我的应用程序中有一个导航栏，正在尝试添加一个与页面右侧齐平的右键。但是，每当我尝试将其锚定在右侧时，它仍然是侧面的16px边距。
我的代码如下：
func setupNavigationBarItems(){
//title label
let titleLabel = UILabel(frame: CGRect(x: 0, y: 0, width: view.frame.width - 32, height: view.frame.height))
//Set logo Colors
myMutableString = NSMutableAttributedString(string: myString as String, attributes: [NSAttributedStringKey.font:UIFont(name: Helpers.Fonts.Medium, size: 24.0)!])
myMutableString.addAttribute(NSAttributedStringKey.foregroundColor, value: Helpers.Colors.White, range: NSRange(location:0,length:12))
myMutableString.addAttribute(NSAttributedStringKey.foregroundColor, value: Helpers.Colors.Red, range: NSRange(location:12,length:1))
titleLabel.attributedText = myMutableString
//freeBusy button
let freeBusyButton = UIButton(type: .system)
freeBusyButton.setImage(#imageLiteral(resourceName: "free").withRenderingMode(.alwaysOriginal), for: .normal)
freeBusyButton.frame = CGRect(x: 0, y: 0, width: view.frame.width + 32, height: view.frame.height)
freeBusyButton.widthAnchor.constraint(equalToConstant: 40).isActive = true
freeBusyButton.heightAnchor.constraint(equalToConstant: view.frame.height).isActive = true
freeBusyButton.rightAnchor.constraint(equalTo: view.rightAnchor).isActive = true
navigationItem.titleView = titleLabel
navigationController?.navigationBar.isTranslucent = false
navigationItem.rightBarButtonItems = [UIBarButtonItem(customView:freeBusyButton)]
}