title: Save UITextField everytime user scroll
body: <p>My issue is, i have 5 UIViewController that i put all in one UIScrollView. In each viewcontroller i have some UITextField that i need the text to be saved to NSUserDefaults.
  I'm able to do it using button, but how do i save it everytime the user scroll to next view?(without any button?)
  Thanks..
  This is the working code i'm using for the first viewcontroller </p>
  
  <pre><code>- (void)save:(id)sender {
      NSString *a_name1 = [name text];
      NSString *a_address = [address text];
      NSString *a_address2 = [address2 text];
      NSString *a_age = [age text]
  
      NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
      [defaults setObject:a_name1 forKey:@"name"];
      [defaults setObject:a_address forKey:@"address"];
      [defaults setObject:a_address2 forKey:@"address2"];
      [defaults setObject:a_age forKey:@"age"];
      [defaults synchronize];
  }
  </code></pre>