在 swift 中旋转或捏合后使按钮位于视图的右侧

Question

图像编辑应用程序。 它可以使用 pinchGesture 缩放图像，使用 rotateGesture 旋转图像并从角落拖动以调整图像大小。 图像附近有 2 个按钮。 一个旋转按钮——这个按钮触发图像的旋转，还有一个删除图像按钮。
现在，当我捏合或旋转按钮时，按钮不再位于图像的右侧。 约束正在被打破。 这是它在破坏约束的情况下的样子：

这是如果一切正常

private let imageView: UIImageView = {
        let imageView = UIImageView()
        let bundlePath = Bundle.main.path(forResource: "lockscreen", ofType: "jpeg")
        imageView.translatesAutoresizingMaskIntoConstraints = false
        imageView.image = UIImage(contentsOfFile: bundlePath ?? "")
        imageView.isUserInteractionEnabled = true
        imageView.contentMode = .scaleToFill
        imageView.clipsToBounds = false
        return imageView
    }()

    private let rotateButton: UIButton = {
        let button = UIButton()
        button.translatesAutoresizingMaskIntoConstraints = false
        let newSize = CGSize(width: 25, height: 25)
        let image = UIImage(systemName: "rotate.left")
        let resizedImage = image?.withConfiguration(UIImage.SymbolConfiguration(pointSize: newSize.width, weight: .medium))
        button.setImage(resizedImage, for: .normal)
        button.tintColor = .systemPink
        button.isHidden = true
        return button
    }()

    private let deleteButton: UIButton = {
        let button = UIButton()
        button.translatesAutoresizingMaskIntoConstraints = false
        let newSize = CGSize(width: 25, height: 25)
        let image = UIImage(systemName: "trash")
        let resizedImage = image?.withConfiguration(UIImage.SymbolConfiguration(pointSize: newSize.width, weight: .medium))
        button.setImage(resizedImage, for: .normal)
        button.tintColor = .systemPink
        button.isHidden = true
        return button
    }()

    private var topLeftCircleView = CircleView()
    private var topRightCircleView = CircleView()
    private var bottomLeftCircleView = CircleView()
    private var bottomRightCircleView = CircleView()

    private var borderView = UIView()

    private var imageViewTopConstraint: NSLayoutConstraint!
    private var imageViewBottomConstraint: NSLayoutConstraint!
    private var imageViewLeftConstraint: NSLayoutConstraint!
    private var imageViewRightConstraint: NSLayoutConstraint!

    private var rotateButtonBottomAnchorConstraint: NSLayoutConstraint!
    private var rotateButtonTrailingAnchorConstraint: NSLayoutConstraint!
    private var deleteButtonTopAnchorConstraint: NSLayoutConstraint!
    private var deleteButtonTrailingAnchorConstraint: NSLayoutConstraint!

 private var isResizing: Bool = false {
        didSet {
            [topLeftCircleView, topRightCircleView, bottomLeftCircleView, bottomRightCircleView, rotateButton, deleteButton].forEach { $0.isHidden = !isResizing }
            borderView.layer.borderWidth = isResizing ? 2.0 : 0.0
        }
    }

    private var originalImageFrame: CGRect = .zero
    private var resizeRect = ResizeRect()
    private var proxyFactor: CGFloat = 10.0

    private var rotationGesture: UIRotationGestureRecognizer!

override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = .white

        setupView()
        addConstraintsForItems()
        createCircles()

        addTapGestureRecognizer()
        addPinchGestureRecognizer()
        addRotationGesture()
        addDeletePhotoButton()
    }

这是设置代码，以备不时之需。 这是约束代码：

 private func addConstraintsForItems() {
        imageViewTopConstraint = imageView.topAnchor.constraint(equalTo: view.topAnchor, constant: 180)
        imageViewBottomConstraint = view.bottomAnchor.constraint(equalTo: imageView.bottomAnchor, constant: 180)
        imageViewLeftConstraint = imageView.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 60)
        imageViewRightConstraint = view.trailingAnchor.constraint(equalTo: imageView.trailingAnchor, constant: 70)

        NSLayoutConstraint.activate([imageViewTopConstraint, imageViewBottomConstraint, imageViewLeftConstraint, imageViewRightConstraint])

        let borderViewTopConstraint = borderView.topAnchor.constraint(equalTo: imageView.topAnchor)
        let borderViewLeftConstraint = borderView.leadingAnchor.constraint(equalTo: imageView.leadingAnchor)
        let borderViewRightConstraint = borderView.trailingAnchor.constraint(equalTo: imageView.trailingAnchor)
        let borderViewBottomConstraint = borderView.bottomAnchor.constraint(equalTo: imageView.bottomAnchor)

        NSLayoutConstraint.activate([borderViewTopConstraint, borderViewLeftConstraint, borderViewRightConstraint, borderViewBottomConstraint])

        rotateButtonBottomAnchorConstraint = rotateButton.centerYAnchor.constraint(equalTo: imageView.centerYAnchor, constant: -20)
        rotateButtonTrailingAnchorConstraint = rotateButton.trailingAnchor.constraint(equalTo: imageView.trailingAnchor, constant: 40)

        NSLayoutConstraint.activate([rotateButtonBottomAnchorConstraint, rotateButtonTrailingAnchorConstraint])

        deleteButtonTopAnchorConstraint = deleteButton.centerYAnchor.constraint(equalTo: imageView.centerYAnchor, constant: 20)
        deleteButtonTrailingAnchorConstraint = deleteButton.trailingAnchor.constraint(equalTo: imageView.trailingAnchor, constant: 40)

        NSLayoutConstraint.activate([deleteButtonTopAnchorConstraint, deleteButtonTrailingAnchorConstraint])
    }

下面是我如何放大我的图像并旋转它：

 @objc private func handlePincheGesture(_ gestureRecognizer: UIPinchGestureRecognizer) {
        if gestureRecognizer.state == .began {
            isResizing = false
        }
        gestureRecognizer.view?.transform = (gestureRecognizer.view?.transform)!.scaledBy(x: gestureRecognizer.scale, y: gestureRecognizer.scale)
        gestureRecognizer.scale = 1.0
        if gestureRecognizer.state == .ended {
            isResizing = true
        }
    }

@objc private func handleRotationGesture(_ gestureRecognizer: UIRotationGestureRecognizer) {
        if gestureRecognizer.state == .began {
            isResizing = false
        }
        if let view = gestureRecognizer.view {
            view.transform = view.transform.rotated(by: gestureRecognizer.rotation)
            gestureRecognizer.rotation = 0
        }
        if  gestureRecognizer.state == .ended {
            isResizing = true
        }
    }

position 的按键应该怎么处理才正常？

Answer 1

我想出了一个仍然需要改进的解决方案，但这是一个好的开始，基本上你需要将这些按钮添加到 stackView，将这个 stackView 添加到视图，像图像一样约束它。 之后，在旋转方法中，您可以添加一行以在转换视图时也转换 stackView。

@objc private func handleRotationGesture(_ gestureRecognizer: UIRotationGestureRecognizer) {
        if gestureRecognizer.state == .began {
            isResizing = false
        }
        if let view = gestureRecognizer.view {
            view.transform = view.transform.rotated(by: gestureRecognizer.rotation)
            stackView.transform = stackView.transform.rotated(by: gestureRecognizer.rotation) // this line
            gestureRecognizer.rotation = 0
        }
        if  gestureRecognizer.state == .ended {
            isResizing = true
        }
    }

此外，如果您需要捏合图像，您可以使用相同的逻辑并将缩放比例除以 2，这样按钮就不会变得很大。 但同样，这仍然需要改进。