CoreData error how to write core data back

Question

I am just trying to wrap my head around core data. I have managed to load some data into it i applicationDidFinishLaunching but now I want to do something a little more complicated. When I unwind from view controller B back to viewController A, I want to send the recipeName from B back to A and then write it to core data. I get this error:

CoreData: error: Failed to call designated initializer on NSManagedObject class 'Recipe' 2013-11-01 19:10:07.886 RecipesWithCore[96409:70b] -[Recipe setRecipeName:]: unrecognized selector sent to instance 0x8c8cf40 2013-11-01 19:10:07.890 RecipesWithCore[96409:70b] * Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[Recipe setRecipeName:]: unrecognized selector sent to instance 0x8c8cf40'

This is my unwindToRecipes:

-(IBAction) unwindToRecipes:(UIStoryboardSegue *)segue{
    DBKAddRecipeViewController *source = [segue sourceViewController];

    NSString *rn = source.recipe.recipeName;
    if (recipe != nil){
        //Add the recipe to coredata

        NSManagedObjectContext *context = [self managedObjectContext];
        NSManagedObject *newRecipe = [NSEntityDescription
                                   insertNewObjectForEntityForName:@"Recipe"
                                   inManagedObjectContext:context];

        [newRecipe setValue:rn forKey:@"recipeName"];

    }
}

looks like your RecipeName is not a property of your managed object subclass... — Petro Korienev

Mundi Mundi · Accepted Answer · 2013-11-02T09:25:56

It seems that insertNewObject returns a Recipe class, not a NSManagedObject. Check your Recipe class and make sure you have the correct declarations in its @interface, as well as @dynamic recipeName in its @implementation. Also check your managed object model and make sure the attribute name is indeed recipeName.

CoreData error how to write core data back

1 Answers