UIImageView contentMode not working

[leancmscn]

    let imageView1 = UIImageView(image: UIImage(named: "goods.png"))
    imageView1.contentMode = .ScaleToFill
    imageView1.clipsToBounds = true
    imageView1.sizeToFit()

    contentContainerView.addArrangedSubview(imageView1)

    let imageView2 = UIImageView(image: UIImage(named: "goods.png"))
    imageView2.contentMode = .ScaleToFill
    imageView2.clipsToBounds = true
    imageView2.sizeToFit()
    contentContainerView.addArrangedSubview(imageView2)

contentMode not working