导航栏 - 重新启动应用

Question

我为导航栏设置了自定义高度，状态栏也隐藏了：

override func viewDidLayoutSubviews() {
    let bounds = self.navigationController!.navigationBar.bounds
    self.navigationController?.navigationBar.frame = CGRect(x: 0, y: 0, width: bounds.width, height: 60)
}
override var prefersStatusBarHidden: Bool {
    return true
}

我也尝试过：

override func viewDidAppear(_ animated: Bool) {
    self.navigationController!.navigationBar.frame = CGRect(x: 0, y: 0, width: self.view.frame.size.width, height: 40)

}

但重新启动应用后，顶部有一种填充：

我看到了answer：

override func viewWillAppear(_ animated: Bool) {
    let bounds = self.navigationController!.navigationBar.bounds
    navigationController?.isNavigationBarHidden = true
    let navBar: UINavigationBar = UINavigationBar(frame: CGRect(x: 0, y: 0, width: bounds.width, height: 60))
    self.view.addSubview(navBar);
    let navItem = UINavigationItem(title: "Add");
    let doneItem = UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.done, target: nil, action: #selector(addNewRecipe(_:)));
    navItem.rightBarButtonItem = doneItem;
    navBar.setItems([navItem], animated: false);
    view.addSubview(navBar)
}

除了隐藏导航栏并以编程方式编写每个导航项外，还有其他方法吗？

谢谢！

Answer 1

详细

xCode 8.3，Swift 3.1

完整样本

  

类

.aspx

  

Main.storyboard

UID00000004

结果