iOS swift5 自定义导航栏

    lazy var navItem:UINavigationItem = {
        let navItem = UINavigationItem()
        navItem.leftBarButtonItem = UIBarButtonItem(image: UIImage(named: "icon_back"), style: .plain, target: self, action: #selector(leftBarBtnItemClick))
        navItem.rightBarButtonItem = UIBarButtonItem(title: "发布", style: .plain, target: self, action: #selector(rightBarBtnItemClick))
        navItem.title = "发布动态"
        return navItem
    }()
    
    lazy var customNavBar:UINavigationBar = {
        let customNavBar = UINavigationBar(frame: CGRect(x: 0, y: XYHelper.statusBarHeight, width: windowWidth, height: navigationBarHeight))
        customNavBar.tintColor = .black
        //设置背为透明，不会有遮挡
        customNavBar.setBackgroundImage(UIImage(), for: .default)
        //去掉下面的线
        customNavBar.shadowImage = UIImage()
        customNavBar.pushItem(navItem, animated: false)
        
       return customNavBar
    }()

    override func viewDidLoad() {
        super.viewDidLoad()
        navigationController?.navigationBar.isHidden = true
        
        setupUI()
        
        view.addSubview(customNavBar)
    }

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ios swift5 获取状态栏(电池栏)和导航栏高度