title: Iphone : unrecognized selector sent to instance & viewDidLoad isn't running
body: <p>I'm developing an application.
  I used a TabBar and every tab have its Class (FirstViewController, SecondViewController, ... )
  There is one AppDelegate too.</p>
  
  <p>When I launch the program, the first Class is running.
  When i select the second tab, the <code>Secondview</code>.xib 's running but the "<code>viewDidLoad</code>" isn't working.
  When I select the third Tab, that's the same.</p>
  
  <p>I've put some buttons on the third tab, and when I push it, I have a </p>
  
  <pre><code> &gt; -[UIViewController testAuthentication:]: unrecognized selector sent to instance 0x5f16920
      2011-04-08 13:46:42.511 e-mars[19501:207] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UIViewController testAuthentication:]: unrecognized selector sent to instance 0x5f16920'
  </code></pre>
  
  <p>Here's the code of my classes</p>
  
  <p><strong>SecondViewController.h</strong></p>
  
  <pre><code>#import &lt;UIKit/UIKit.h&gt;
  @interface SecondViewController : UIViewController {
  }
  @end
  </code></pre>
  
  <p><strong>SecondViewController.m</strong></p>
  
  <pre><code>#import "SecondViewController.h"
  @implementation SecondViewController
  - (void)viewDidLoad {
      [super viewDidLoad];
  NSLog(@"viewDidLoad de SecondViewController");
  
  NSURL *url = [NSURL URLWithString: @"http://iosdevelopertips.com/images/logo-iphone-dev-tips.png"];
  UIImage *image = [UIImage imageWithData: [NSData dataWithContentsOfURL:url]]; 
  
  [self.view addSubview:[[UIImageView alloc] initWithImage:image]];
  }
  
  - (void)dealloc {
      [super dealloc];
  }
  
  @end
  </code></pre>
  
  <p><strong>ThirdViewController.h</strong></p>
  
  <pre><code>#import &lt;UIKit/UIKit.h&gt;
  
  @interface ThirdViewController : UIViewController {
  IBOutlet UITextField *login;
  IBOutlet UITextField *motdepasse;
  NSMutableData *responseData;
  }
  @property (retain, nonatomic) UITextField *login;
  @property (retain, nonatomic) UITextField *motdepasse;
  @property (retain, nonatomic) NSMutableData *responseData;
  - (IBAction) testAuthentication: (id)sender;
  - (IBAction) saveAuthentication: (id)sender;
  @end
  </code></pre>
  
  <p><strong>ThirdViewController.m</strong></p>
  
  <pre><code>#import "ThirdViewController.h"
  
  @implementation ThirdViewController
  
  @synthesize login;
  @synthesize motdepasse;
  @synthesize responseData;
  
  - (id)initWithFrame:(CGRect)frame {
      //if ((self = [super initWithFrame:frame])) {
          // Initialization code
      //}
      return self;
  }
  
  -(IBAction) testAuthentication: (id)sender {
      //NSLog(@"testAuthentication");
  }
  
  
  - (IBAction) saveAuthentication: (id)sender {
      NSLog(@"saveAuthentication");
  }
  - (void)dealloc {
      [login dealloc];
      [motdepasse dealloc];
      [responseData dealloc];
      [super dealloc];
  }
  @end
  </code></pre>