此 NSZombie 错误消息是什么意思？

Question

我打开僵尸是因为我遇到了一些崩溃。现在我在控制台中收到此错误。有谁知道这意味着什么？

*** -[RoutineDayTableViewController keep]: 消息发送到已释放实例 0x7464150

@implementation RoutineDayTableViewController

@synthesize fetchedResultsController;
@synthesize exerciseChooserView;
@synthesize routineTableView;
@synthesize managedObjectContext;
@synthesize selectedExercise;
@synthesize theSelectedRoutine;

- (void)dealloc
{
    NSLog(@"dealloc");
    [fetchedResultsController release];
    [selectedExercise release];
    [managedObjectContext release];
    [exerciseChooserView release];
    [routineTableView release];
    [theSelectedRoutine release];
    [super dealloc];
}

- (void)didReceiveMemoryWarning
{
    // Releases the view if it doesn't have a superview.
    [super didReceiveMemoryWarning];
}

#pragma mark - View lifecycle

- (void)viewDidLoad
{
    [super viewDidLoad];

    self.routineTableView.delegate = self;
    if (managedObjectContext == nil) 
    { 
        managedObjectContext = [(CurlAppDelegate *)[[UIApplication sharedApplication] delegate] managedObjectContext]; 
        [managedObjectContext retain];
    }
}

- (void)viewDidUnload
{
    NSLog(@"viewDidUnload");
    [super viewDidUnload];
    self.exerciseChooserView = nil;
    self.routineTableView = nil;
    self.fetchedResultsController = nil;
}

#pragma mark - Exercise Editing

-(IBAction)exerciseChooser
{
    RoutineExerciseChooserViewController *routineExerciseChooserViewController = [[[RoutineExerciseChooserViewController alloc] init] autorelease];
    [self.navigationController pushViewController:routineExerciseChooserViewController animated:YES];
}

-(void)addExercise
{   
    if (managedObjectContext == nil) 
    { 
        managedObjectContext = [(CurlAppDelegate *)[[UIApplication sharedApplication] delegate] managedObjectContext]; 
        [managedObjectContext retain];
    }

    UIBarButtonItem *addButton = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:@selector(exerciseChooser)];
    self.navigationItem.rightBarButtonItem = addButton;
    [addButton release];

    NSError *error = nil;

    Exercise *exercise = (Exercise *)[NSEntityDescription insertNewObjectForEntityForName:@"Exercise" inManagedObjectContext:managedObjectContext];

    exercise.name = self.selectedExercise;

    NSLog(@"addExercise theSelectedRoutine:  %@", theSelectedRoutine);

    [self.theSelectedRoutine addRoutineToExercisesObject:exercise];

    if (![fetchedResultsController.managedObjectContext save:&error]) 
    {
        // Handle the error.
    }
    NSLog(@"%@", error);
    NSLog(@"addExercise theSelectedRoutine:  %@", theSelectedRoutine);
}



#pragma mark - Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    return [[self.fetchedResultsController sections] count];
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    id <NSFetchedResultsSectionInfo> sectionInfo = [[self.fetchedResultsController sections] objectAtIndex:section];
    return [sectionInfo numberOfObjects];
}

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

    UITableViewCell *cell = [routineTableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
    }

    Exercise *tempExercise = (Exercise *)[fetchedResultsController objectAtIndexPath:indexPath];
    cell.textLabel.text = tempExercise.name;

    return cell;
}

-(void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
    if (editingStyle == UITableViewCellEditingStyleDelete) 
    {
        // Delete the managed object for the given index path
        NSManagedObjectContext *context = [self.fetchedResultsController managedObjectContext];
        [context deleteObject:[self.fetchedResultsController objectAtIndexPath:indexPath]];
        NSLog(@"fetched results : \n%@\n",[self.fetchedResultsController fetchedObjects]);

        // Commit the change.
        NSError *error = nil;

        // Update the array and table view.
        if (![fetchedResultsController.managedObjectContext save:&error]) 
        {
            // Handle the error.
        }
        //[tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:YES];
    }
}

- (void)configureCell:(UITableViewCell *)cell atIndexPath:(NSIndexPath *)indexPath
{
    NSManagedObject *managedObject = [self.fetchedResultsController objectAtIndexPath:indexPath];
    cell.textLabel.text = [[managedObject valueForKey:@"name"] description];
}

#pragma mark - Table view delegate

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    // Navigation logic may go here. Create and push another view controller.
    [routineTableView deselectRowAtIndexPath:indexPath animated:YES];
     DetailViewController *detailViewController = [[DetailViewController alloc] initWithNibName:@"DetailViewController" bundle:nil];
     // Pass the selected object to the new view controller.
     [self.navigationController pushViewController:detailViewController animated:YES];
     [detailViewController release];
}

#pragma mark - Fetched results controller

- (NSFetchedResultsController *)fetchedResultsController
{
    if (fetchedResultsController != nil)
    {
        return fetchedResultsController;
    }

    // Create the fetch request for the entity.
    NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
    // Edit the entity name as appropriate.
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Exercise" inManagedObjectContext:self.managedObjectContext];
    [fetchRequest setEntity:entity];
    NSLog(@"fetchedResultsController theSelectedRoutine: %@",theSelectedRoutine);
    [fetchRequest setPredicate:[NSPredicate predicateWithFormat: @"ANY exerciseToRoutine == %@", theSelectedRoutine]];

    // Set the batch size to a suitable number.
    [fetchRequest setFetchBatchSize:20];

    // Edit the sort key as appropriate.
    NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:NO];
    NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptor, nil];

    [fetchRequest setSortDescriptors:sortDescriptors];

    // Edit the section name key path and cache name if appropriate.
    // nil for section name key path means "no sections".
    NSFetchedResultsController *aFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:self.managedObjectContext sectionNameKeyPath:nil cacheName:nil];
    aFetchedResultsController.delegate = self;
    self.fetchedResultsController = aFetchedResultsController;

    NSError *error = nil;
    if (![self.fetchedResultsController performFetch:&error])
    {
        /*
         Replace this implementation with code to handle the error appropriately.

         abort() 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. If it is not possible to recover from the error, display an alert panel that instructs the user to quit the application by pressing the Home button.
         */
        NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
        abort();
    }

    [aFetchedResultsController release];
    [fetchRequest release];
    [sortDescriptor release];
    [sortDescriptors release];
    return fetchedResultsController;
}    

#pragma mark - Fetched results controller delegate

- (void)controllerWillChangeContent:(NSFetchedResultsController *)controller
{
    [self.routineTableView beginUpdates];
}

- (void)controller:(NSFetchedResultsController *)controller didChangeSection:(id <NSFetchedResultsSectionInfo>)sectionInfo
           atIndex:(NSUInteger)sectionIndex forChangeType:(NSFetchedResultsChangeType)type
{
    switch(type)
    {
        case NSFetchedResultsChangeInsert:
            [self.routineTableView insertSections:[NSIndexSet indexSetWithIndex:sectionIndex] withRowAnimation:UITableViewRowAnimationFade];
            break;

        case NSFetchedResultsChangeDelete:
            [self.routineTableView deleteSections:[NSIndexSet indexSetWithIndex:sectionIndex] withRowAnimation:UITableViewRowAnimationFade];
            break;
    }
}

- (void)controller:(NSFetchedResultsController *)controller didChangeObject:(id)anObject
       atIndexPath:(NSIndexPath *)indexPath forChangeType:(NSFetchedResultsChangeType)type
      newIndexPath:(NSIndexPath *)newIndexPath
{
    UITableView *tableView = self.routineTableView;

    switch(type)
    {

        case NSFetchedResultsChangeInsert:
            [tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] withRowAnimation:UITableViewRowAnimationFade];
            break;

        case NSFetchedResultsChangeDelete:
            [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
            break;

        case NSFetchedResultsChangeUpdate:
            [self configureCell:[tableView cellForRowAtIndexPath:indexPath] atIndexPath:indexPath];
            break;

        case NSFetchedResultsChangeMove:
            [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
            [tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath]withRowAnimation:UITableViewRowAnimationFade];
            break;
    }
}

- (void)controllerDidChangeContent:(NSFetchedResultsController *)controller
{
    [self.routineTableView endUpdates];
}

@end

更新，此方法位于另一个 viewController 中。这可能是导致问题的原因吗？

    - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
    {
        [tableView deselectRowAtIndexPath:indexPath animated:YES];

        NSString *selectedRow = [[self.exerciseArray objectAtIndex:indexPath.row]objectForKey:@"exerciseName"];
        NSLog(@"Row Selected: %@", selectedRow);

        RoutineDayTableViewController *routineDayTableViewController=[self.navigationController.viewControllers objectAtIndex:([self.navigationController.viewControllers count] -3)];

        routineDayTableViewController.selectedExercise = selectedRow;
        [routineDayTableViewController addExercise];
        [routineDayTableViewController release];

        [self dismissView];
  }

这是另一个 viewController 中访问此类的另一个方法：

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    [tableView deselectRowAtIndexPath:indexPath animated:YES];

     RoutineDayTableViewController *detailViewController = [[RoutineDayTableViewController alloc] initWithNibName:@"RoutineDayTableViewController" bundle:nil];
    NSManagedObject *managedObject = [self.fetchedResultsController objectAtIndexPath:indexPath];

    detailViewController.title = [[managedObject valueForKey:@"name"] description];

    detailViewController.theSelectedRoutine = [__fetchedResultsController objectAtIndexPath: indexPath];
    NSLog(@"detailViewController.theSelectedRoutine:%@",detailViewController.theSelectedRoutine);
    [self.navigationController pushViewController:detailViewController animated:YES];
    [detailViewController release];
}

Answer 1

该错误消息意味着您正在向其保留计数为零并随后被释放的对象发送消息。根据您的代码片段，我认为您的问题是这段代码 -

    RoutineDayTableViewController *routineDayTableViewController=[self.navigationController.viewControllers objectAtIndex:([self.navigationController.viewControllers count] -3)];

    routineDayTableViewController.selectedExercise = selectedRow;
    [routineDayTableViewController addExercise];
    [routineDayTableViewController release];

这里的 release 调用看起来很可疑。您正在释放一些未在此处分配的内容。

您对代码运行过静态分析器吗？它有助于检测此类错误。

Answer 2

RoutineDayTableViewController 类的实例是问题所在，因此它不太可能出现在您在此处发布的代码中。

检查使用此类的代码。

它可以帮助您使用“分析”选项进行构建，这通常可以检测到问题。

Answer 3

在某些地方，RoutineDayTableViewController 类的实例被释放，之后您尝试访问它。

如果您想检查，请不要释放该对象并尝试运行。