Dynamic refresh in a view - xcode 4 / interface builder

I'm new to xcode so please bear with me.

I have a label that I have set to blank, and after a user clicks 'go' I generate a random word or number and use:

self.label.stringValue = "some_word"

to update the view. (I am using MacRuby btw)

However, I would like to show 20 or so random words in quick succession before the last one is shown - just because it's too boring at the moment. (Alternatively, I'd be happy with showing an animated graphic in its place - which is replaced by the final random word.)

I've tried things like:

100开发者_开发知识库.times do
 num = rand(40)
 self.label.stringValue = num
end

But it doesn't work. I've also tried .reloadData but to no avail as well.

Any ideas on how to achieve this?

---

So as not to leave the question haning, from the Macruby mailing list:

def drawWord(sender)
if !next_word
 self.timer.invalidate
 return
end
self.label.stringValue = next_word
self.setNeedsDisplay true
end

def next_word
...
end

self.timer = NSTimer.scheduledTimerWithTimeInterval( 1/20.0,
target:self, selector:"drawWord:", userInfo:nil, repeats:true)