swiftuipickerviewswift3xcode8uipickerviewdatasource

Xcode 8 / Swift 3 : Simple UIPicker code not working


I have protocols:

class ViewController: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource {

I have data:

let muteForPickerData = ["minute(s)","hour(s)"]

In viewDidLoad I have:

muteForPicker.delegate = self
muteForPicker.dataSource = self

Then I have required methods:

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

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

func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
            return muteForPickerData[row]
        }

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

Still I get

type viewcontroller does not conform to protocol UIPickerViewDataSource


Solution

  • UIPickerViewDataSource method numberOfComponentsInPickerView is changed in Swift 3 like this that is the reason you are getting this error.

    func numberOfComponents(in pickerView: UIPickerView) -> Int {
        return 1
    }
    
    func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
        return muteForPickerData.count
    }
    
    func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
        return muteForPickerData[row]
    }
    
    func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    
    }
    

    For more detail read Apple Documentation on UIPickerView.

    Note: You need to also add _ as first parameter label same like other methods in your UIPickerViewDelegate method that is titleForRow and didSelectRow.