我尝试以编程方式使用自动布局，使我的自定义视图在边界更改时调整其大小。我想达到的目标是：
1)使视图在屏幕上尽可能大，但保持其高度和大小之间的纵横比为8/5
2)永远不要离开安全区
3)总是站在中间
当我在故事板中使用这组约束时，一切都很完美，但是当我在代码中做同样的事情时，xcode打破了我的高度约束（我使用它来控制视图的长宽比）。我按轻重缓急行事，但没有成功。我做错了什么？下面是我的代码和故事板约束的屏幕截图：
screenshot of storyboard constraints

private func setupLayout () {

    playingCardView.translatesAutoresizingMaskIntoConstraints = false

    //makes the maxim width possible
    let playingCardViewWidthConstraint = playingCardView.widthAnchor.constraint(equalToConstant: 800)
    playingCardViewWidthConstraint.priority = UILayoutPriority(rawValue: 250)
    playingCardViewWidthConstraint.identifier = "width"

    //for aspect ratio
    let playingCardViewHeightConstraint = playingCardView.heightAnchor.constraint(equalTo: playingCardView.widthAnchor, multiplier: 8.0/5.0)
    playingCardViewHeightConstraint.identifier = "height"

    //make the view stay within bounds
    //add some padding top
    let playingCardTopConstraint = playingCardView.topAnchor.constraint(lessThanOrEqualTo: view.safeAreaLayoutGuide.topAnchor, constant: Constants.offsetFromTheEdge)

    //add some padding bottom
    let plaingCardViewBottomConstraint = playingCardView.bottomAnchor.constraint(lessThanOrEqualTo: view.safeAreaLayoutGuide.bottomAnchor, constant: Constants.offsetFromTheEdge)

    //add some padding leading
    let playingCardViewLeadingConstraint = playingCardView.leadingAnchor.constraint(lessThanOrEqualTo: view.layoutMarginsGuide.leadingAnchor, constant: Constants.offsetFromTheEdge)

    ////add some padding trailing
    let playingCardViewTrailingConstraint = playingCardView.trailingAnchor.constraint(lessThanOrEqualTo: view.layoutMarginsGuide.trailingAnchor, constant: Constants.offsetFromTheEdge)

    NSLayoutConstraint.activate([
        playingCardViewWidthConstraint,
        playingCardViewHeightConstraint,
        playingCardView.centerXAnchor.constraint(equalTo: view.centerXAnchor),
        playingCardView.centerYAnchor.constraint(equalTo: view.centerYAnchor),
        playingCardTopConstraint,
        playingCardViewBottomConstraint,
        playingCardViewLeadingConstraint,
        playingCardViewTrailingConstraint
            ])
    }
}