iOS登录过程适用于模拟器，但不适用于iPhone（3GS）

Question

我为我开发的iPhone应用程序创建了一个登录过程，登录过程在Xcode的iOS模拟器应用程序中工作，但不适用于我的实际电话。在登录过程中的代码是：

- (IBAction)processLogin:(id)sender { 

// hide keyboard 
[_textFieldUsername resignFirstResponder]; 
[_textFieldPin resignFirstResponder]; 


// First - make activity indicator visible, then start animating, then turn of wrong user/pin label 
_welcomeActivityIndicator.hidden = FALSE; 
[_welcomeActivityIndicator startAnimating]; 
[_wrongUserPin setHidden:YES]; 

// check if username and pin text fields are populated 
if ([_textFieldUsername.text length ] == 0 && [_textFieldPin.text length ] == 0) 
{ 
    [_welcomeActivityIndicator stopAnimating]; 
    [_wrongUserPin setHidden:NO]; 
} 

// CORE DATA 
NSFetchRequest *request = [[NSFetchRequest alloc] init]; 
NSEntityDescription *entity = [NSEntityDescription entityForName:@"Account" inManagedObjectContext:_managedObjectContext]; 

// set entity for request 
[request setEntity:entity]; 

// filter results using a predicate 
NSPredicate *pred =[NSPredicate predicateWithFormat:(@"username = %@"), _textFieldUsername.text]; 

// set predicate for the request 
[request setPredicate:pred]; 

NSError *error = nil; 

// store DB usernames in results array 
NSArray *results = [_managedObjectContext executeFetchRequest:request error:&error]; 

NSLog(@"The returned results are %@",results); 


// check text field against results stored in DB 
for (Account *anAccount in results) { 
    if ([anAccount.username isEqualToString:_textFieldUsername.text]){ 
     NSLog(@"Your username exists"); 
     if ([anAccount.password isEqualToString:_textFieldPin.text]){ 
      NSLog(@"Your pin is correct"); 

      // TODO - put this in proper place - play audio bell if user logs in correctly 
      CFBundleRef mainBundle = CFBundleGetMainBundle(); 
      CFURLRef soundFileURLRef; 
      soundFileURLRef = CFBundleCopyResourceURL(mainBundle, (CFStringRef) @"Glass", CFSTR("aiff"), NULL); 
      UInt32 soundID; 
      AudioServicesCreateSystemSoundID(soundFileURLRef, &soundID); 
      AudioServicesPlaySystemSound(soundID); 

      // TODO - put this in proper place - Load ViewController(Root)Home 
      if([anAccount.username isEqualToString:@"root"]) 
      { 
       UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil]; 
       ViewControllerRootHome *roothome = (ViewControllerRootHome *)[storyboard instantiateViewControllerWithIdentifier:@"rootHome"]; 
       [self presentModalViewController:roothome animated:YES]; 
      } 
      else { 
       UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil]; 
       ViewControllerHome *home = (ViewControllerHome *)[storyboard instantiateViewControllerWithIdentifier:@"Home"]; 
       [self presentModalViewController:home animated:YES]; 
      } 
     } 
     else { 
      NSLog(@"Your pin is wrong"); 
      [_welcomeActivityIndicator stopAnimating]; 
      [_wrongUserPin setHidden:NO]; 
      } 
     } 
    else { 
     NSLog(@"Your username was not found"); 
     [_welcomeActivityIndicator stopAnimating]; 
     [_wrongUserPin setHidden:NO]; 
     } 
    } 

} 

我存储在核心数据DB的用户名，并存储在钥匙串针。我能够创建在iPhone上的帐户和信息现场表明，有在iPhone上创建的帐户，但是当我尝试登录我看到的是用户名或密码是错误的

可以将项目从这里下载https://github.com/ipatch/KegCop/zipball/master

Answer 1

我不确定是什么解决了这个问题，但是在完成following tutorial后，登录过程再次运行。

Answer 2

它看起来不像你在这个代码中的任何地方存储用户名/密码到CoreData。你确定你的默认数据库中有条目吗？