如何确定哪个文本字段是活跃的 [英] How to determine which textfield is active swift

问题描述

我无法弄清楚哪个 UITextField 当前有效，所以如果他们在 UIBarButtonItem 。这是我的代码。有一个带有 UIPickerView ， UIToolBar 和两个条形按钮项的视图。取消项目有一个动作，只会清除其文本我无法弄清楚如何获得正确的 UITextField 。

I cant figure out which UITextField is currently active so i can clear its text if they hit cancel on a UIBarButtonItem. Here is my code. There is a view with a UIPickerView,UIToolBar and two bar button items. The cancel item has an action that will clear its text only i cant figure out how to get the correct UITextField.

我试过这两个：

@IBAction func cancelText(sender: AnyObject) {


    if self.truckYear.editing == true{

        println("truckYear")

        clearText(self.truckYear)
    } else if self.truckMake.editing == true{

        clearText(self.truckMake)
    }
}
@IBAction func doneText(sender: AnyObject) {

    pickerView.hidden = true
}


func clearText(textField:UITextField){

    println("in clear text")

    textField.text = nil
}

并且：

@IBAction func cancelText(sender: AnyObject) {


    if self.truckYear.isFirstResponder(){

        println("truckYear")

        clearText(self.truckYear)
    } else if self.truckMake.isFirstResponder(){

        clearText(self.truckMake)
    }
}
@IBAction func doneText(sender: AnyObject) {

    pickerView.hidden = true
}


func clearText(textField:UITextField){

    println("in clear text")

    textField.text = nil
}

推荐答案

您可以在类中声明 UITextField 属性，并在 textFieldDidBeginEditing <中为其指定当前文本字段/ code>。
然后你可以随时调用这个文本字段。

You can declare a UITextField property in your class, and assign the current text field to it in textFieldDidBeginEditing. Then you can just call this text field whenever you need to.

class ViewController : UIViewController, UITextFieldDelegate {

   var activeTextField = UITextField()

   // Assign the newly active text field to your activeTextField variable
   func textFieldDidBeginEditing(textField: UITextField) {

        self.activeTextField = textField
   }

   // Call activeTextField whenever you need to
   func anotherMethod() {

       // self.activeTextField.text is an optional, we safely unwrap it here
       if let activeTextFieldText = self.activeTextField.text {
             print("Active text field's text: \(activeTextFieldText)")
             return;
       }

       print("Active text field is empty")
   }
}

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