title: AddObserver UIKeyboardWillShowNotification trouble specifying object
body: <p>I'm trying to receive notification when the keyboard appears but I'm in a situation where I have 2 UITextViews and need to be able to differentiate between them. For some reason, I can't figure out how to filter this using the object parameter of "addObserver". I've got something like this:</p>
  
  <pre><code> UITextView* w = mSubview.mText;
   NSNotificationCenter* dnc = [NSNotificationCenter defaultCenter];
   [dnc addObserver:self selector:@selector(showNotesKeyboard:)  name:UIKeyboardWillShowNotification object:w ];
  </code></pre>
  
  <p>Whenever I specify <code>w</code> I don't enter <code>showNotesKeyboard</code>. Only when I pass in <code>nil</code> does the notification actually get picked up. There must be something I'm missing here, please help me out.
  Thanks!</p>