UIActivityIndicatorView not working right - ios

Question

I have the following initialization in viewDidLoad:
self.indicator = [[UIActivityIndicatorView alloc]initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
[self.indicator setCenter:CGPointMake([[UIScreen mainScreen]bounds].size.width/2, [[UIScreen mainScreen]bounds].size.height/2)];
//self.indicator.hidden = YES;
[self.indicator setHidesWhenStopped:1];
self.indicator.color = [UIColor orangeColor];
self.indicator.autoresizingMask = UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleRightMargin | UIViewAutoresizingFlexibleTopMargin | UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleBottomMargin;
Now if I add the following 2 lines, the indicator shows and spins:
[self.view addSubview:self.indicator];
//self.indicator.hidden = NO;
[self.indicator startAnimating];
Thats not what I want, because the indicator should first show when I call my method, lets call it pressButton. I would then do the following:
- (void)pressButton {
[self.view addSubview:self.indicator];
[self.indicator startAnimating];
dispatch_async(dispatch_get_main_queue(), ^{
WebAccess *web = [WebAccess new];
NSDictionary *dicResults = [web logon:self.email.text :self.password.text];
if([[dicResults valueForKey:#"StatusCode"] intValue] == 200){// ALL IS OK
appDelegate.accessToken = [dicResults valueForKey:#"AccessToken"];
dicResults = [web getAccount:appDelegate.accessToken];
NSLog(#"dicResults after getaccount: %#", dicResults);
if([[dicResults valueForKey:#"StatusCode"] intValue] == 200){//dicResults holds a new object now!
NSArray *usersArray = [dicResults valueForKeyPath:#"Account.Users"];
NSLog(#"usersArray: %#", usersArray);//CORRECT DATA RECEIVED: YES
if(usersArray.count){
[[appDelegate cdh]deleteAllFromEntityWithName:#"AccountData"];
[[appDelegate cdh]deleteAllFromEntityWithName:#"UserData"];//------------- REMOVE ALL WHEN LOADING NEW USER. AMYBE TOO QF. CHECK WITH DESIGNER
}else{
UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:#"Error" message:#"No users found on this account!" delegate:nil cancelButtonTitle:#"OK" otherButtonTitles: nil];
[alertView show];
}
//more code........
appDelegate.users = [NSMutableArray arrayWithArray:[[appDelegate cdh] fetchUsers]];
if(appDelegate.users.count){
NSArray *currentUserArray = [NSArray arrayWithArray:[[appDelegate cdh]fetchCurrentUser]];
appDelegate.currentUser = [currentUserArray lastObject];
if(appDelegate.currentUser==nil)
appDelegate.currentUser = appDelegate.users[0];
}
[menu goToVC:1];
}
}else if([[dicResults valueForKey:#"StatusCode"] intValue] == 201){
UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:#"Error" message:#"Wrong email or password!" delegate:nil cancelButtonTitle:#"OK" otherButtonTitles: nil];
[alertView show];
}
[self.indicator stopAnimating];
});
}
I could've sworn I had it working yesterday when testing, but now it doesn't. Whats weird is if i put those same two lines from my press button method into viewdidload, the indicator shows, but when I do it inside my method (but obv outside the dispatch) it never shows....
Any help appreciated

Answer 1

Spin your long running process off onto its own thread. Leave the main thread open for UI updates.
- (void)pressButton
{
[self.view addSubview:self.indicator];
[self.indicator startAnimating];
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
// Code for your long running process to run in the background...
// Stop your activity indicator back on the main thread
dispatch_async(dispatch_get_main_queue(), ^{
[self.indicator stopAnimating];
});
});
}