iMessage(iOS 10)中的导航栏高度

您可以使用动画更改导航栏的高度,方法是对其进行子类化,创建高度属性(barHeight),并在设置值后设置其动画。

final class CustomHeightNavigationBar: UINavigationBar {

var navigationItemsOffset: CGPoint = CGPoint(x: 0, y: 10) { // default offset (below statusbar)
    didSet {
        UIView.animate(withDuration: 0.25) { [weak self] in
            self?.setNeedsLayout()
        }
    }
}

var barHeight: CGFloat = 60 { // default height
    didSet {
        UIView.animate(withDuration: 0.25) { [weak self] in
            self?.sizeToFit()
            self?.setNeedsLayout()
        }
    }
}

override func sizeThatFits(_ size: CGSize) -> CGSize {
    return CGSize(width: UIScreen.main.bounds.size.width, height: barHeight)
}

override func layoutSubviews() {
    super.layoutSubviews()

    frame.origin = navigationItemsOffset

    subviews.forEach { (subview) in
        subview.center.y = center.y
    }
}

创建子类后,必须将其设置为序列图像板中导航栏的自定义类,该序列图像板位于导航控制器中。

现在,您可以通过更改barHeight属性的值来设置视图控制器中导航栏高度的动画。

Swift 3

var navigationBar: CustomHeightNavigationBar? {
    guard let navigationBar = navigationController?.navigationBar as? CustomHeightNavigationBar else {
        return nil
    }
    return navigationBar
}

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    if let navigationBar = navigationBar {
        navigationBar.barHeight = 60
    }
}

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)
    if let navigationBar = navigationBar {
        navigationBar.barHeight = 44
    }
}

为了在与过渡完全相同的时间为条的高度设置动画,必须在上实现此方法 viewWillAppear viewWillDisappear

        self.transitionCoordinator?.animate(alongsideTransition: { (context) in
        let height: CGFloat = 80 //any size you want
        let bounds = self.navigationController!.navigationBar.bounds
        self.navigationController?.navigationBar.frame = CGRect(x: 0, y: 0, width: bounds.width, height: height)

    }, completion: { (context) in
        //Any code you may want to add after the transition
    })