Using UIButton within the cell of UIPickerView

Question

In my app I have a settings page, and I would like a UIPickerView that works as a check box(lists items and you can enable or disable them). I've looked up different solutions and all I could find was using viewForRow and using UIButton. I am able to add the buttons and it looks good but the buttons don't seem to be tappable.

Heres my implementation:

func pickerView(_ pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusing view: UIView?) -> UIView{
    let button = UIButton(type: .system)
    button.addTarget(self, action: #selector(screenSelectorButtonPress(_:)), for: .touchUpInside)
    button.tag = 0
    if row == 0{
        button.setTitle(Array3[row], for: .normal)
    }else{
        button.setTitle("\u{2610} \(Array3[row])", for: .normal)
    }
    return button
}

@objc func screenSelectorButtonPress(_ sender:UIButton!){
    print("test")
}

The cells all populate properly but tapping them does nothing. The functionality that I want is exactly as seen here in safari.

Is there another way to do this or am I doing something wrong with the button? Also yes I could just use switches but our Android version of the app uses a check list like how safari does and we would like to keep it consistent.

Shehata Gamal · Accepted Answer · 2018-07-19T22:23:52.873

You should implement

func pickerView(_ pickerView: UIPickerView, 
        didSelectRow row: Int, 
         inComponent component: Int)

//

self.pickerView.delegate = self

//

class ViewController: UIViewController , UIPickerViewDelegate,UIPickerViewDataSource , UIGestureRecognizerDelegate {

    let pickerView = UIPickerView()

    override func viewDidLoad() {

        super.viewDidLoad()

        pickerView.frame = CGRect(x: 0, y: 30, width: self.view.frame.width, height: 300)

        pickerView.delegate = self

        pickerView.dataSource = self

        view.addSubview(pickerView)

        let tap = UITapGestureRecognizer(target: self, action: #selector(pickerTapped))

        tap.delegate = self

        pickerView.addGestureRecognizer(tap)

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

    func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
        return Array3.count
    }

    func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
        print(row)
    }


    func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {

        if row == 0 {

            return Array3[row]
        }
        else {

            return "\u{2610} \(Array3[row])"
        }

    }


    @objc func pickerTapped(tapRecognizer: UITapGestureRecognizer) {
        if tapRecognizer.state == .ended {
            let rowHeight = self.pickerView.rowSize(forComponent: 0).height
            let selectedRowFrame = self.pickerView.bounds.insetBy(dx: 0, dy: (self.pickerView.frame.height - rowHeight) / 2)
            let userTappedOnSelectedRow = selectedRowFrame.contains(tapRecognizer.location(in: self.pickerView))
            if userTappedOnSelectedRow {
                let selectedRow = self.pickerView.selectedRow(inComponent: 0)
                pickerView(self.pickerView, didSelectRow: selectedRow, inComponent: 0)
            }
        }
    }


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


}

ok I will give this a shot. I wouldn't need UIButtons then I don't think — Mumphus, Jul 19 '18 at 21:52
**note:** according to **UIPickerView** logic this method is triggered on dragging the spinner to an item , tapping has not existence — Shehata Gamal, Jul 19 '18 at 22:01
Hmmm that wont seem smooth for my app. How do they do it in the safari app? — Mumphus, Jul 19 '18 at 22:02
In addition to the method in answer implement this https://stackoverflow.com/a/48659244/5820010 ,, this will trigger it on tap — Shehata Gamal, Jul 19 '18 at 22:08

Using UIButton within the cell of UIPickerView

1 Answers1