Question

当用户单击导航栏中的+按钮时，会出现带有文本提示的UIAlert。然后，用户在提示符中输入一个字符串，它应该生成一个名为字符串的新UITableViewCell。

出于某种原因，当我到达此viewController的屏幕时，应用程序崩溃了。

它认为它与ViewDidLoad中的以下行相关：NSEntityDescription *entity = [NSEntityDescription entityForName:@"Routine" inManagedObjectContext:managedObjectContext];。

控制台说明以下内容：Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: '+entityForName: could not locate an NSManagedObjectModel for entity name 'Routine''

我认为我需要使用“名称”而不是常规，但这也不起作用。

以下是我的核心数据模型： enter image description here

这是我的代码：

#import "RoutineTableViewController.h"
#import "AlertPrompt.h"
#import "Routine.h"

@implementation RoutineTableViewController

@synthesize tableView;
@synthesize eventsArray;
@synthesize managedObjectContext;

    - (void)dealloc
    {
        [managedObjectContext release];
        [eventsArray release];
        [super dealloc];
    }

    - (void)didReceiveMemoryWarning
    {
        [super didReceiveMemoryWarning];
    }

    #pragma mark - View lifecycle

    - (void)viewDidLoad
    {
        UIBarButtonItem * addButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:@selector(showPrompt)];
        [self.navigationItem setLeftBarButtonItem:addButton];
        [addButton release];

        UIBarButtonItem *editButton = [[UIBarButtonItem alloc]initWithTitle:@"Edit" style:UIBarButtonItemStyleBordered target:self action:@selector(toggleEdit)];
        self.navigationItem.rightBarButtonItem = editButton;
        [editButton release];

        NSFetchRequest *request = [[NSFetchRequest alloc] init];
        NSEntityDescription *entity = [NSEntityDescription entityForName:@"Routine" inManagedObjectContext:managedObjectContext];
        [request setEntity:entity];

        NSError *error = nil;
        NSMutableArray *mutableFetchResults = [[managedObjectContext executeFetchRequest:request error:&error] mutableCopy];
        if (mutableFetchResults == nil) {
            // Handle the error.
        }

        [self setEventsArray:mutableFetchResults];
        [mutableFetchResults release];
        [request release];

        [super viewDidLoad];
    }

    -(void)toggleEdit
    {
        [self.tableView setEditing: !self.tableView.editing animated:YES];

        if (self.tableView.editing)
            [self.navigationItem.rightBarButtonItem setTitle:@"Done"];
        else
            [self.navigationItem.rightBarButtonItem setTitle:@"Edit"];
    }

    -(void)showPrompt
    {
        AlertPrompt *prompt = [AlertPrompt alloc];
        prompt = [prompt initWithTitle:@"Add Workout Day" message:@"\n \n Please enter title for workout day" delegate:self cancelButtonTitle:@"Cancel" okButtonTitle:@"Add"];

        [prompt show];
        [prompt release];
    }

    - (void)alertView:(UIAlertView *)alertView willDismissWithButtonIndex:(NSInteger)buttonIndex
    {
        if (buttonIndex != [alertView cancelButtonIndex])
        {
            NSString *entered = [(AlertPrompt *)alertView enteredText];
            if(eventsArray && entered)
            {
                [eventsArray addObject:entered];
                [tableView reloadData];
            }
        }
    }

    -(void)addEvent
    {
        Routine *routine = (Routine *)[NSEntityDescription insertNewObjectForEntityForName:@"Routine" inManagedObjectContext:managedObjectContext];

        NSError *error = nil;
        if (![managedObjectContext save:&error]) {
            // Handle the error.
        }

        [eventsArray insertObject:routine atIndex:0];
        NSIndexPath *indexPath = [NSIndexPath indexPathForRow:0 inSection:0];
        [self.tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:indexPath]
                              withRowAnimation:UITableViewRowAnimationFade];
        [self.tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:0 inSection:0] atScrollPosition:UITableViewScrollPositionTop animated:YES];
    }

    - (void)viewDidUnload
    {
        self.eventsArray = nil;
        [super viewDidUnload];
    }

#pragma mark - Table view data source

    - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
    {
        return 1;
    }

    - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
    {
        return [eventsArray count];
    }

    - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
    {
        static NSString *CellIdentifier = @"Cell";

        UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
        if (cell == nil) {
            //cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
            cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellEditingStyleDelete reuseIdentifier:CellIdentifier] autorelease];
        }
        cell.textLabel.text = [self.eventsArray objectAtIndex:indexPath.row];

        return cell;
    }
    // Override to support conditional editing of the table view.
    - (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath
    {
        // Return NO if you do not want the specified item to be editable.
        return YES;
    }

    -(void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
     {

         if (editingStyle == UITableViewCellEditingStyleDelete) {

             // Delete the managed object at the given index path.
             NSManagedObject *eventToDelete = [eventsArray objectAtIndex:indexPath.row];
             [managedObjectContext deleteObject:eventToDelete];

             // Update the array and table view.
             [eventsArray removeObjectAtIndex:indexPath.row];
             [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:YES];

             // Commit the change.
             NSError *error = nil;
             if (![managedObjectContext save:&error]) {
                 // Handle the error.
             }
         }
     }    
    @end

Answer 1

我没有看到您的ManagedObjectContext被声明并挂钩到现有数据模型中的位置。就像在哪里，你在哪里声明你的“getter”从 persistentStoreCoordinator 访问它。尝试检查您的连接并插入viewDidLoad。并查看此处的文档步骤：

http://developer.apple.com/library/mac/#documentation/Cocoa/Conceptual/CoreData/Articles/cdUsingMOM.html#//apple_ref/doc/uid/TP40005190-SW1

这是一个挂钩你的perstistantStoreCoordinator

的例子

- (NSManagedObjectContext *) managedObjectContext {

if (managedObjectContext != nil) {
    return managedObjectContext;
}

NSPersistentStoreCoordinator *coordinator = [self persistentStoreCoordinator];
if (coordinator != nil) {
    managedObjectContext = [[NSManagedObjectContext alloc] init];
    [managedObjectContext setPersistentStoreCoordinator: coordinator];
}
return managedObjectContext;

}

或者从您正在使用的教程中，您将在应用程序委托的 didFinishLaunching 方法中看到它：

NSManagedObjectContext *context = [self managedObjectContext];
if (!context) {
    // Handle the error.
}
// Pass the managed object context to the view controller.
rootViewController.managedObjectContext = context;

修改

审核完代码后，您需要做两件事：

1）编辑AppDelegate以加载“Curl”模型，而不是“Temp”模型。这是你的xdatamodel的名字。

2）你需要引用你的app delegate的上下文而不是在本地创建一个。即。

CurlAppDelegate *curlAppDelegate = [[UIApplication sharedApplication] delegate]; NSManagedObjectContext *context = [curlAppDelegate managedObjectContext]; NSFetchRequest *request = [[NSFetchRequest alloc] init]; NSEntityDescription *entity = [NSEntityDescription entityForName:@"Routine" inManagedObjectContext:context]; [request setEntity:entity]; NSError *error = nil; NSMutableArray *mutableFetchResults = [[context executeFetchRequest:request error:&error] mutableCopy]; if (mutableFetchResults == nil) { // Handle the error. }

Answer 2

“NSInternalInconsistencyException”错误与将基础数据模型更改为Core Data无法执行automatic lightweight data migration的程度相关：现在用于存储数据的实际SQLite或plist文件与数据模型的新结构不兼容。

要清除它，您可以通过常规方式从模拟器（或设备，如果您正在测试的地方）删除应用程序 - 按住应用程序图标直到它摆动然后点击/单击X - 或者从Mac上应用程序的工作目录中删除文件本身。

~/Library/Application Support/iPhone Simulator/YOUR-IOS-BASE-SDK-HERE/Applications/YOUR-36-BYTE-APP-ID-HERE/Documents

（或者如果不是文件，无论你使用哪个文件夹。）

之后，您可以运行应用程序，此特定错误将消失，因为Core Data将能够再次从头开始创建文件。

由于核心数据错误导致TableView崩溃/冻结

2 个答案: