我希望用户能够单击表中的单元格，并且它检索该索引路径处的任何对象并将其设置为变量，以便我可以将其拉到下一个VC。
如何实现的？我的逻辑是使用类似：
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "loadTodaysRoutine" {
setRoutine = fetchedResultsController.fetchedobjects[indexPath.row]
if let todaysRoutineController = segue.destination as? RoutineController {
todaysRoutineController.routineObject = setRoutine
}
我认为这会使setRoutine索引补丁被单击，然后我可以通过segue将其发送到另一个VC，但是我感觉我缺少一些步骤，因为它不起作用！
多谢您的协助，以填补我的理解空白
更新，根据要求提供整个VC
import Foundation
import UIKit
import CoreData
class YourWorkoutsController: UIViewController, UITableViewDataSource, UITableViewDelegate, NSFetchedResultsControllerDelegate {
// MARK: - DECLARATIONS
private let persistentContainer = NSPersistentContainer(name: "Lift")
var managedObjectContext: NSManagedObjectContext?
fileprivate var setRoutine: NSManagedObject?
@IBAction func unwindToTemplates(segue: UIStoryboardSegue) {}
@IBOutlet weak var workoutTemplateTable: UITableView!
@IBOutlet weak var createWorkoutLabel: UILabel!
@IBOutlet weak var nameLabel: UILabel!
// MARK: - ACTIONS
@IBAction func cancelWorkoutSelection(_ sender: Any) {
self.performSegue(withIdentifier: "unwindToRoutineWithSegue", sender: self)
}
// MARK: - VIEWDIDLOAD
override func viewDidLoad() {
super.viewDidLoad()
setupView()
workoutTemplateTable.delegate = self
workoutTemplateTable.dataSource = self
view.backgroundColor = (UIColor.customBackgroundGraphite())
persistentContainer.loadPersistentStores { (persistentStoreDescription, error) in
if let error = error {
print("Unable to Load Persistent Store")
print("\(error), \(error.localizedDescription)")
} else {
self.setupView()
do {
try self.fetchedResultsController.performFetch()
} catch {
let fetchError = error as NSError
print("Unable to Perform Fetch Request")
print("\(fetchError), \(fetchError.localizedDescription)")
}
self.updateView()
}
}
}
// MARK: - VIEWWILLAPPEAR
override func viewWillAppear(_ animated: Bool) {
do {
try self.fetchedResultsController.performFetch()
} catch {
let fetchError = error as NSError
print("Unable to Perform Fetch Request")
print("\(fetchError), \(fetchError.localizedDescription)")
}
self.workoutTemplateTable.reloadData()
}
// MARK: - TABLE SETUP
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
guard let userRoutine = fetchedResultsController.fetchedObjects else { return 0 }
return userRoutine.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)
cell.backgroundColor = UIColor.customBackgroundGraphite()
cell.textLabel?.textColor = UIColor.white
let userRoutine = fetchedResultsController.object(at: indexPath)
cell.textLabel?.text = userRoutine.name
return cell
}
// MARK: - TABLE UPDATING COMPONENTS
private func setupView() {
setupMessageLabel()
updateView()
}
private func setupMessageLabel() {
createWorkoutLabel.text = "You Don't Have Any Workouts Yet\n Tap + To Create A New Workout"
}
fileprivate func updateView() {
var hasUserRoutines = false
if let UserRoutine = fetchedResultsController.fetchedObjects {
hasUserRoutines = UserRoutine.count > 0
}
workoutTemplateTable.isHidden = !hasUserRoutines
createWorkoutLabel.isHidden = hasUserRoutines
}
// MARK: - COREDATA FETCH
fileprivate lazy var fetchedResultsController: NSFetchedResultsController<UserRoutine> = {
// Create Fetch Request
let fetchRequest: NSFetchRequest<UserRoutine> = UserRoutine.fetchRequest()
// Configure Fetch Request
fetchRequest.sortDescriptors = [NSSortDescriptor(key: "name", ascending: true)]
// Create Fetched Results Controller
let fetchedResultsController = NSFetchedResultsController(fetchRequest: fetchRequest, managedObjectContext: self.persistentContainer.viewContext, sectionNameKeyPath: nil, cacheName: nil)
// Configure Fetched Results Controller
fetchedResultsController.delegate = self
return fetchedResultsController
}()
// MARK: - ADDING NEW ROUTINE TO THE VC / PUSHING ROUTINE TO TODAYSROUTINE VC
override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
self.setRoutine = fetchedResultsController.fetchedObjects[indexPath.row]
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "addNewRoutineSegue" {
if let destinationViewController = segue.destination as? WorkoutDesignerController {
// Configure View Controller
destinationViewController.managedObjectContext = persistentContainer.viewContext
}
}
if segue.identifier == "loadTodaysRoutine" {
if let todaysRoutineController = segue.destination as? RoutineController {
todaysRoutineController.routineObject = self.setRoutine
}
}
}
func controllerWillChangeContent(_ controller: NSFetchedResultsController<NSFetchRequestResult>) {
workoutTemplateTable.beginUpdates()
}
func controllerDidChangeContent(_ controller: NSFetchedResultsController<NSFetchRequestResult>) {
workoutTemplateTable.endUpdates()
updateView()
}
// MARK: - ADDING TABLE ROW
func controller(_ controller: NSFetchedResultsController<NSFetchRequestResult>, didChange anObject: Any, at indexPath: IndexPath?, for type: NSFetchedResultsChangeType, newIndexPath: IndexPath?) {
switch (type) {
case .insert:
if let indexPath = newIndexPath {
workoutTemplateTable.insertRows(at: [indexPath], with: .fade)
}
break;
case .delete:
if let indexPath = indexPath {
workoutTemplateTable.deleteRows(at: [indexPath], with: .fade)
}
break;
default:
print("...")
}
}
// MARK: - DELETING TABLE ROW
func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCellEditingStyle, forRowAt indexPath: IndexPath) {
if editingStyle == .delete {
//fetch exercise
let UserRoutine = fetchedResultsController.managedObjectContext
//delete exercise
UserRoutine.delete(fetchedResultsController.object(at: indexPath))
//save exercise persistence
do {
try UserRoutine.save()
} catch {
let nserror = error as NSError
fatalError("Unresolved error \(nserror), \(nserror.userInfo)")
}
}
}
}
最佳答案
首先在当前的var中创建一个本地VC，然后在didSelectRow中为其分配值，如下所示：
fileprivate var setRoutine: Any?
.....
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
if let routine = fetchedResultsController.fetchedObjects[indexPath.row] {
self.setRoutine = routine
}
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "loadTodaysRoutine" {
if let todaysRoutineController = segue.destination as? RoutineController {
todaysRoutineController.routineObject = self.setRoutine
}
}
}
关于swift - 使用fetchcontroller从Tableview单元中获取对象？，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/41062342/