如何从选择器中读取数据（尝试了一些问题的答案，但仍未解决）

Question

所以我只想阅读我从选择器中选择的选项。我阅读了一些问题和答案，但无法使其正常运行。我一定做错了。所以有我的代码：

import UIKit
import Firebase
import FirebaseFirestore

class AddItemViewController: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource {

    @IBOutlet weak var itemNameField: UITextField!
    @IBOutlet weak var storeNameField: UITextField!
    @IBOutlet weak var dateOfPurchaseField: UIDatePicker!
    @IBOutlet weak var guaranteePeriodField: UIPickerView!
    let guaranteePeriodData = ["1 Year", "2 Years", "3 Years", "4 Years", "5 Years", "6 Years"]


    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.

        guaranteePeriodField.delegate = self
        guaranteePeriodField.dataSource = self
    }

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

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

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

    @IBAction func addItemButtonTouched(_ sender: Any) {
        let db = Firestore.firestore()

        guard let uid = Auth.auth().currentUser?.uid,
        let name = itemNameField.text else {
                return // return control to the caller or do something else to indicate access denied
        }
        let store = storeNameField.text
        let dateOfPurchase = dateOfPurchaseField.date
        let guaranteePeriod = guaranteePeriodData[guaranteePeriodField.selectedRow(inComponent: print(guaranteePeriod))]
        db.collection("recipes").addDocument(data: ["name": name, "uid": uid, "store": store, "dateOfPurchase": dateOfPurchase, "guaranteePeriod": guaranteePeriod])
        displayAlertMessage(alertTitle: "Success", alertMessage: "New item added successfully.", dismiss: true)
    }

我想使其尽可能简单，我只需要读取值，然后将其保存到firebase。

Answer 1

您可以使用以下方法读取所选值

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

Answer 2

您需要像这样在delegate中设置dataSource的UIPickerView和viewDidLoad：

guaranteePeriodField?.delegate = self
guaranteePeriodField?.dataSource = self