ios – 如何才能在一个视图控制器中使UINavigationController透明？

我想只在一个ViewController中使NavigationBar透明.但是,在单个ViewController中更改NavigationBar后,整个navigationController变得透明,并在几秒钟后崩溃.这是我的代码块：

override func viewWillAppear(animated: Bool) {
        self.navigationController!.navigationBar.setBackgroundImage(UIImage(),forBarMetrics: UIBarMetrics.Default)
        self.navigationController?.navigationBar.shadowImage = UIImage()
        self.navigationController?.navigationBar.translucent = true
        self.navigationController!.view.backgroundColor = UIColor.clearColor()
    }



override func viewDidDisappear(animated: Bool) {
        self.navigationController!.navigationBar.setBackgroundImage(nil,forBarMetrics: UIBarMetrics.Default)
        self.navigationController?.navigationBar.shadowImage = nil
        self.navigationController?.navigationBar.translucent = true

    }

它崩溃了

self.navigationController!.navigationBar.setBackgroundImage(nil,forBarMetrics: UIBarMetrics.Default)

解决方法

尝试给出代码,使导航栏在swift中透明： –

self.navigationController!.navigationBar.setBackgroundImage(UIImage(),forBarMetrics: UIBarMetrics.Default)
    self.navigationController?.navigationBar.shadowImage = UIImage()
    self.navigationController?.navigationBar.translucent = true
    self.navigationController!.view.backgroundColor = UIColor.clearColor()
    self.navigationController?.navigationBar.backgroundColor = UIColor.clearColor()

希望这段代码能帮到你..谢谢