ios - 删除 NSManagedObject 时无法识别的选择器

Question

我想通过先获取对象来删除核心数据对象，所以

在 FetchObject.m 中

- (void) actionDelete {
    AModel *aModel = [[aModel alloc] init];
    AObj *aObj = [aModel readDataWithAttributeName:@"keyword" attributeValue:@"value"];

    [aModel deleteObject:aObj];
}

aObj 确实获取并获得了。
在 AModel.m 中

- (void)deleteObject:(AObj *)aObj
{
    [appDelegate.managedObjectContext delete:aObj];
    NSError *error;
    if (![appDelegate.managedObjectContext save:&error]) {
        NSLog(@"Error: %@", [error description]);
    }
}

但是，当我测试它的时候，这里出现了一个错误

-[NSManagedObjectContext delete:]: unrecognized selector sent to instance 0xa43ece0

稍微搜索一下解决方案后，似乎目标已在 deleteObject 之前被释放。有什么办法可以解决这个问题吗？

Answer 1

以下代码导致了问题:

[appDelegate.managedObjectContext delete:aObj];

替换为:

[appDelegate.managedObjectContext deleteObject:aObj];

NSManagedObjectContext没有delete方法，它只有一个deleteObject方法。

- (void)deleteObject:(NSManagedObject *)object

Parameters

object

A managed object.

Discussion

When changes are committed, object will be removed from the uniquing tables. If object has not yet been saved to a persistent store, it is simply removed from the receiver.