
    }
    XMLViewController *controller = [[XMLViewController alloc] initWithNibName:@"MedGearsApps" bundle:nil];
    [self.navigationController pushViewController:controller animated:YES];
    [controller release];
}

It works fine, but how can I make the view buttons functional with getting stuck. In other words, I just want the UIButton and other UIButtons to be functional whiles the thing works in the background.

I heard about performSelectorInMainThread but I can't put it to practice correctly.

Answer 1

Use NSURLConnection's connectionWithRequest:delegate: method. This will cause the specified request to be sent asynchronously. The delegate should respond to connection:didReceiveResponse: and will be sent that message once the response is completely received.