Question

我尝试在给定初始值的swift中动态生成按钮，大小为8的数组将生成8个按钮。

然而，即使代码有效，每当我点击任何生成的按钮时，应用程序会立即崩溃并显示错误代码＆＃34;线程1信号SIGABRT＆＃34;并且控制台读取＆＃34; libc ++ abi.dylib：以NSException＆＃34;类型的未捕获异常终止。

然后我指向包含＆＃34;类AppDelegate的行：UIResponder，UIApplicationDelegate {＆＃34;在AppDelegate.swift中。

我已尝试过在其他类似问题中看到的建议，但无济于事，请参阅下面的代码

func generateButtons (){

    var numberOfVillains = ["1", "2", "3", "4", "5", "6", "7",  "8", "9", "10"]
    var buttonY: CGFloat = 126  // our Starting Offset, could be 0
    for number in numberOfVillains {
        let segmentController = UISegmentedControl()
        //let villainButton = UISegmentedControl(frame: CGRect(x: 50, y: buttonY, width: 50, height: 30)){
        buttonY = buttonY + 40  // we are going to space these UIButtons 50px apart
        segmentController.frame = CGRect(x:160, y:buttonY, width: 100,height:  30)
        //segment frame size
        segmentController.insertSegment(withTitle: "Off", at: 0, animated: true)
        //inserting new segment at index 0
        segmentController.insertSegment(withTitle: "On", at: 1, animated: true)
        //inserting new segment at index 1
        segmentController.backgroundColor = UIColor.white
        //setting the background color of the segment controller
        segmentController.selectedSegmentIndex = 0
        //setting the segment which is initially selected
        segmentController.addTarget(self, action: Selector(("segment:")), for: UIControlEvents.valueChanged)
        //calling the selector method
        self.view.addSubview(segmentController)
        //adding the view as subview of the segment comntroller w.r.t. main view controller
    }

}

func buttonPressed(sender: UISegmentedControl!) {
    print("ButtonIsSelected")
}

Answer 1

您正在按钮上设置选择器的目标（（＆＃34;段：＆＃34;））。但是，您为处理点击而添加的方法称为buttonPressed（）

将选择器（（＆＃34;段：＆＃34;））更改为选择器（＆＃34; buttonPressed：＆＃34;），这应解决问题

Answer 2

事情需要看起来像这样：

class ViewController: UIViewController {

  func generateButtons (){
    ...
  }

  @objc func buttonPressed(sender: UISegmentedControl!) {
    print("ButtonIsSelected")
  }

}

而不是这样：

class ViewController: UIViewController {

  func generateButtons (){
    ...
  }

}

@objc func buttonPressed(sender: UISegmentedControl!) {
  print("ButtonIsSelected")
}

另外，要使编译器警告静音，请尝试更改行：

segmentController.addTarget(self, action: Selector(("buttonPressed:")), for: UIControlEvents.valueChanged)

为：

segmentController.addTarget(self, action: #selector(buttonPressed), for: UIControlEvents.valueChanged)

Answer 3

我认为我已经发现了问题，显然你为生成的按钮引用的函数不需要包含“：”，也不包含任何括号，如果它不包含任何参数，那么正确的格式是

segmentController.addTarget(self, action: #selector(ViewController.buttonPressed), for: .valueChanged)

而不是

segmentController.addTarget(self, action: Selector(("buttonPressed:")), for: UIControlEvents.valueChanged)'

单击时以编程方式生成的按钮崩溃应用程序。

3 个答案: