UIBarButtonItem大小显示错误

Question

我有一些自定义UINavigationBar（用于JSQMessagesViewController）。但是我对leftBarButtonItem

有一些疑问

func setNavigationBar() {
    let screenSize: CGRect = UIScreen.main.bounds
    let navBar = UINavigationBar(frame: CGRect(x: 0, y: 28, width: screenSize.width, height: 78))
    let navItem = UINavigationItem(title: chatName ?? "chat")
    let menuBtn = UIButton(type: .custom)
    menuBtn.frame = CGRect(x: 0.0, y: 0.0, width: 78, height: 78)
    menuBtn.setImage(UIImage(named: "backButton"), for: .normal)
    menuBtn.addTarget(self, action: #selector(back), for: UIControl.Event.touchUpInside)

    let menuBarItem = UIBarButtonItem(customView: menuBtn)
    let currWidth = menuBarItem.customView?.widthAnchor.constraint(equalToConstant: 78)
    currWidth?.isActive = true
    let currHeight = menuBarItem.customView?.heightAnchor.constraint(equalToConstant: 78)
    currHeight?.isActive = true
    navItem.leftBarButtonItem = menuBarItem


    navBar.titleTextAttributes = [.font : UIFont(name: "Acrom-Bold", size: 26)!, .foregroundColor : UIColor.white]
    navBar.setItems([navItem], animated: false)
    navBar.setBackgroundImage(UIImage(), for: .default)
    navBar.shadowImage = UIImage()
    navBar.backgroundColor = UIColor(displayP3Red: 0, green: 0, blue: 0, alpha: 0.3)
    navBar.isTranslucent = true

    self.view.addSubview(navBar)
}

但是我的BackButton看起来不对。 按钮的高度有什么问题？

Answer 1

如果条形按钮项具有自定义视图，则必须使用内部自动布局约束来调整自定义视图的宽度。

但是，您不能像执行操作那样将高度设置为大于运行时所喜欢的高度。删除这些行：

let currHeight = menuBarItem.customView?.heightAnchor.constraint(equalToConstant: 78)
currHeight?.isActive = true