使NavigationBar的titleView大于其自身

覆盖功能funD viewDidAppear(_动画:布尔){用于视图:(navigationController?.navigationBar.subviews)中的UIView！{view.clipsToBounds = false;}navigationItem.titleView?.layoutIfNeeded()}覆盖func viewWillAppear(_动画:布尔){用于视图:(navigationController?.navigationBar.subviews)中的UIView！{view.clipsToBounds = false;}navigationItem.titleView?.layoutIfNeeded()} 我尝试了，而且行得通.但是我认为您不应该这样做，因为这是私人观点.也许苹果不希望我们对此做任何事情.希望我的建议可以为您提供帮助.祝你好运;) 解决方案 为 _UINavigationBarContentView.clipsToBounds 添加观察者，每次更改为 false 时，将其设置为 true ，并更新 titleView的布局 覆盖功能funD viewDidLoad(){super.viewDidLoad()//加载视图后进行其他任何设置，通常是从笔尖进行.让徽标= UIImage(名称:徽标")让titleView = UIView(frame:CGRect(x:0，y:0，width:60，height:60))让imageView = UIImageView(图像:徽标)imageView.frame = CGRect(x:0，y:0，宽度:titleView.frame.width，高度:titleView.frame.height)titleView.addSubview(imageView)imageView.contentMode = .scaleAspectFitimageView.image =徽标navigationItem.titleView = titleViewnavigationController?.navigationBar.subviews [2] .addObserver(自己，forKeyPath:"clipsToBounds"，选项:[.old，.new]，上下文:nil)}覆盖函数funcValueValue(forKeyPath keyPath:String ?，对象:Any ?，更改:[NSKeyValueChangeKey:Any] ?，上下文:UnsafeMutableRawPointer?){如果(navigationController?.navigationBar.subviews [2] .isEqual(object))！{DispatchQueue.main.async {self.navigationController?.navigationBar.subviews [2] .clipsToBounds = falseself.navigationItem.titleView?.layoutIfNeeded()}}}取消初始化{navigationController?.navigationBar.subviews [2] .removeObserver(自己，forKeyPath:"clipsToBounds")} 更详细，更轻松的操作，可以在这里查看我的演示 https://github.com/trungducc/stackoverflow/tree/big-title-navigation-bar I want to place an image in the middle of a navigation bar that is bigger then the bar itself. So far I tried to use a UIView with a UIImageView inside and it works quite well as you can see here:However as soon as I push another controller and pop back my ImageView gets cropped to the size of the NavigationBar again.Any ideas on how to prevent the cropping?My code so far for iOS 11:override func viewDidLoad() { super.viewDidLoad() let logo = UIImage(named: "Logo") let titleView = UIView(frame: CGRect(x: 0, y: 0, width: 60, height: 60)) let imageView = UIImageView(image: logo) imageView.frame = CGRect(x: 0, y: 0, width: titleView.frame.width, height: titleView.frame.height) titleView.addSubview(imageView) imageView.contentMode = .scaleAspectFit imageView.image = logo navigationItem.titleView = titleView}Edit: Currently there is a temporary solution which uses an observer to overwrite the clipsToBounds property of the view that causes the trouble: Link (shout out to @trungduc for that) 解决方案 I found why you got this issue. It's because of a private view which has name _UINavigationBarContentView. It's a subview of UINavigationBar. navigationItem.titleView is contained in this view.At first time, when you change navigationItem.titleView. _UINavigationBarContentView.clipsToBounds is false .But after you push another controller and pop back, _UINavigationBarContentView.clipsToBounds is true. That's why titleView is cropped.So i have a temporary solution. Each time when viewController appears, find this view and change _UINavigationBarContentView.clipsToBounds to false and layout titleView.override func viewDidAppear(_ animated: Bool) { for view : UIView in (navigationController?.navigationBar.subviews)! { view.clipsToBounds = false; } navigationItem.titleView?.layoutIfNeeded() } override func viewWillAppear(_ animated: Bool) { for view : UIView in (navigationController?.navigationBar.subviews)! { view.clipsToBounds = false; } navigationItem.titleView?.layoutIfNeeded() }I tried and it works. But i think you shouldn't do something whit it because it's private view. Maybe Apple don't want us do anything with it.Hope somehow my suggestion can help you. Good luck ;)SOLUTIONAdding observer for _UINavigationBarContentView.clipsToBounds, each time when it changes to false, set to true and update layout of titleViewoverride func viewDidLoad() { super.viewDidLoad() // Do any additional setup after loading the view, typically from a nib. let logo = UIImage(named: "Logo") let titleView = UIView(frame: CGRect(x: 0, y: 0, width: 60, height: 60)) let imageView = UIImageView(image: logo) imageView.frame = CGRect(x: 0, y: 0, width: titleView.frame.width, height: titleView.frame.height) titleView.addSubview(imageView) imageView.contentMode = .scaleAspectFit imageView.image = logo navigationItem.titleView = titleView navigationController?.navigationBar.subviews[2].addObserver(self, forKeyPath: "clipsToBounds", options: [.old, .new], context: nil)}override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) { if (navigationController?.navigationBar.subviews[2].isEqual(object))! { DispatchQueue.main.async { self.navigationController?.navigationBar.subviews[2].clipsToBounds = false self.navigationItem.titleView?.layoutIfNeeded() } }}deinit { navigationController?.navigationBar.subviews[2].removeObserver(self, forKeyPath: "clipsToBounds")}For more detail and easier, you can check my demo here https://github.com/trungducc/stackoverflow/tree/big-title-navigation-bar 这篇关于使NavigationBar的titleView大于其自身的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！