ios - 一键两个目标

Question

我有一个自定义的解开按钮，我也添加了两个目标。如果文本字段为空，则一个目标将起作用，但如果文本字段不为空，则另一个目标将起作用。但是两个目标同时作用于单个按钮。有人可以帮助我并向我解释为什么。

override func viewDidLoad() {
    super.viewDidLoad()
    FirstName.delegate = self
    LastName.delegate = self
    FirstName.addTarget(self, action:"edited", for:UIControlEvents.allEditingEvents)
    LastName.addTarget(self, action:"edited", for:UIControlEvents.allEditingEvents)
    // Do any additional setup after loading the view.
    if FirstName.text?.isEmpty == true || LastName.text == "" {
        ProgressButton.setImage(UIImage(named: "Skip"), for: .normal)
        ProgressButton.contentEdgeInsets = UIEdgeInsetsMake(0,0,0,0)
        ProgressButton.addTarget(self, action: #selector(Skip(_sender:)), for: UIControlEvents.touchUpInside)
    } else {
        ProgressButton.setImage(UIImage(named: "Right2"), for: .normal)
        ProgressButton.contentEdgeInsets = UIEdgeInsetsMake(20,31,24,0)
        ProgressButton.addTarget(self, action: #selector(Continue(_sender:)), for: UIControlEvents.touchUpInside)
    }
}

func edited() {
    if FirstName.text?.isEmpty == true || LastName.text == "" {
        ProgressButton.setImage(UIImage(named: "Skip"), for: .normal)
        ProgressButton.contentEdgeInsets = UIEdgeInsetsMake(0,0,0,0)
        ProgressButton.addTarget(self, action: #selector(Skip(_sender:)), for: UIControlEvents.touchUpInside)
    } else {
        ProgressButton.setImage(UIImage(named: "Right2"), for: .normal)
        ProgressButton.contentEdgeInsets = UIEdgeInsetsMake(20,31,24,0)
        ProgressButton.addTarget(self, action: #selector(Continue(_sender:)), for: UIControlEvents.touchUpInside)
    }
}

func Continue(_sender: ABProgressButton!) {
    FirstName.resignFirstResponder()
    LastName.resignFirstResponder()
        // Delay the dismissal by 5 seconds
        let delay = 0.85 * Double(NSEC_PER_SEC)
        var time = DispatchTime.now() + Double(Int64(delay)) / Double(NSEC_PER_SEC)
        DispatchQueue.main.asyncAfter(deadline: time, execute: {

            self.performSegue(withIdentifier: "ToViewController#2", sender: nil)

        })

}

func Skip(_sender: ABProgressButton!) {
    FirstName.resignFirstResponder()
    LastName.resignFirstResponder()
    self.performSegue(withIdentifier: "ToViewController#2", sender: nil)
}

Answer 1

您需要为已安装在按钮上的操作调用 removeTarget(_:action:for:)。检查 addTarget(_:action:for:) header 中的注释。