如何在swift 3中使用addTarget方法

Question

这是我的button对象

    let loginRegisterButton:UIButton = {
    let button = UIButton(type: .system)
    button.backgroundColor = UIColor(r: 50 , g: 80, b: 130)
    button.setTitle("Register", for: .normal)
    button.translatesAutoresizingMaskIntoConstraints = false
    button.setTitleColor(.white, for: .normal)
    button.addTarget(self, action:#selector(handleRegister), for: .touchUpInside)
    return button
}()

这是我的功能

    func handleRegister(){

    FIRAuth.auth()?.createUser(withEmail: email, password: password,completion: { (user, error) in

        if error != nil
        { print("Error Occured")}

        else
        {print("Successfully Authenticated")}
    })        
}

我收到编译错误,如果addTarget删除它成功编译

Answer 1

是的,如果没有参数,请不要添加"()"

button.addTarget(self, action:#selector(handleRegister), for: .touchUpInside). 

如果你想得到发件人

button.addTarget(self, action:#selector(handleRegister(_:)), for: .touchUpInside). 

func handleRegister(sender: UIButton){
   //...
}

编辑:

button.addTarget(self, action:#selector(handleRegister(_:)), for: .touchUpInside)

不再有效,你需要_在选择器中替换你在函数头中使用的变量名,在这种情况下它将是sender,所以工作代码变为:

button.addTarget(self, action:#selector(handleRegister(sender:)), for: .touchUpInside)

Answer 2

尝试使用Swift 4

buttonSection.addTarget(self, action: #selector(actionWithParam(_:)), for: .touchUpInside)
@objc func actionWithParam(sender: UIButton){
    //...
}

buttonSection.addTarget(self, action: #selector(actionWithoutParam), for: .touchUpInside)
@objc func actionWithoutParam(){
    //...
}

Answer 3

试试这个

button.addTarget(self, action:#selector(handleRegister()), for: .touchUpInside). 

只需添加带有方法名称的括号即可.

你也可以参考链接:'CustomButton'类型的值没有成员'touchDown'

Answer 4

尝试使用swift 3

cell.TaxToolTips.tag = indexPath.row
        cell.TaxToolTips.addTarget(self, action: #selector(InheritanceTaxViewController.displayToolTipDetails(_:)), for:.touchUpInside)


 @objc func displayToolTipDetails(_ sender : UIButton) {
        print(sender.tag)
        let tooltipString = TaxToolTipsArray[sender.tag]
        self.displayMyAlertMessage(userMessage: tooltipString, status: 202)    
}

Answer 5

  let button: UIButton = UIButton()
    button.setImage(UIImage(named:"imagename"), for: .normal)
    button.addTarget(self, action:#selector(YourClassName.backAction(_sender:)), for: .touchUpInside)

    button.frame = CGRect.init(x: 5, y: 100, width: 45, height: 45)
    view.addSubview(button)

    @objc public func backAction(_sender: UIButton) {

    }