如何为所有 PickerViews 创建单个完成和取消按钮？

Question

我想要实现的是完成按钮应该将特定的选择器视图行值保存到特定的 UITextField。 我在一个视图控制器中有两个pickerview。

override func viewDidLoad() {
     textField1.inputView = pickerview1
     textField2.inputView = pickerview2
     let toolBar = UIToolbar()
     toolBar.barStyle = UIBarStyle.default
     toolBar.isTranslucent = true
     toolBar.sizeToFit()
     let cancelButton = UIBarButtonItem(barButtonSystemItem: UIBarButtonItem.SystemItem.cancel, target: nil, action: #selector(self.cancelPicker))
     let spaceButton = UIBarButtonItem(barButtonSystemItem: UIBarButtonItem.SystemItem.flexibleSpace, target: nil, action: nil)
     let doneButton = UIBarButtonItem(title: "Done", style: UIBarButtonItem.Style.done, target: self, action: #selector(self.donePicker))
     toolBar.setItems([cancelButton, spaceButton, doneButton], animated: false)
     toolBar.isUserInteractionEnabled = true
     textField1.inputAccessoryView = toolBar
     textField2.inputAccessoryView = toolBar   
    }
  @objc func cancelPicker() {
     //cancel that particular pickerview
   }
    @objc func donePicker() {
      // get that particular value in textfield
    }

文本字段和选择器视图都作为 IBOutlets 连接。

Answer 1

您可以检测哪个文本字段已获得焦点并存储对它的引用（我存储了它的索引），当您点击工具栏上的完成或取消按钮时，您可以更改该特定文本字段的值。

我将您的代码更改如下。

class ViewController: UIViewController , UITextFieldDelegate {
    
    @IBOutlet var textFields : [UITextField]!
    @IBOutlet var pickerviews : [UIPickerView]!
    
    
    let array = ["one" , "two" , "three"]
    
    var selectedTextfieldIndex : Int?
    var selectedTitle : String?
    
    override func viewDidLoad() {
        
        for pickerview in pickerviews
        {
            pickerview.delegate = self
            pickerview.dataSource = self
        }
        
        for textfield in textFields
        {
            textfield.delegate = self
        }
        
        
        let toolBar = UIToolbar()
        toolBar.barStyle = UIBarStyle.default
        toolBar.isTranslucent = true
        toolBar.sizeToFit()
        let cancelButton = UIBarButtonItem(barButtonSystemItem: UIBarButtonItem.SystemItem.cancel, target: nil, action: #selector(self.cancelPicker))
        let spaceButton = UIBarButtonItem(barButtonSystemItem: UIBarButtonItem.SystemItem.flexibleSpace, target: nil, action: nil)
        let doneButton = UIBarButtonItem(title: "Done", style: UIBarButtonItem.Style.done, target: self, action: #selector(self.donePicker))
        toolBar.setItems([cancelButton, spaceButton, doneButton], animated: false)
        toolBar.isUserInteractionEnabled = true
        textFields[0].inputAccessoryView = toolBar
        textFields[1].inputAccessoryView = toolBar
        
        
        textFields[0].inputView = pickerviews[0]
        textFields[1].inputView = pickerviews[1]
    }
    
    func textFieldDidBeginEditing(_ textField: UITextField) {
        
        for ( index , item) in textFields.enumerated()
        {
            if textField == item
            {
                selectedTextfieldIndex = index
            }
        }
    }
    
    
    @objc func cancelPicker() {
        
        guard let index = selectedTextfieldIndex else { return }

        textFields[index].text = nil
        selectedTextfieldIndex = nil
        textFields[index].endEditing(true)

    }
    
    @objc func donePicker() {
        
        guard let index = selectedTextfieldIndex else { return }
        
        textFields[index].text = selectedTitle
        selectedTextfieldIndex = nil
        textFields[index].endEditing(true)

    }
    
}



extension ViewController : UIPickerViewDelegate , UIPickerViewDataSource
{
    func numberOfComponents(in pickerView: UIPickerView) -> Int {
        return 1
    }
    
    func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
        return array.count
    }
    
    func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
        return array[row]
    }
    
    func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
        self.selectedTitle = array[row]
    }
}