Put UIAlertView above UIActivityIndicatorView - objective-c

Question

I want to see in a moment my UIAlert above my UIActivityIndicatorView, i have this code:
- (void)showWithLabelDeterminate{
HUD = [[MBProgressHUD alloc] initWithView:self.navigationController.view];
[self.navigationController.view addSubview:HUD];
// Set determinate mode
HUD.mode = MBProgressHUDModeDeterminate;
HUD.delegate = self;
HUD.labelText = #"Loading";
// myProgressTask uses the HUD instance to update progress
[HUD showWhileExecuting:#selector(myProgressTask) onTarget:self withObject:nil animated:YES];
}
- (void)myProgressTask
{
float progress = 0.0f;
while (progress < 0.99f)
{
progress += 0.01f;
HUD.progress = progress;
usleep(50000);
if(progress > 0.02f & progress < 0.05f)
{
NSString * string = [NSString stringWithFormat:#"http://localhost:8080/......"];
NSURL *url = [NSURL URLWithString:string];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url
cachePolicy:NSURLRequestUseProtocolCachePolicy
timeoutInterval:60.0];
urlData = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];
if(!urlData)
{
[self simpleAlert];
}
else
{
datos = [[NSMutableString alloc]initWithData:urlData encoding:NSISOLatin1StringEncoding];
}
}
}
}
-(void)simpleAlert
{
UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:#"Dont connect!!" delegate:self cancelButtonTitle:#"Refresh" otherButtonTitles:nil];
[alertView show];
[alertView release];
}
The problem is that i dont see my UIAlertView above my UIActivityIndicatorView.....

Answer 1

myProgressTask is either executing on a background thread or is blocking the main thread with its calls to usleep.
If it's on a background thread then your use of UIAlertView is invalid because UIKit is, in the general case, usable from the main thread only. The quickest solution would be to use performSelectorOnMainThread:... to call simpleAlert.
If it's on the main thread then you're probably blocking UIKit from operating. Obvious comments would follow about using a non-blocking NSURLConnection and using NSTimer or performSelector:withObject:afterDelay: to schedule things to happen after a pause.