Simple, genericized Swift object for backing UIPickerViews. All you need is an array and a callback block and you're golden.

PickerHandler.swift

//  PickerHandler.swift
//  Created by Jake Hawken on 8/27/19.

import Foundation
import UIKit

class PickerHandler<T: CustomStringConvertible> {
    
    typealias ItemSelectionCallback = (T)->()
    private let implementation: PickerHandlerImplementation<T>
    
    init(items: [T], selectionCallback: ItemSelectionCallback?) {
        implementation = PickerHandlerImplementation(items: items, selectionCallback: selectionCallback)
    }
    
    func becomeHandlerFor(picker: UIPickerView) {
        picker.dataSource = implementation
        picker.delegate = implementation
    }
    
}

private class PickerHandlerImplementation<T: CustomStringConvertible>: NSObject, UIPickerViewDataSource, UIPickerViewDelegate {
    
    private let items: [T]
    private let itemSelectionCallback: PickerHandler<T>.ItemSelectionCallback?
    
    init(items: [T], selectionCallback: PickerHandler<T>.ItemSelectionCallback?) {
        self.items = items
        self.itemSelectionCallback = selectionCallback
        super.init()
    }
    
    func numberOfComponents(in pickerView: UIPickerView) -> Int {
        return 1
    }
    
    func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
        return items.count
    }
    
    func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
        return items[row].description
    }
    
    func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
        let item = items[row]
        itemSelectionCallback?(item)
    }
}