使用大导航标题滚动 table 时如何管理导航栏的两个按钮?

How can i manage both button of navigation bar when scrolling table with large navigation title?

在这里我可以附上我在滚动时遇到的问题的屏幕截图,我想隐藏更多按钮或将该按钮作为第二个按钮放入导航栏,但它被覆盖到第一个。

我通过调用这个函数将按钮设置为加载。

func setUpNavigationMoreButton() {
    let rightButton = UIButton()
    let btnFilterImage = #imageLiteral(resourceName: "DotsThreeOutline")
    rightButton.setImage(btnFilterImage, for: .normal)
    rightButton.setTitleColor(.purple, for: .normal)
    rightButton.addTarget(self, action: #selector(filterClick), for: .touchUpInside)
    navigationController?.navigationBar.addSubview(rightButton)
    rightButton.tag = 1
    rightButton.frame = CGRect(x: self.view.frame.width, y: 0, width: 30, height: 30)
    
    let targetView = self.navigationController?.navigationBar
    
    let trailingContraint = NSLayoutConstraint(item: rightButton, attribute:
            .trailingMargin, relatedBy: .equal, toItem: targetView,
                                               attribute: .trailingMargin, multiplier: 1.0, constant: -16)
    let bottomConstraint = NSLayoutConstraint(item: rightButton, attribute: .bottom, relatedBy: .equal,
                                              toItem: targetView, attribute: .bottom, multiplier: 1.0, constant: -6)
    rightButton.translatesAutoresizingMaskIntoConstraints = false
    NSLayoutConstraint.activate([trailingContraint, bottomConstraint])
}

您必须使用 UIBarButtonItem 而不是 UIButton。

let btnFilterImage = #imageLiteral(resourceName: "DotsThreeOutline")
let rightButton = UIBarButtonItem(image: btnFilterImage, style: .plain, target: self, action: #selector(filterClick))
    
navigationController?.navigationItem.rightBarButtonItem = rightButton

如果您有多个按钮

let rightButton1 = UIBarButtonItem(image: image1, style: .plain, target: self, action: #selector(filterClick))

let rightButton2 = UIBarButtonItem(image: image2, style: .plain, target: self, action: #selector(filterClick))

navigationController?.navigationItem.rightBarButtonItems = [rightButton1, rightButton2]

如果您需要hide/unhide大标题更改时的更多按钮。

class VController: UIViewController {

    let rightButton = UIButton()
    var observer: NSKeyValueObservation?

    override func viewDidLoad() {
        super.viewDidLoad()
        self.observer = self.navigationController?.navigationBar.observe(\.bounds, options: [.new], changeHandler: { (navigationBar, changes) in
            if let height = changes.newValue?.height {
                if height > 44.0 {
                    //Large Title, unhide button
                    rightButton.isHidden = false
                } else {
                    //Small Title, hide button
                    rightButton.isHidden = true
                }
            }
        })
    }
}