iOS 12错误：似乎来自与该上下文不同的NSManagedObjectModel [英] iOS 12 Errors: appears to be from a different NSManagedObjectModel than this context's
问题描述
在iOS 12模拟器上启动我的应用程序时，我开始出现以下错误。有人遇到过这样的问题吗？
I started to get the following error when launching my application on iOS 12 simulator. Did anybody face issue like this?
2018-08-11 21:17:44.440144+0300 CafeManager[4633:128874] [error] error: The fetch request's entity 0x600001f6e940 'TablesTable' appears to be from a different NSManagedObjectModel than this context's
I have global constant defined in AppDelegate:
let viewContext = AppDelegate.viewContext
并与NSFetchedResultsController一起用于UITableView更新，例如：
And use it with NSFetchedResultsController for UITableView update, for example:
import UIKit
import CoreData
class HistoryTablesTableViewController: FetchedResultsTableViewController {
//MARK: variables
private var fetchedResultsController: NSFetchedResultsController<TablesTable>?
private var currentTable: TablesTable?
private var tableNameTextField: UITextField!
//MARK: system functions for view
override func viewDidLoad() {
super.viewDidLoad()
sideMenu()
addSyncObserver()
}
override func viewWillAppear(_ animated: Bool) {
updateGUI()
}
// MARK: IBOutlets
@IBOutlet weak var menuButton: UIBarButtonItem!
// MARK: side menu
private func sideMenu() {
if revealViewController() != nil {
menuButton.target = revealViewController()
menuButton.action = #selector(SWRevealViewController.revealToggle(_:))
revealViewController().rearViewRevealWidth = 260
view.addGestureRecognizer(self.revealViewController().panGestureRecognizer())
}
}
//MARK: functions for table update
private func updateGUI () {
let request : NSFetchRequest<TablesTable> = TablesTable.fetchRequest()
request.sortDescriptors = [NSSortDescriptor(key: "tableName", ascending: true, selector: #selector(NSString.localizedStandardCompare(_:)))]
fetchedResultsController = NSFetchedResultsController<TablesTable>(fetchRequest: request, managedObjectContext: viewContext, sectionNameKeyPath: nil, cacheName: nil)
try? fetchedResultsController?.performFetch()
tableView.reloadData()
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "tableCell", for: indexPath) as! HistoryTablesTableViewCell
if let tablesTable = fetchedResultsController?.object(at: indexPath) {
cell.tableNameLabel.text = tablesTable.tableName
cell.cellDelegate = self
cell.table = tablesTable
}
return cell
}
override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
let cell = tableView.cellForRow(at: indexPath as IndexPath)
tableView.deselectRow(at: indexPath as IndexPath, animated: true)
currentTable = fetchedResultsController?.object(at: indexPath)
performSegue(withIdentifier: "showTableSessions", sender: cell)
}
//MARK: prepare for segue
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "showTableSessions" {
if let tableSessionsTVC = segue.destination as? TableSessionsTableViewController {
tableSessionsTVC.title = self.currentTable!.tableName!
tableSessionsTVC.currentTable = self.currentTable!
}
}
}
}
// MARK: Delegates
extension HistoryTablesTableViewController: HistoryTablesTableViewCellDelegate {
func didPressTablesCellButton(table: TablesTable) {
currentTable = table
}
}
// Common extension for fetchedResultsController
extension HistoryTablesTableViewController {
override func numberOfSections(in tableView: UITableView) -> Int {
return fetchedResultsController?.sections?.count ?? 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
if let sections = fetchedResultsController?.sections, sections.count > 0 {
return sections[section].numberOfObjects
}
else {
return 0
}
}
override func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
if let sections = fetchedResultsController?.sections, sections.count > 0 {
return sections[section].name
}
else {
return nil
}
}
override func sectionIndexTitles(for tableView: UITableView) -> [String]? {
return fetchedResultsController?.sectionIndexTitles
}
override func tableView(_ tableView: UITableView, sectionForSectionIndexTitle title: String, at index: Int) -> Int {
return fetchedResultsController?.section(forSectionIndexTitle: title, at: index) ?? 0
}
}
// Observer to check that sync was performed to update GUI
extension HistoryTablesTableViewController {
private func addSyncObserver () {
NotificationCenter.default.addObserver(forName: Notification.Name(rawValue: appDelegate.syncDidFinishNotification), object: nil, queue: nil) {
[weak self] notification in
DispatchQueue.main.async {
self?.updateGUI()
}
}
}
}
同时看起来该应用程序可以运行，但是还没有机会正确测试所有内容。
In the same time it looks like that app works, but had no chance to test everything properly yet.
我使用CoreData，Seam3框架。
I use CoreData, Seam3 framework.
我在 github ，但看不到解决方案。
I found the only one mention of this error on github, but do not see solution.
推荐答案
我在iOS上遇到此错误12也。这就是我最终在项目中修复它的方式。这是在目标C中，而不是Swift中，但希望它将使您朝正确的方向前进。
I had been getting this error with iOS 12 also. This is how I finally fixed it in my project. This is in Objective C, not Swift, but hopefully it will get you going in the right direction.
产生此错误的代码如下所示：
The code that produced this error looked like this
// in the init code for my object
NSString *pathm = [[NSBundle mainBundle] pathForResource:@"mycoredb" ofType:@"momd"];
NSURL *momURL = [NSURL fileURLWithPath:pathm];
self.model = [[NSManagedObjectModel alloc] initWithContentsOfURL:momURL];
// in another method in the object
NSFetchRequest *request = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [[self.model entitiesByName] objectForKey:@"Model_name"];
[request setEntity:entity];
问题与实体有关。因此，我更新了代码以反映此页面上的示例： https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/CoreData/FetchingObjects.html
The issue has something to do with the entity. So I updated my code to reflect the example on this page: https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/CoreData/FetchingObjects.html
这是我的代码现在看
NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"Model_name"];
没有更多似乎是来自与上下文不同的NSManagedObjectModel错误。
no more "appears to be from a different NSManagedObjectModel than this context" error.
这篇关于iOS 12错误：似乎来自与该上下文不同的NSManagedObjectModel的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
