How do you add a button to a UIPickerView?

Question

How do you add a single button to UIPickerView that can be used to dismiss or hide the PickerView?

I found a few solutions to these problems and many did not seem to come up with the answer I wanted. This question was the closest I could find to what I was asking, but it is very outdated so I wanted to display my solution. I have a subclass of UIPickerView that I wanted to add a UIButton to be able to dismiss on. I do not want a UIPickerView with a UIToolBar inside.

The below image describes exactly what I am looking for where the done button is added to my subclass of UIPickerView

It may seem trivial that all you need to do is add a UIButton to the UIPickerView and add a target to call on a method, because I also want the PickerView to respond to user selection on the rows, pressing the Done button caused no response

Answer 1

Create subclass of UIView as such

class CustomViewWithPicker: UIView {
    
    let picker = UIPickerView(frame: .zero)
    let pickerTitle = UILabel(frame: .zero)
    let button = UIButton(frame: .zero)
    
    let title: String = "Picker Title"
    let buttonName: String = "Button"
    
    override init(frame: CGRect) {
        super.init(frame: frame)
        didLoad()
    }
    
    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        didLoad()
    }
    
    func didLoad() {
        
        self.addSubview(picker)
        self.addSubview(pickerTitle)
        self.addSubview(button)
        
        picker.backgroundColor = .tertiarySystemBackground
        picker.layer.cornerRadius = 20
        picker.frame = .zero
        
        pickerTitle.text = title
        pickerTitle.font = .boldSystemFont(ofSize: 22)
        pickerTitle.textAlignment = .center
        pickerTitle.backgroundColor = .tertiarySystemBackground
        
        button.setTitle(buttonName, for: .normal)
        button.contentHorizontalAlignment = .right
        button.contentVerticalAlignment = .top
        button.isSelected = true
        
        self.updateConstraints()
    }
    
    override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
        if self.point(inside: point, with: event) {
            return super.hitTest(point, with: event)
        }
        guard isUserInteractionEnabled, !isHidden, alpha > 0 else {
            return nil
        }
        
        for subview in subviews.reversed() {
            let convertedPoint = subview.convert(point, from: self)
            if let hitView = subview.hitTest(convertedPoint, with: event) {
                return hitView
            }
        }
        return nil
    }
    
    override func layoutSubviews() {
        super.layoutSubviews()
    }
    
    override func updateConstraints() {
        // Make Constraints ...
    }
}

In the ViewController conform to UIPickerViewDelegate and UIPickerViewDataSource

class MyViewController : UIViewController, UIPickerViewDelegate, UIPickerViewDataSource, UIGestureRecognizerDelegate {
    
    let customView = CustomViewWithPicker()
    let labels = ["label0", "label1", "label2", "label3", "label4", "label5"]
    var selectedRow = 0

    override func viewDidLoad() {
        super.viewDidLoad()
        
        customView.picker.delegate = self
        customView.picker.dataSource = self

        customView.button.addTarget(self, action: #selector(doneButtonTapped(_:)), for: .touchUpInside)
        
        self.view.addSubview(customView)
        
    }
    
    func numberOfComponents(in pickerView: UIPickerView) -> Int {
        1
    }
    
    func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
        return labels.count
    }
    
    func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
        return labels[row]
    }
    
    func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
        selectedRow = row
    }
    
    @objc func doneButtonTapped(_ selectedButton: UIButton) {
        if selectedButton.isSelected {
            print("Done Button Tapped")
        }
    }
}

I looked far and wide for a UIPickerView implementation that did not rely on UIToolBar to detect a tap on the button to no avail.

Thank you to Duncan C. for the input and advice