ios - [UI按钮设置文本:]: unrecognized selector sent to instance

Question

我已经阅读了有关此问题的几个答案，但似乎找不到适用于我的代码的答案。当我分配“myLabel”的“text”成员(如下)时，我得到:“[UIButton setText:]:无法识别的选择器发送到实例......”程序编译正常，但在遇到赋值语句时崩溃。

但是我可以分配甚至打印出同一对象的背景颜色。关于我做错了什么有什么想法吗？

//******** 导入 UIKit

class ViewController: UIViewController {

//*********  Button 1 *********//


@IBOutlet weak var lbl1: UILabel!


@IBAction func btn1(sender: AnyObject) {

    nextColorFor1++
    makeColor (self.lbl1, nextColor: nextColor1)

}

//****  Button 2  **********//


@IBOutlet weak var lbl2: UILabel!

@IBAction func btn2(sender: AnyObject) {

    nextColorFor2++
    makeColor (self.lbl2, nextColor: nextColorFor2)

}

//********************************//

func makeColor (myLabel:UILabel, nextColor:Int)
{
    switch nextColor
    {
    case 0: myLabel.backgroundColor = UIColor(red: 0.1, green: 0, blue: 0, alpha: 0.1)
    case 1: myLabel.backgroundColor = UIColor(red: 0.2, green: 0, blue: 0, alpha: 0.2)
    case 2: myLabel.backgroundColor = UIColor(red: 0.3, green: 0, blue: 0, alpha: 0.3)
    case 3: myLabel.backgroundColor = UIColor(red: 0.4, green: 0, blue: 0, alpha: 0.4)
    case 4: myLabel.backgroundColor = UIColor(red: 0.5, green: 0, blue: 0, alpha: 0.5)
    default: print("end of colors")
    }

    print(myLabel.backgroundColor)
    myLabel.text = "4"  <<< --- This is where the crask occurs
}


override func viewDidLoad() {


    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

}

}

Answer 1

您似乎已将 UIButton(位于 Storyboard或 xib 上)作为代码中的 UILabel 连接，并且您试图将其视为标签。确保更换 IB 上的标签按钮，它就会起作用。