iOS 10 自定义导航栏高度

Question

我实现了自定义导航栏高度，通过使用以下代码对其进行子类化

class TMNavigationBar: UINavigationBar {

    ///The height you want your navigation bar to be of
    static let navigationBarHeight: CGFloat = 44.0

    ///The difference between new height and default height
    static let heightIncrease:CGFloat = navigationBarHeight - 44

    override init(frame: CGRect) {
        super.init(frame: frame)
        initialize()
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        initialize()
    }

    private func initialize() {
        let shift = TMNavigationBar.heightIncrease/2

        ///Transform all view to shift upward for [shift] point
        self.transform =
            CGAffineTransformMakeTranslation(0, -shift)
    }

    override func layoutSubviews() {
        super.layoutSubviews()

        let shift = TMNavigationBar.heightIncrease/2

        ///Move the background down for [shift] point
        let classNamesToReposition: [String] = ["_UINavigationBarBackground"]
        for view: UIView in self.subviews {
            if classNamesToReposition.contains(NSStringFromClass(view.dynamicType)) {
                let bounds: CGRect = self.bounds
                var frame: CGRect = view.frame
                frame.origin.y = bounds.origin.y + shift - 20.0
                frame.size.height = bounds.size.height + 20.0
                view.frame = frame
            }
        }
    }

    override func sizeThatFits(size: CGSize) -> CGSize {
        let amendedSize:CGSize = super.sizeThatFits(size)
        let newSize:CGSize = CGSizeMake(amendedSize.width, TMNavigationBar.navigationBarHeight);
        return newSize;
    }
}

以下问题仅在 iOS 10 上出现：（栏和视图之间的黑色空间）

不知道那里发生了什么。但是在情节提要中它会生成此警告，并且无法在 IB 中修复它（警告仅在我更改 IB 中导航栏的子类时出现）。

Answer 1

适用于 iOS 10、Swift 3.0：

extension UINavigationBar {
    open override func sizeThatFits(_ size: CGSize) -> CGSize {
        let screenRect = UIScreen.main.bounds
        return CGSize(width: screenRect.size.width, height: 64)
    }
}

Answer 2

我检查了界面调试器，这就是我所看到的（所以基本上它是在尝试改变导航栏的高度，它保持不变并且只显示黑色空间 - 这是窗口颜色）：

经过后来的调查，我注意到它没有调用：“_UINavigationBarBackground”

然后我从快速枚举中检查了view.classForCoder，发现key变成了“_UIBarBackground”，所以我更新了layoutSubviews()：

override func layoutSubviews() {
    super.layoutSubviews()

    let shift = TMNavigationBar.heightIncrease/2

    ///Move the background down for [shift] point
    let classNamesToReposition = isIOS10 ? ["_UIBarBackground"] : ["_UINavigationBarBackground"]

    for view: UIView in self.subviews {

        if classNamesToReposition.contains(NSStringFromClass(view.classForCoder)) {
            let bounds: CGRect = self.bounds
            var frame: CGRect = view.frame
            frame.origin.y = bounds.origin.y + shift - 20.0
            frame.size.height = bounds.size.height + 20.0
            view.frame = frame
        }
    }
}

干杯。