ios 如何在swift 3中以编程方式为barButtonItem设置动作？

how to programmatically set action for barButtonItem in swift 3?

提问by Bhanupriya

Here is what I used previously,

这是我之前用的

var barButtonItem = UIBarButtonItem(image: backImgs, style: UIBarButtonItemStyle.plain, target: self, action: Selector("menuButtonTapped:"))

But there is some syntax changes for Swift 3.

但是 Swift 3 有一些语法变化。

回答by Tony Vincent

ex:-

前任：-

navigationItem.rightBarButtonItem = UIBarButtonItem(title: "Add", style: .plain, target: self, action: #selector(addTapped))

回答by flame3

Summarize the mostly used method in Swift 3 for adding action to a barButton.

总结 Swift 3 中最常用的向 barButton 添加动作的方法。

1. Barbutton with text

   navigationItem.rightBarButtonItem = UIBarButtonItem(title: "Add", style: .plain, target: self, action: #selector(addTapped))
   

2. BarButton with your own image

   navigationItem.rightBarButtonItem = UIBarButtonItem(image: UIImage(named:"add"), style: .plain, target: self, action: #selector(addTapped))
   

3. BarButton with system image

   navigationItem.rightBarButtonItem = UIBarButtonItem(barButtonSystemItem: .add, target: self, action: #selector(addTapped))
   

1. 带有文本的条形按钮

   navigationItem.rightBarButtonItem = UIBarButtonItem(title: "Add", style: .plain, target: self, action: #selector(addTapped))
   

2. 带有您自己图像的 BarButton

   navigationItem.rightBarButtonItem = UIBarButtonItem(image: UIImage(named:"add"), style: .plain, target: self, action: #selector(addTapped))
   

3. 带有系统映像的 BarButton

   navigationItem.rightBarButtonItem = UIBarButtonItem(barButtonSystemItem: .add, target: self, action: #selector(addTapped))
   

回答by Onuray Sahin

If anyone is using customView:

如果有人正在使用customView：

barButtonItem.customView?.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(onBarButtonItemClicked)))

回答by Nirav D

You just need to change your selectorsyntax as of from Swift 3 you need to specify the first parameter name of method in your function call so change your selector like this.

您只需要更改selector从 Swift 3 开始的语法，您需要在函数调用中指定方法的第一个参数名称，以便像这样更改选择器。

#selector(menuButtonTapped(sender:))

And your method should be like this.

而你的方法应该是这样的。

func menuButtonTapped(sender: UIBarButtonItem) {

}

回答by Marco Aurelio Americo

One line of code on Swift 3 for iOS 10.1:

Swift 3 for iOS 10.1 的一行代码：

navigationController?.navigationBar.topItem?.rightBarButtonItem = UIBarButtonItem(title: "Add", style: .plain, target: self, action: nil)

回答by Mihail Salari

let barButtonItem = UIBarButtonItem(image: UIImage(named: "backImgs"),
                                            style: .plain,
                                            target: self,
                                            action: #selector(menuButtonTapped))

// Adding button to navigation bar (rightBarButtonItem or leftBarButtonItem)
self.navigationItem.rightBarButtonItem = barButtonItem

 // Private action
@objc fileprivate func menuButtonTapped() { // body method here }

回答by Mr. Tann

create an extension for barbutton item.

为 barbutton 项目创建一个扩展。

 extension UINavigationItem {
    func addSettingButtonOnRight(){
       let button = UIButton(type: .Custom)
       button.setTitle("setting", forState: .Normal)
       button.titleLabel?.font = UIFont.systemFontOfSize(15.0)
       button.layer.cornerRadius = 5
       button.backgroundColor = UIColor.grayColor()
       button.frame = CGRect(x: 0, y: 0, width: 100, height: 25)
       button.addTarget(self, action: #selector(gotSettingPage), forControlEvents: UIControlEvents.TouchUpInside)
       let barButton = UIBarButtonItem(customView: button)

       self.rightBarButtonItem = barButton
   }

   func gotSettingPage(){

   }
 }

And call it from viewDidLoad()

并从 viewDidLoad() 调用它

 self.navigationItem.addSettingButtonOnRight()

回答by Riajur Rahman

In Swift 3, you can add UIBarButtonItem like that,

在Swift 3 中，您可以像这样添加 UIBarButtonItem，

let addButton = UIBarButtonItem(image:UIImage(named:"your_icon_name"), style:.plain, target:self, action:#selector(YourControllerName.buttonAction(_:)))
addButton.tintColor = UIColor.white
self.navigationItem.rightBarButtonItem = addButton

And handle button action like that,

并像这样处理按钮动作，

func buttonAction(_ sender: UIBarButtonItem) {

}

Hope it helps.

希望能帮助到你。

回答by pankaj nigam

for Swift 4 add in viewDidLoad:

对于 Swift 4 添加viewDidLoad：

navigationItem.rightBarButtonItem = UIBarButtonItem(
    barButtonSystemItem: UIBarButtonSystemItem.add, 
    target: self, 
    action: #selector(addTransaction)
)

回答by ergunkocak

If someone is looking for a way to set the action on an existing button (Swift 5):

如果有人正在寻找一种在现有按钮上设置操作的方法 (Swift 5)：

if let leftBarButtonItem = navigationItem.leftBarButtonItem {
    leftBarButtonItem.target = self
    leftBarButtonItem.action = #selector(onBack(_:))
}


@IBAction func onBack(_ sender: AnyObject) {
    _ = navigationController?.popViewController(animated: true)
}