设备旋转时调整插入 UITextView 的大小

Question

我有一个名为 detailView 的 UIView，它有两个子视图，一个名为 detailTextView 的 UITextView 和一个名为 detailImageView 的 UIImageView，它们是彼此的兄弟。 detailView 包含在拆分视图的默认详细信息 UIView 中。我正在使用自动调整大小在我的主情节提要中设置所有这些。从视觉上看，层次结构如下：

Top Layout Guide
Bottom Layout Guide
View
- Detail View
- - Detail Text View
- - Detail Image View
Navigation Item

detailTextView 从每边插入 10%，边缘模糊，当视图出现时在图像顶部交叉溶解，如下：

/**
 - reference:
 Joy, V. (2016, December 15). Swift 3: How to create blurred side edges/
 corners of a UIImageView?. Message posted to
 https://stackoverflow.com/a/41158594/6084947
 */
internal override func viewDidAppear(_ animated: Bool) {
    print("detailViewDidAppear")

    super.viewDidAppear(animated)

    // Resize the text view.
    let inset = detailView.bounds.width * 0.2
    detailTextView.frame = CGRect(
        x: inset / 2,
        y: inset / 2,
        width: detailView.bounds.width - inset,
        height: detailView.bounds.height - inset
    )

    // Set up text view attributes.
    detailTextView.allowsEditingTextAttributes = true

    let xInset = detailTextView.bounds.width * 0.05
    let yInset = detailTextView.bounds.height * 0.05
    detailTextView.textContainerInset = UIEdgeInsetsMake(
        yInset,
        xInset,
        yInset,
        xInset
    )

    // Blur edges of text view (see Joy, 2016).
    let maskLayer = CAGradientLayer()
    maskLayer.frame = detailTextView.bounds
    maskLayer.shadowRadius = 5
    maskLayer.shadowPath = CGPath(
        roundedRect: detailTextView.bounds.insetBy(dx: 5, dy: 5),
        cornerWidth: 10,
        cornerHeight: 10,
        transform: nil
    )
    maskLayer.shadowOpacity = 1
    maskLayer.shadowOffset = CGSize.zero
    maskLayer.shadowColor = UIColor.white.cgColor
    detailTextView.layer.mask = maskLayer

    // Fade in text view.
    UIView.transition(
        with: detailView,
        duration: 3,
        options: .transitionCrossDissolve,
        animations:
        { self.detailView.bringSubview(toFront: self.detailTextView) },
        completion: nil
    )
}

问题是屏幕旋转时插入的 detailTextView 无法正确调整大小。从横向模式加载详细视图时，在 iPad 模拟器上旋转到纵向模式时，它不会填满超级视图。

我尝试了以下方法：

internal override func viewWillTransition(
    to size: CGSize,
    with coordinator: UIViewControllerTransitionCoordinator)
{
    print("viewWillTransition")

    super.viewWillTransition(to: size, with: coordinator)

    coordinator.animate(alongsideTransition: nil) {
        [unowned self] _ in

        // Resize text view.
        let inset = size.width * 0.2
        self.detailTextView.frame = CGRect(
            x: inset / 2,
            y: inset / 2,
            width: size.width - inset,
            height: size.height - inset
        )
    }
}

不幸的是，这无助于横向到纵向的过渡，并且给我留下了很多需要调整的界限。有什么建议吗？

Answer 1

问题不在于我的 UITextView 或其插图的大小调整，我发现它通过一些打印语句按预期自动工作。相反，问题在于我为模糊边缘创建的蒙版层没有调整大小。以下（使用 insetBy(dx:dy:) 更改 UITextView 的边界而不是其框架）是我更正的代码：

/**
 - reference:
 Joy, V. (2016, December 15). Swift 3: How to create blurred side edges/
 corners of a UIImageView?. Message posted to
 https://stackoverflow.com/a/41158594/6084947
 */
internal override func viewDidAppear(_ animated: Bool) {
    print("detailViewDidAppear")

    super.viewDidAppear(animated)

    // Resize the text view.
    let textViewInset = detailView.bounds.width * 0.1
    detailTextView.bounds = detailView.bounds.insetBy(
        dx: textViewInset,
        dy: textViewInset
    )

    // Set up text view attributes.
    detailTextView.allowsEditingTextAttributes = true

    let textContainerInset = detailTextView.bounds.width * 0.05
    detailTextView.textContainerInset = UIEdgeInsetsMake(
        textContainerInset,
        textContainerInset,
        textContainerInset,
        textContainerInset
    )

    // Blur edges of text view (see Joy, 2016).
    let maskLayer = CAGradientLayer()
    maskLayer.frame = detailTextView.bounds
    maskLayer.shadowRadius = 5
    maskLayer.shadowPath = CGPath(
        roundedRect: detailTextView.bounds.insetBy(dx: 5, dy: 5),
        cornerWidth: 10,
        cornerHeight: 10,
        transform: nil
    )
    maskLayer.shadowOpacity = 1
    maskLayer.shadowOffset = CGSize.zero
    maskLayer.shadowColor = UIColor.white.cgColor
    detailTextView.layer.mask = maskLayer

    // Fade in text view.
    UIView.transition(
        with: detailView,
        duration: 3,
        options: .transitionCrossDissolve,
        animations:
        { self.detailView.bringSubview(toFront: self.detailTextView) },
        completion: nil
    )
}

/**
 - reference:
 Joy, V. (2016, December 15). Swift 3: How to create blurred side edges/
 corners of a UIImageView?. Message posted to
 https://stackoverflow.com/a/41158594/6084947
 */
internal override func viewWillTransition(
    to size: CGSize,
    with coordinator: UIViewControllerTransitionCoordinator)
{
    print("viewWillTransition")

    super.viewWillTransition(to: size, with: coordinator)

    coordinator.animate(alongsideTransition: nil) {
        [unowned self] _ in

        // Blur edges of text view (see Joy, 2016).
        let maskLayer = CAGradientLayer()
        maskLayer.frame = self.detailTextView.bounds
        maskLayer.shadowRadius = 5
        maskLayer.shadowPath = CGPath(
            roundedRect: self.detailTextView.bounds.insetBy(dx: 5, dy: 5),
            cornerWidth: 10,
            cornerHeight: 10,
            transform: nil
        )
        maskLayer.shadowOpacity = 1
        maskLayer.shadowOffset = CGSize.zero
        maskLayer.shadowColor = UIColor.white.cgColor
        self.detailTextView.layer.mask = maskLayer
    }
}