Button width does not change in animation

I have a button whose width I want to shrink when pressed. However, the current method (and the method I saw online) doesn’t seem to work. Here’s how: @IBAction func addToOrderPressed(sender: AnyObject) { UIView.animateWithDuration(1.0, animations: { self.addToOrderButton.frame = CGRectMake( self.addToOrderButton.frame.origin.x, self.addToOrderButton.frame.origin.y, self.addToOrderButton.frame.size.width – 100, self.addToOrderButton.frame.size.height) }) self.addProductToCart(productAtIndex) println(“[Info] Product Added: (productAtIndex.title)”) println(“[Info] Cart Count: (self.dm.cartItems.count)”) […]