如何以编程方式在 Swift 中创建 "Back" UIBarButton 项目？

Question

我能够创建一个可以使用以下代码以编程方式返回的 UIBarButton 项目：

    func backAction() -> Void {        
        self.navigationController?.popViewControllerAnimated(true)
    }
override func viewDidLoad() {
        super.viewDidLoad()
    let backButton = UIBarButtonItem(title: "Back", style: UIBarButtonItemStyle.Plain, target: self, action: "backAction")

        self.navigationItem.leftBarButtonItem = backButton
    }

问题是后退按钮没有左箭头：有没有办法让它看起来像一个带有箭头的常规后退按钮，如下所示：

我也想知道是否有办法将按钮标题名称作为上一个视图控制器的标题，如果可能的话。

谢谢

Answer 1

您可以通过将视图嵌入导航控制器来实现。这是一张展示如何做到这一点的图片：

希望对你有帮助:D

Answer 2

下面是使用带有图像的 UIButton 的代码，您可以将其添加为 UIBarButtonItem 的自定义视图

override func viewDidLoad() {
    super.viewDidLoad()
    var backbutton = UIButton(type: .Custom)
    backbutton.setImage(UIImage(named: "BackButton.png"), forState: .Normal) // Image can be downloaded from here below link 
    backbutton.setTitle("Back", forState: .Normal)
    backbutton.setTitleColor(backbutton.tintColor, forState: .Normal) // You can change the TitleColor
    backbutton.addTarget(self, action: "backAction", forControlEvents: .TouchUpInside)

    self.navigationItem.leftBarButtonItem = UIBarButtonItem(customView: backbutton)
}

func backAction() -> Void {        
   self.navigationController?.popViewControllerAnimated(true)
}

Download Link

要使用之前的视图控制器标题设置后退按钮的标题，您必须在呈现控制器时将标题作为字符串传递，将上面的代码更改为

var titleStrFromPreviousController: String // This value has to be set from previous controller while presenting modal controller
backbutton.setTitle(titleStrFromPreviousController, forState: .Normal)

这可能会有所帮助。

Swift 3

override func viewDidLoad() {
    super.viewDidLoad()

    addBackButton()
}

func addBackButton() {
    let backButton = UIButton(type: .custom)
    backButton.setImage(UIImage(named: "BackButton.png"), for: .normal) // Image can be downloaded from here below link
    backButton.setTitle("Back", for: .normal)
    backButton.setTitleColor(backButton.tintColor, for: .normal) // You can change the TitleColor
    backButton.addTarget(self, action: #selector(self.backAction(_:)), for: .touchUpInside)

    self.navigationItem.leftBarButtonItem = UIBarButtonItem(customView: backButton)
}

@IBAction func backAction(_ sender: UIButton) {
   let _ = self.navigationController?.popViewController(animated: true)
}

Answer 3

第一个答案很好，但是图像有点太大所以使用预览并将其缩小到 width:13 和高度：22，同时将其渲染模式设置为 .alwaysTemplate 并更改UIButton 的色调为白色，同时还在字符串前添加两个空格：“Back”。这将导致类似于导航栏后退按钮的安静内容，图像在大小和位置方面可能会更好。

编辑代码：

     func addBackButton() {


            let backButtonImage = UIImage(named: "BackButton.png")?.withRenderingMode(.alwaysTemplate)

            let backButton = UIButton(type: .custom)
            backButton.setImage(backButtonImage, for: .normal) 
            backButton.tintColor = .white
            backButton.setTitle("  Back", for: .normal)
            backButton.setTitleColor(.white, for: .normal)
            backButton.addTarget(self, action: #selector(self.backAction(_:)), for: .touchUpInside)

            self.navigationItem.leftBarButtonItem = UIBarButtonItem(customView: backButton)


}

Answer 4

更新 Swift 4.2 - 感谢 sam bing 和 silentbeep

对一些颜色和动作的选择器进行了一些修改。

    override func viewDidLoad() {
        super.viewDidLoad()
        self.view.backgroundColor = .blue
        self.navigationItem.title = title
        self.navigationController?.navigationBar.barTintColor = .white
        self.navigationItem.leftBarButtonItem = UIBarButtonItem(customView: makeBackButton())
    }

    func makeBackButton() -> UIButton {
        let backButtonImage = UIImage(named: "backbutton")?.withRenderingMode(.alwaysTemplate)
        let backButton = UIButton(type: .custom)
        backButton.setImage(backButtonImage, for: .normal)
        backButton.tintColor = .blue
        backButton.setTitle("  Back", for: .normal)
        backButton.setTitleColor(.blue, for: .normal)
        backButton.addTarget(self, action: #selector(self.backButtonPressed), for: .touchUpInside)
        return backButton
    }

    @objc func backButtonPressed() {
        dismiss(animated: true, completion: nil)
//        navigationController?.popViewController(animated: true)
    }

Answer 5

我更改了所选答案的最后一行代码，它对我有用。

override func viewDidLoad() {
    super.viewDidLoad()

    addBackButton()
}

func addBackButton() {
    let backButton = UIButton(type: .custom)
    backButton.setImage(UIImage(named: "BackButton.png"), for: .normal) // Image can be downloaded from here below link
    backButton.setTitle("Back", for: .normal)
    backButton.setTitleColor(backButton.tintColor, for: .normal) // You can change the TitleColor
    backButton.addTarget(self, action: #selector(self.backAction(_:)), for: .touchUpInside)

    self.navigationItem.leftBarButtonItem = UIBarButtonItem(customView: backButton)
}

@IBAction func backAction(_ sender: UIButton) {
   let _ = self.dismiss(animated: true, completion: nil)
}

Answer 6

为了将来的搜索，我想补充一点，您现在可以通过以下代码使用默认图标：

override public func viewDidLoad() {
    // create chevron image
    let config = UIImage.SymbolConfiguration(pointSize: 25.0, weight: .medium, scale: .medium)
    let image = UIImage(systemName: "chevron.left", withConfiguration: config)

    // create back button
    let backButton = UIButton(type: .custom)
    backButton.addTarget(self, action: #selector(self.close(_:)), for: .touchUpInside)
    backButton.setImage(image, for: .normal)
    backButton.setTitle("Back", for: .normal)
    backButton.setTitleColor(backButton.tintColor, for: .normal)
    self.navigationItem.leftBarButtonItem = UIBarButtonItem(customView: backButton)
}

@IBAction func close(_ sender: UIButton) {
    self.navigationController?.dismiss(animated: true, completion: nil)
}

Answer 7

Swift 5

override func viewDidLoad() {
            super.viewDidLoad()
            let backbutton = UIButton(type: .custom)
            backbutton.setImage(UIImage(named: "BackButton.png"), for: .normal) // Image can be downloaded from here below link
            backbutton.setTitle("Back", for: .normal)
            backbutton.setTitleColor(backbutton.tintColor, for: .normal) // You can change the TitleColor
            backbutton.addTarget(self, action: Selector(("backAction")), for: .touchUpInside)
    
            self.navigationItem.leftBarButtonItem = UIBarButtonItem(customView: backbutton)
        }
    
        func backAction() -> Void {
            self.navigationController?.popViewController(animated: true)
        }

如何以编程方式在 Swift 中创建 "Back" UIBarButton 项目？

How to programmatically create a "Back" UIBarButton item in Swift?

uibarbuttonitem

ios

swift