Question

我尝试创建一个NavBar，到目前为止NavBar没有问题，但如果我尝试添加按钮和标题，我会被吸。

我的NavBar看起来像

let NameHeight = screenHeight * 0.09
let NameWidth = screenWidth
let navBar: UINavigationBar = UINavigationBar(frame: CGRect(x: 0, y: 0, width: NameWidth, height: NameHeight))
self.view.addSubview(navBar)

所以我尝试将我的NavBar标题设置为

navigationBar.topItem.title = "some title"
or
navigationBar.title = "some title"

但都失败了此外，如果我尝试设置按钮

let btnName = UIButton()
btnName.setImage(UIImage(named: "imagename"), forState: .Normal)
btnName.frame = CGRectMake(0, 0, 30, 30)
btnName.addTarget(self, action: Selector("action"), forControlEvents: .TouchUpInside)

//.... Set Right/Left Bar Button item
let rightBarButton = UIBarButtonItem()
rightBarButton.customView = btnName
self.navigationItem.rightBarButtonItem = rightBarButton

这不会给我一个错误，但按钮根本不显示

Answer 1

更新了Swift 4

您必须创建导航项目实例并为其设置标题和向右/向左按钮。配置导航项后，将其添加到导航栏。

let navBar = UINavigationBar(frame: CGRect(x: 0, y: 0, width: 320, height: 44))
view.addSubview(navBar)

let navItem = UINavigationItem(title: "SomeTitle")
let doneItem = UIBarButtonItem(barButtonSystemItem: UIBarButtonItem.SystemItem.done, target: nil, action: #selector(selectorName:))
navItem.rightBarButtonItem = doneItem

navBar.setItems([navItem], animated: false)

Answer 2

基本上azimov在 Swift 4

中的回答

override func viewDidLoad() {
    super.viewDidLoad()
    self.setNavigationBar()
}

func setNavigationBar() {
    let screenSize: CGRect = UIScreen.main.bounds
    let navBar = UINavigationBar(frame: CGRect(x: 0, y: 0, width: screenSize.width, height: 44))
    let navItem = UINavigationItem(title: "")
    let doneItem = UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.done, target: nil, action: #selector(done))
    navItem.rightBarButtonItem = doneItem
    navBar.setItems([navItem], animated: false)
    self.view.addSubview(navBar)
}

@objc func done() { // remove @objc for Swift 3

}

使用Button和Title Swift以编程方式创建NavBar

2 个答案: