iOS导航栏一些问题

禁止iOS14返回按钮菜单

iOS14之后，长按返回按钮会弹出可返回的控制器。iOS14，UIBarButtonItem 新增了一个menu类型，可新建子类，重写menu的set方法

class BackBarButtonItem: UIBarButtonItem {
    @available(iOS 14.0, *)
    override var menu: UIMenu? {
        set {
            // Don't set the menu here
            // super.menu = menu
        }
        get {
            return super.menu
        }
    }
}

使用BackBarButtonItem创建backBarButtonItem ：

1 2	let backItem = BackBarButtonItem(title: "", style: .plain, target: nil, action: nil) self.navigationItem.backBarButtonItem = backItem

参考链接：ios - 是否可以在iOS 14+中禁用后退导航菜单？

拦截系统导航栏返回操作

swift通过分类实现：

/// 导航返回协议
@objc protocol NavigationProtocol {
    /// 导航将要返回方法
    /// - Returns: true: 返回上一界面， false: 禁止返回
    @objc optional func navigationShouldPopMethod() -> Bool
}
extension UIViewController: NavigationProtocol {
    func navigationShouldPopMethod() -> Bool {
        return true
    }
}
extension UINavigationController: UINavigationBarDelegate, UIGestureRecognizerDelegate {
    public func navigationBar(_ navigationBar: UINavigationBar, shouldPop item: UINavigationItem) -> Bool {
        if viewControllers.count < (navigationBar.items?.count)! {
            return true
        }
        var shouldPop = false
        let vc: UIViewController = topViewController!
        if vc.responds(to: #selector(navigationShouldPopMethod)) {
            shouldPop = vc.navigationShouldPopMethod()
        }
        if shouldPop {
            DispatchQueue.main.async {
                self.popViewController(animated: true)
            }
        } else {
            for subview in navigationBar.subviews {
                if 0.0 < subview.alpha && subview.alpha < 1.0 {
                    UIView.animate(withDuration: 0.25) {
                        subview.alpha = 1.0
                    }
                }
            }
        }
        return false
    }
		public func gestureRecognizerShouldBegin(_ gestureRecognizer: UIGestureRecognizer) -> Bool {
        if children.count == 1 {
            return false
        } else {
            if topViewController?.responds(to: #selector(navigationShouldPopMethod)) != nil {
                return topViewController!.navigationShouldPopMethod()
            }
            return true
        }
    }
}

在需要拦截返回的控制器中重写该方法：

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override func navigationShouldPopMethod() -> Bool {
	return false //拦截返回
}

参考链接：iOS 拦截系统导航栏返回按钮事件

UIBarButtonItem按钮图片颜色

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let image = UIImage(named: "imagename")?.withRenderingMode(.alwaysOriginal) //设置图片mode
self.navigationItem.rightBarButtonItem = UIBarButtonItem(image: image, style: .plain, target: self, action: #selector(itemClick(item:)))

导航栏透明

1 2	self.navigationBar.setBackgroundImage(UIImage(), for: .default) self.navigationBar.shadowImage = UIImage()

自定义导航栏按钮

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let rightBtn = CustomButton(frame: CGRect(x: 0, y: 0, width: 30, height: 40))
rightBtn.addTarget(self, action: #selector(itemDeleteBtnClick), for: .touchUpInside)
self.navigationItem.rightBarButtonItem = UIBarButtonItem(customView: rightBtn)