ios - 我如何为 Peek 和 Pop 3D Touch 圆化 sourceRect 的角？

Question

在 Safari 中，如果您使用 3D 触摸，则被触摸的链接的 sourceRect 具有圆角。当我在以下位置设置源矩形时:func previewingContext(previewingContext: UIViewControllerPreviewing, viewControllerForLocation location: CGPoint) -> UIViewController? {在 previewingContext 上，我只能设置 previewingContext.sourceRect，这不允许我圆角或设置多角区域。我该怎么做？

Answer 1

您可以通过向 sourceView 的层添加圆角半径来间接为 sourceRect 设置圆角。当您将 previewingContext.sourceRect 设置为 sourceView 的边界时，保持焦点的区域也将具有圆角。

这是一个使用可按下的 UILabel 的示例:

class ViewController: UIViewController {

    var previewingContext: UIViewControllerPreviewing?
    let label = UILabel(frame: CGRectMake(150, 250, 100, 50))

    override func viewDidLoad() {
        super.viewDidLoad()

        let background = UIImageView(frame: view.bounds)
        background.image = UIImage(named: "image.jpg")
        view.addSubview(background)

        label.backgroundColor = UIColor.whiteColor()
        label.text = "Press me!"
        label.textAlignment = .Center
        label.layer.cornerRadius = 20
        label.clipsToBounds = true
        label.userInteractionEnabled = true
        view.addSubview(label)

        previewingContext = registerForPreviewingWithDelegate(self, sourceView: label)
    }
}

extension ViewController: UIViewControllerPreviewingDelegate {

    func previewingContext(previewingContext: UIViewControllerPreviewing, viewControllerForLocation location: CGPoint) -> UIViewController? {
        previewingContext.sourceRect = label.bounds

        return UIViewController()
    }

    func previewingContext(previewingContext: UIViewControllerPreviewing, commitViewController viewControllerToCommit: UIViewController) {
        showViewController(viewControllerToCommit, sender: self)
    }
}