ios - 如何让 UIDatePicker 在 Swift 4 中更新文本字段和数据库

Question

在我的应用程序中，我有一个表单，它有一个文本字段，单击时会拉出一个 UIDatePicker。当我从 UIDatePicker 中选择新日期时，textField 不会更新。

调试时，似乎选择了新日期时未注册该操作，它只是在同一日期发送。

下面是我的代码（我计划在解决这个问题后重构/清理）

import UIKit
import RealmSwift

class ClientDetailsViewController: UIViewController, UITextFieldDelegate, UIPickerViewDelegate, UIPickerViewDataSource {
    let realm = try! Realm()

    //Create Picker Views

    let dateAppointedPickerView = UIDatePicker()

    @IBOutlet weak var clientDateAppointedText: UITextField!


    var selectedClient : Client? {
        //Everything in the did set function will happen as soon as this variable is set with a value
        didSet {
            loadClientDetails()
        }
    }

    override func viewDidLoad() {
        super.viewDidLoad()

        //Assign Picker Views
        setPickerViews()

        //Assign Picker View Settings
        setPickerViewSettings()

        //Assign Picker View Delegates
        setDelegates()
    }

    //MARK: - Date Format Method

    func formatDateToString(_ date: Date) -> String {

        let dateFormatter = DateFormatter()
        dateFormatter.dateFormat = "MMMM dd, yyyy"
        dateFormatter.locale = Locale.current
        let formattedDate = dateFormatter.string(from: date)

        return formattedDate
    }

    func formatStringToDate(_ dateString: String) -> Date {

        let dateFormatter = DateFormatter()
        dateFormatter.dateFormat = "MMMM dd, yyyy"
        dateFormatter.locale = Locale.current
        let formattedDate = dateFormatter.date(from: dateString)

        return formattedDate!
    }

    func loadClientDetails() {
        loadViewIfNeeded()

        clientDateAppointedText.text = formatDateToString((selectedClient?.dateAppointed)!)

    }

    //Send textfield/picker data to database
    func textFieldDidEndEditing(_ textField: UITextField) {
        var clientData : String = ""

        guard let currentClient = selectedClient else {fatalError()}
        switch textField {

        case clientDateAppointedText:
            clientData = "clientDateAppointedText"
            updateClientDetails(currentClient, clientData)
        default:
            print("Did not edit anything")
        }
    }

    //MARK: - Data Manipulation Methods

    func updateClientDetails(_ clientInfo: Client,_ clientString: String) {

        let editClient : String = clientString
        do {
            try realm.write {
                switch editClient {

                case "clientDateAppointedText":
                    clientInfo.dateAppointed = formatStringToDate(clientDateAppointedText.text!)
                default:
                    print("Unable to edit client information")
                }
            }
        } catch {
            print("Unable to save client details")
        }
    }

我希望日期选择器在每次选择新日期时更新文本视图，并将值传递给要更新的数据库。实际结果是传递的值一遍又一遍是同一个日期。

标签： iosswiftdatepickeruidatepicker

Answer 1

步骤：

1. 首先初始化pickerview

    var datePickerView:UIDatePicker = UIDatePicker()
   

2. 通过情节提要创建文本字段的动作，即“编辑开始”

   @IBAction func textEditing(_ sender: UITextField)
   {
      isPickUpSelected = true
      datePickerView = UIDatePicker()
      datePickerView.minimumDate = Date()
      datePickerView.date = selectedPickupDate
      datePickerView.datePickerMode = UIDatePickerMode.date
      sender.inputView = datePickerView
      datePickerView.addTarget(self, action: 
      #selector(TUGBestDealVC.datePickerValueChanged), for: 
      UIControlEvents.valueChanged)
      self.addToolBar(picker: datePickerView, textField: sender)
   }
   

3. 编写 addToolbar 函数来自定义 datepicker：

   func addToolBar(picker: UIDatePicker, textField: UITextField) 
   {
      toolBar.barStyle = .default
      toolBar.isTranslucent = true
      toolBar.tintColor = UIColor.darkGray
      toolBar.sizeToFit()
      let doneButton = UIBarButtonItem(title: TUGHelpers().getLocalisedString(strKey: 
      "DONE"),style: .plain, target: self, 
      action:#selector(TUGBestDealVC.doneClick(sender:)))
      doneButton.tag = picker.tag
      let spaceButton = UIBarButtonItem(barButtonSystemItem: .flexibleSpace, target: 
      nil,action: nil)
      let cancelButton = UIBarButtonItem(title:"Cancel", style: .plain, target: self, 
      action:#selector(TUGBestDealVC.cancelClick(sender:)))
      cancelButton.tag = picker.tag+4
      toolBar.setItems([cancelButton, spaceButton, doneButton], animated: false)
      toolBar.isUserInteractionEnabled = true
      textField.inputAccessoryView = toolBar
   }
   

4. 跟踪日期选择器更改日期的操作：

   func datePickerValueChanged(sender:UIDatePicker)
   {
       self.setPickupDate(date: sender.date)     
   }
   

5. 这是 datepickerview 的完成操作：

   @objc func doneClick(sender: UIButton)
   {
       self.setPickupDate(date: datePickerView.date)
       dateTxt.resignFirstResponder()
   }
   

6. 这是 datepickerview 的取消操作：

   @objc func cancelClick(sender: UIButton) 
   {
        dateTxt.resignFirstResponder()
   }
   

7. 在这里你会得到pickerview的日期：

   func setPickupDate(date: Date)
   {
       print(date)
   }
   

每次都可以在数据库中更新相同的代码

享受，快乐编码。