I have a `UIButton` in my app that I call "buttonPlay". I am using AutoLayout but the button doesn't have any `NSLayoutConstraints` attached to it.

I would like to code an animation **to increase and the decrease the height and the width** of the button. Here's how the animation code looks like:

```
    // "Repeat" because the animation must repeat itself
    UIView.animateWithDuration(1.0, delay: 0.6, options: UIViewAnimationOptions.Repeat, animations: {
        // Animation code goes here
        // nil: the animation is not supposed to end
        }, completion: nil)
}

```

To get the **original values of the x position, y position, width and height** I am using the following code: 

```
var frmPlay : CGRect = self.buttonPlay.frame

// get the current x and y positions
        let originXbutton = frmPlay.origin.x
        let originYbutton = frmPlay.origin.y

// get the current width and height of the button     
        let originWidthbutton = frmPlay.size.width
        let originHeightbutton = frmPlay.size.height

// set the frame (frmPlay) to the button frame
        self.buttonPlay.frame = frmPlay

```

Okay, it's now time to increase or decrease the width and the height of the animation. I'll put this code inside the `animation` block:

```
        self.buttonPlay.frame = CGRectMake(
            originXbutton,
            originYbutton,
            originWidthbutton-100,
            originHeightbutton)

        self.buttonPlay.frame = CGRectMake(
            originXbutton,
            originYbutton,
            originWidthbutton+100,
            originHeightbutton)

```

The animation code will look something like this:

```
    UIView.animateWithDuration(1.0, delay: 0.6, options: UIViewAnimationOptions.Repeat, animations: {

        println("Animation function animateStuff() started!")

        var frmPlay : CGRect = self.buttonPlay.frame

        let originXbutton = frmPlay.origin.x
        let originYbutton = frmPlay.origin.y

        let originWidthbutton = frmPlay.size.width
        let originHeightbutton = frmPlay.size.height

        self.buttonPlay.frame = frmPlay

        self.buttonPlay.frame = CGRectMake(
            originXbutton,
            originYbutton,
            originWidthbutton-100,
            originHeightbutton)

        self.buttonPlay.frame = CGRectMake(
            originXbutton,
            originYbutton,
            originWidthbutton+100,
            originHeightbutton)

        }, completion: nil)

```

Let's run the app. Uh oh! The button (also called buttonPlay) **doesn't get bigger or smaller in any way**. Though it moves from right to left. But hey! I haven't touched the x and the y positions code.

What causes it?