当用户触摸已选择的行时，如何隐藏UIPIckerView

Question

我在我的代码中有多个UIPickerView，让我们假设用户无意中打开PickerView，但希望保持选中同一行，就像我为用户触摸已经选择的行，选择器是否隐藏？

我试过这个：UIPicker detect tap/touch on currently selected row，但我无法让它工作。

---编辑---

我会尽量做得更具体。我是编程和Swift语言的初学者。

这是我ViewController.swift

import UIKit 

class ViewController: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource { 

@IBOutlet weak var colorLabel: UILabel! 
@IBOutlet weak var sizeLabel: UILabel! 

@IBOutlet weak var colorButton: UIButton! 
@IBOutlet weak var sizeButton: UIButton! 

@IBOutlet weak var resultButton: UIButton! 

@IBOutlet weak var colorPickerView: UIPickerView! = UIPickerView() 
@IBOutlet weak var sizePickerView: UIPickerView! = UIPickerView() 

var colorPickerData = ["Blue", "Red"] 
var sizePickerData = ["Small", "Big"] 

var descri = String() 
var resultadoImagem = UIImage() 

override func viewDidLoad() { 
    super.viewDidLoad() 


    colorPickerView.isHidden = true 
    sizePickerView.isHidden = true 


    self.colorPickerView.delegate = self 
    self.colorPickerView.dataSource = self 

    self.sizePickerView.delegate = self 
    self.sizePickerView.dataSource = self 


    colorLabel.text = colorPickerData[0] 
    sizeLabel.text = sizePickerData[0] 
} 

override func didReceiveMemoryWarning() { 

    super.didReceiveMemoryWarning() 

} 

func numberOfComponents(in pickerView: UIPickerView) -> Int { 
    return 1 
} 

func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int { 
    if pickerView.tag == 1 { 
     return colorPickerData.count 
    } else if pickerView.tag == 2 { 
     return sizePickerData.count 
    } 
    return 0 
} 

func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? { 
    if pickerView.tag == 1 { 
     return "\(colorPickerData[row])" 
    } else if pickerView.tag == 2 { 
     return "\(sizePickerData[row])" 
    } 
    return "" 
} 

func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) { 
    if pickerView.tag == 1 { 
     colorLabel.text = colorPickerData[row] 
     colorPickerView.isHidden = true 
    } else if pickerView.tag == 2 { 
     sizeLabel.text = sizePickerData[row] 
     sizePickerView.isHidden = true 
    } 
} 

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) { 
    colorPickerView.isHidden = true 
    sizePickerView.isHidden = true 
} 

@IBAction func colorButton(_ sender: Any) { 
    colorPickerView.isHidden = !colorPickerView.isHidden 
} 

@IBAction func sizeButton(_ sender: Any) { 
    sizePickerView.isHidden = !sizePickerView.isHidden 
} 

@IBAction func resultButton(_ sender: Any) { 
    if (colorLabel.text == "Blue") 
     && (sizeLabel.text == "Big") { resultadoImagem = UIImage(named: "blue-big.png")!; descri = "BLUE"} 
    else if (colorLabel.text == "Blue") 
     && (sizeLabel.text == "Small") { resultadoImagem = UIImage(named: "blue-small.png)!; descri = "BLUE"} 
    else if (colorLabel.text == "Red") 
     && (sizeLabel.text == "Big") { resultadoImagem = UIImage(named: "red-big.png")!; descri = "RED"} 
    else if (colorLabel.text == "Red") 
     && (sizeLabel.text == "Small") { resultadoImagem = UIImage(named: "red-small.png")!; descri = "RED"} 

    self.performSegue(withIdentifier: "resultSegue", sender: nil) 
} 

override func prepare(for segue: UIStoryboardSegue, sender: Any?) { 
    if segue.identifier == "resultSegue" { 
     let DestViewController : SecondViewController = segue.destination as! SecondViewController 

    DestViewController.descText = descri 
    DestViewController.resultPhoto = resultadoImagem 
    } 
} 

} 

此代码的伟大工程，当我打的“结果”按钮，它会转到SecondViewController并显示照片和说明。

我的困难是，colorPickerView打开并选中数据“Blue”，就像sizerPickerView默认打开数据“Small”一样。我希望pickerView在用户触摸已经选择的数据时关闭/隐藏。

Answer 1

顺应类UIGestureRecognizerDelegate协议

class ViewController: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource, UIGestureRecognizerDelegate { 
    // ... 
} 

添加UITapGestureRecognizer您colorPickerView

let tap = UITapGestureRecognizer(target: self, action: #selector(self.tapAction(_:))) 
tap.cancelsTouchesInView = false 
tap.delegate = self 
colorPickerView.addGestureRecognizer(tap) 

实现UIGestureRecognizerDelegate方法

func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool { 
    return true 
} 

最后落实tapAction

func tapAction(_ tapRecognizer:UITapGestureRecognizer) { 
    if tapRecognizer.state == .ended { 
     let rowHeight : CGFloat = colorPickerView.rowSize(forComponent: 0).height 
     let selectedRowFrame: CGRect = colorPickerView.bounds.insetBy(dx: 0.0, dy: (colorPickerView.frame.height - rowHeight)/2.0) 
     let userTappedOnSelectedRow = selectedRowFrame.contains(tapRecognizer.location(in: colorPickerView)) 
     if (userTappedOnSelectedRow){ 
      let selectedRow = colorPickerView.selectedRow(inComponent: 0) 
      //do whatever you want here 
     } 
    } 
} 

使用sizerPickerView复制步骤2和4以扩展功能。