Я отображаю все свои записи в виде таблицы, и когда пользователь нажимает на запись, пользователь перемещается на страницу редактирования, где он может редактировать запись и удалять запись.Как я на самом деле реализую эту функцию?Прямо сейчас я переместил пользователя на страницу редактирования только после того, как он щелкнул по записи для редактирования.
Просмотр контроллера с табличным представлением для отображения записей.
import UIKit
class ViewController8: UIViewController, UITableViewDelegate, UITableViewDataSource {
let appDelegate = UIApplication.shared.delegate as! AppDelegate
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return appDelegate.getFriendRecord().count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell: UITableViewCell = tableView.dequeueReusableCell (withIdentifier: "myCell", for: indexPath)
cell.textLabel!.text = appDelegate.getFriendRecord()[indexPath.row]
return cell;
}
@IBOutlet weak var tableView: UITableView!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
Просмотр контроллера для редактирования страницы
import UIKit
class ViewController3: UIViewController {
let appDelegate = UIApplication.shared.delegate as! AppDelegate
var genderStr: String = ""
@IBOutlet weak var ageStepper: UIStepper!
@IBOutlet weak var firstName: UITextField!
@IBOutlet weak var lastName: UITextField!
@IBOutlet weak var address: UITextField!
@IBOutlet weak var segControl: UISegmentedControl!
@IBOutlet weak var ageLabel: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
@IBAction func stepperAction(_ sender: Any) {
let step = Int(ageStepper.value)
ageLabel.text = String(step)
}
@IBAction func deleteAction(_ sender: Any) {
}
@IBAction func submitAction(_ sender: Any) {
if segControl.selectedSegmentIndex == 0 {
genderStr = "Male"
}
else {
genderStr = "Female"
}
}
Файл AppDelegate
import UIKit
import CoreData
@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
var window: UIWindow?
func getContext () -> NSManagedObjectContext {
let appDelegate = UIApplication.shared.delegate
as! AppDelegate
return appDelegate.persistentContainer.viewContext
}
func storeFriendRecord (firstName: String, lastName: String, gender: String, age: String, address: String)
{
let context = persistentContainer.viewContext
let entity = NSEntityDescription.entity(forEntityName: "Friend", in : context)
let transc = NSManagedObject(entity: entity!, insertInto: context)
transc.setValue(firstName, forKey: "firstName")
transc.setValue(lastName, forKey: "lastName")
transc.setValue(gender, forKey: "gender")
transc.setValue(age, forKey: "age")
transc.setValue(address, forKey: "address")
do {
try context.save()
} catch let error as NSError {
print("Could not save \(error), \(error.userInfo)")
} catch {}
}
func getFriendRecord () -> [String] {
var info: [String] = []
let fetchRequest: NSFetchRequest<Friend> = Friend.fetchRequest()
do {
let searchResults = try getContext().fetch(fetchRequest)
for trans in searchResults as [NSManagedObject] {
let firstName = String(trans.value(forKey: "firstName") as! String)
let lastName = String(trans.value(forKey: "lastName") as! String)
let gender = String(trans.value(forKey: "gender") as! String)
let age = String(trans.value(forKey: "age") as! String)
let address = String(trans.value(forKey: "address") as! String)
//info = info + firstName + ", " + lastName + ", " + gender + ", " + age + ", " + address + "\n"
let record = [firstName, lastName, gender, age, address].joined(separator: ", ") + "\n"
info.append(record)
}
} catch {
print("Error with request: \(error)")
}
return info;
}
func removeRecords () {
let context = getContext()
let deleteFetch = NSFetchRequest<NSFetchRequestResult>(entityName: "Friend")
let deleteRequest = NSBatchDeleteRequest(fetchRequest: deleteFetch)
do {
try context.execute(deleteRequest)
try context.save()
} catch {
print ("There was an error")
}
}
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:.
// Saves changes in the application's managed object context before the application terminates.
self.saveContext()
}
// 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: "PersonalManagementApp")
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)")
}
}
}
}
Обратите внимание, что этот вопрос отличается от предыдущего вопроса, который я задавал.Этот вопрос спрашивает, как удалить запись, предыдущий вопрос был о том, как редактировать запись.