尝试插入 CoreData 时发送到实例的无法识别的选择器

Question

我正在尝试将一些数据保存到 CoreData，但出现错误：

Restaurant Manager[5971:60b] * 由于未捕获的异常“NSInvalidArgumentException”而终止应用程序，原因：“-[ProdusComandat setIdProdus:]：无法识别的选择器已发送到实例 0x90b8270”

谁能告诉我为什么？

 SessionController* sessionController = [[SessionController alloc]init];

NSFetchRequest *fetchRequest = [NSFetchRequest fetchRequestWithEntityName:@"ComenziActive"];// baza de date
[fetchRequest setPredicate:[NSPredicate predicateWithFormat:@"numeClient == %@",sessionController.getSessionUsername]];

NSError *err;
NSUInteger count = [self.managedObjectContext countForFetchRequest:fetchRequest error:&err];

NSArray *listaElementeBD = [[NSArray alloc]init];


if(count <= 0)
{
    NSEntityDescription *entitydesc;
    entitydesc = [NSEntityDescription entityForName:@"ComenziActive" inManagedObjectContext:self.managedObjectContext];

    ComenziActive *comanda = [NSEntityDescription insertNewObjectForEntityForName:@"ComenziActive" inManagedObjectContext:self.managedObjectContext];

    [comanda setValue:sessionController.getSessionUsername forKey:@"numeClient"];

    ProdusComandat * produsComandat = [[ProdusComandat alloc]init];
    produsComandat.idProdus = [[[(Produs*)produsdb objectID] URIRepresentation] absoluteString];
    produsComandat.cantitateComandata = [NSNumber numberWithInteger:[self.cantitateTextField.text integerValue]];

    [comanda addProduseComandateObject:produsComandat];

}
else
{

    NSError *error;
    listaElementeBD = [self.managedObjectContext executeFetchRequest:fetchRequest error:&error];
    ComenziActive *comanda = [listaElementeBD objectAtIndex: 0];

    NSArray *produse = comanda.produseComandate.allObjects;
    BOOL found =NO;
    for(int i=0;i<[produse count];i++)
    {
        ProdusComandat *p =[[ProdusComandat alloc]init];
        p= produse[i];
        if ([p.idProdus isEqualToString:[[[(Produs*)produsdb objectID] URIRepresentation] absoluteString]]) {
            p.cantitateComandata = [NSNumber numberWithInteger:[p.cantitateComandata integerValue] + [self.cantitateTextField.text integerValue]];
            found = YES;
            break;
        }
    }
    if (!found) {
        ProdusComandat * produsComandat = [[ProdusComandat alloc]init];
        produsComandat.idProdus = [[[(Produs*)produsdb objectID] URIRepresentation] absoluteString];
        produsComandat.cantitateComandata = [NSNumber numberWithInteger:[self.cantitateTextField.text integerValue]];

        [comanda addProduseComandateObject:produsComandat];
    }


    NSLog(@"============================");
    NSLog(@"%@", comanda.produseComandate );
}


NSError *error;
[self.managedObjectContext save:&error];

我要做的是从 CoreData 实体 Produs 获取数据并将其 objectID 复制到实体 ProduseComandate 具有这种关系 ComenziActive>ProduseComandate（关系一对多）如果 objectID 不存在于表中，但如果它确实存在，我想将我从 TextField 中获取的一些值添加到值 cantiate。

Answer 1

问题是我需要这样声明：

ProdusComandat *produsComandat = [[ProdusComandat alloc]initWithEntity:entity insertIntoManagedObjectContext:self.managedObjectContext];