Я создаю простое приложение, в котором я могу добавить еду (еду) в список, а затем забрать эти блюда с помощью UIPicker из другого V C. Это прекрасно работает, но я не могу сохранить это. (данные не сохраняются после перезапуска). Я пытаюсь сделать это с coreData, и я вижу в списке кодов, что события / изменения на самом деле сохраняются и загружаются. (Я успешно использовал coreData в других приложениях)
Кто-нибудь может мне помочь? Что мне делать? Я довольно новичок в IOS dev и Swift, поэтому, пожалуйста, будьте ясны и уточните c =)
Вот мой код:
Пожалуйста, скажите мне, если вам нужно что-нибудь еще, чтобы помочь мне , Большое спасибо StackOverflow!
V C 1:
import UIKit
import CoreData
var List = ["Pasta Pesto", "Spenat Soppa", "Ris, Quorn & Currysås", "Lins Soppa"]
class ViewController: UIViewController {
@IBOutlet weak var monday: UITextField!
@IBOutlet weak var tuesday: UITextField!
@IBOutlet weak var wednesday: UITextField!
@IBOutlet weak var thursday: UITextField!
@IBOutlet weak var friday: UITextField!
@IBOutlet weak var saturday: UITextField!
@IBOutlet weak var sunday: UITextField!
var daysArray = [UITextField]()
let pickerView = ToolbarPickerView()
var selectedMenu : String?
override func viewDidLoad() {
super.viewDidLoad()
setupDelegateForPickerView()
setupDelegatesForTextFields()
coredataClass.loadData()
}
func setupDelegatesForTextFields() {
//appending textfields in an array
daysArray += [monday, tuesday, wednesday, thursday, friday, saturday, sunday]
//using the array to set up the delegates, inputview for pickerview and also the inputAccessoryView for the toolbar
for day in daysArray {
day.delegate = self
day.inputView = pickerView
day.inputAccessoryView = pickerView.toolbar
}
}
func setupDelegateForPickerView() {
pickerView.dataSource = self
pickerView.delegate = self
pickerView.toolbarDelegate = self
}
}
// Create an extension for textfield delegate
extension ViewController : UITextFieldDelegate {
func textFieldDidBeginEditing(_ textField: UITextField) {
self.pickerView.reloadAllComponents()
}
}
// Extension for pickerview and toolbar
extension ViewController : UIPickerViewDelegate, UIPickerViewDataSource {
func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
return List.count
}
func numberOfComponents(in pickerView: UIPickerView) -> Int {
return 1
}
func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
return List[row]
}
func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
// Check if the textfield isFirstResponder.
if monday.isFirstResponder {
monday.text = List[row]
} else if tuesday.isFirstResponder {
tuesday.text = List[row]
} else if wednesday.isFirstResponder {
wednesday.text = List[row]
} else if thursday.isFirstResponder {
thursday.text = List[row]
} else if friday.isFirstResponder {
friday.text = List[row]
} else if saturday.isFirstResponder {
saturday.text = List[row]
} else if sunday.isFirstResponder {
sunday.text = List[row]
} else {
//log errors
}
}
// PickerView's didSelectRow function can be simplified by changing it to below
// func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
//
// for day in daysArray {
// if day.isFirstResponder {
// day.text = self.Menu[row]
// }
// }
// }
}
extension ViewController: ToolbarPickerViewDelegate {
func didTapDone() {
// let row = self.pickerView.selectedRow(inComponent: 0)
// self.pickerView.selectRow(row, inComponent: 0, animated: false)
// selectedMenu = self.Menu[row]
self.view.endEditing(true)
}
func didTapCancel() {
self.view.endEditing(true)
}
}
V C 2:
import UIKit
import CoreData
class addViewController: UIViewController, UITextFieldDelegate {
@IBOutlet weak var input: UITextField!
@IBAction func addToMenu(_ sender: Any) {
if (input.text != "")
{
List.append(input.text!)
input.text = ""
}
input.delegate = self
coredataClass.saveItems()
}
override func viewDidLoad() {
super.viewDidLoad()
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
self.view.endEditing(true)
}
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
input.resignFirstResponder()
return true
}
}
V C 3:
import UIKit
import CoreData
class tableViewController: UIViewController, UITableViewDelegate, UITableViewDataSource{
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return (List.count)
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = UITableViewCell(style: .default, reuseIdentifier: "cell")
cell.textLabel?.text = List[indexPath.row]
cell.textLabel?.textColor = UIColor.white
cell.backgroundColor = UIColor.clear
return(cell)
}
func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCell.EditingStyle, forRowAt indexPath: IndexPath) {
if editingStyle == UITableViewCell.EditingStyle.delete
{
List.remove(at: indexPath.row)
myTableView.reloadData()
}
}
@IBOutlet weak var myTableView: UITableView!
override func viewDidAppear(_ animated: Bool) {
myTableView.reloadData()
}
override func viewDidLoad() {
super.viewDidLoad()
coredataClass.saveItems()
coredataClass.loadData()
}
}
AppDelegate:
import UIKit
import CoreData
@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
var window: UIWindow?
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
// Override point for customization after application launch.
return true
}
func applicationWillResignActive(_ application: UIApplication) {
// Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
// Use this method to pause ongoing tasks, disable timers, and invalidate graphics rendering callbacks. Games should use this method to pause the game.
}
func applicationDidEnterBackground(_ application: UIApplication) {
// Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
// If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
}
func applicationWillEnterForeground(_ application: UIApplication) {
// Called as part of the transition from the background to the active state; here you can undo many of the changes made on entering the background.
}
func applicationDidBecomeActive(_ application: UIApplication) {
// Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
}
func applicationWillTerminate(_ application: UIApplication) {
// Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
}
// MARK: - Core Data stack
lazy var persistentContainer: NSPersistentContainer = {
/*
The persistent container for the application. This implementation
creates and returns a container, having loaded the store for the
application to it. This property is optional since there are legitimate
error conditions that could cause the creation of the store to fail.
*/
let container = NSPersistentContainer(name: "bonAPPetit")
container.loadPersistentStores(completionHandler: { (storeDescription, error) in
if let error = error as NSError? {
// Replace this implementation with code to handle the error appropriately.
// fatalError() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
/*
Typical reasons for an error here include:
* The parent directory does not exist, cannot be created, or disallows writing.
* The persistent store is not accessible, due to permissions or data protection when the device is locked.
* The device is out of space.
* The store could not be migrated to the current model version.
Check the error message to determine what the actual problem was.
*/
fatalError("Unresolved error \(error), \(error.userInfo)")
}
})
return container
}()
// MARK: - Core Data Saving support
func saveContext () {
let context = persistentContainer.viewContext
if context.hasChanges {
do {
try context.save()
} catch {
// Replace this implementation with code to handle the error appropriately.
// fatalError() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
let nserror = error as NSError
fatalError("Unresolved error \(nserror), \(nserror.userInfo)")
}
}
}
}
coredataClass:
import UIKit
import CoreData
class coredataClass {
static var items = [MealsMenu]()
static let context = (UIApplication.shared.delegate as! AppDelegate).persistentContainer.viewContext
static func saveItems(){
do{
try coredataClass.context.save()
print("SAVED")
}catch{
print("Error saving context with")
}
}
static func loadData(){
let request: NSFetchRequest<MealsMenu> = MealsMenu.fetchRequest()
do{
items = try coredataClass.context.fetch(request)
print("LOADED")
}catch{
print("Error fetching data from context")
}
}
}