code within continueWithBlock executed but result is not immediate [duplicate] - objective-c

Question

When running this code...
-(IBAction)loginWithTwitter:(id)sender {
NSLog(#"Logging in with twitter");
ACAccountStore *accountStore = [[ACAccountStore alloc]init];
ACAccountType *accountType = [accountStore accountTypeWithAccountTypeIdentifier:ACAccountTypeIdentifierTwitter];
[accountStore requestAccessToAccountsWithType:accountType options:nil completion:^(BOOL granted, NSError *error) {
if (error) {
[self showError:error];
return;
}
if (granted) {
NSArray *accountsArray = [accountStore accountsWithAccountType:accountType];
if ([accountsArray count] > 1) {
NSLog(#"Multiple twitter accounts");
}
ACAccount *twitterAccount = [accountsArray objectAtIndex:0];
NSLog(#"%#", twitterAccount);
[self pushMainController];
}
}];
}
There is a 5-10 second delay before the pushMainControlleris actually called, even though the account information is logged almost immediately (after pre-authorization). If I move the pushMainController call after the block however, it happens immediately, the only problem being that a user isn't necessarily logged in at that point. I understand that it can take a second for a block to have a response due to variables such as network connectivity, but can someone help me understand this?

Answer 1

The completion block is not being done on the main queue. You need to ensure your UI code gets done on the main thread:
[accountStore requestAccessToAccountsWithType:accountType options:nil completion:^(BOOL granted, NSError *error) {
if (error) {
[self showError:error];
return;
}
if (granted) {
NSArray *accountsArray = [accountStore accountsWithAccountType:accountType];
if ([accountsArray count] > 1) {
NSLog(#"Multiple twitter accounts");
}
ACAccount *twitterAccount = [accountsArray objectAtIndex:0];
NSLog(#"%#", twitterAccount);
dispatch_async(dispatch_get_main_queue(), ^{
[self pushMainController];
});
}
}];
You may have to wrap the showError call as well.