Magical Record exception while save One-To-Many Entity - xcode

Question

in my new App I have Core Data and Magical Record and this is how is structured the db:
This is the class corresponding to the entity NEWS:
#class SMCategories;
#interface SMNews : NSManagedObject
#property (nonatomic, retain) NSNumber * wpId;
#property (nonatomic, retain) NSString * title;
#property (nonatomic, retain) NSString * content;
#property (nonatomic, retain) NSString * url;
#property (nonatomic, retain) NSString * thumbnailUrl;
#property (nonatomic, retain) NSString * thumbnailFile;
#property (nonatomic, retain) NSDate * date;
#property (nonatomic, retain) SMCategories *category;
This is the class corresponding to the entity CATEGORIES:
#interface SMCategories : NSManagedObject
#property (nonatomic, retain) NSNumber * wpId;
#property (nonatomic, retain) NSString * name;
#property (nonatomic, retain) NSDate * lastUpdate;
#property (nonatomic, retain) NSSet *news;
#end
#interface SMCategories (CoreDataGeneratedAccessors)
- (void)addNewsObject:(NSManagedObject *)value;
- (void)removeNewsObject:(NSManagedObject *)value;
- (void)addNews:(NSSet *)values;
- (void)removeNews:(NSSet *)values;
This is the function I use to save, inside a cycle, all the datas that should be saved in the entity CATEGORIES:
- (void)saveUpdateCategories:(NSString *)result {
NSDictionary *tmpCategories = [result objectFromJSONString];
NSArray *categoriesList = [tmpCategories objectForKey:#"categories"];
NSDictionary *singleCategory;
NSPredicate * filter = [[NSPredicate alloc] init];
for(int i = 0; i < [categoriesList count];i++) {
singleCategory = [categoriesList objectAtIndex:i];
filter = [NSPredicate predicateWithFormat:#"wpId == %#",[singleCategory objectForKey:#"id"]];
SMCategories *checkCategory = [SMCategories MR_findFirstWithPredicate:filter];
[MagicalRecord saveWithBlock:^(NSManagedObjectContext *localContext) {
SMCategories *categoryToAdd;
if (checkCategory == nil) {
categoryToAdd = [SMCategories MR_createEntityInContext: localContext];
} else {
categoryToAdd = checkCategory;
}
categoryToAdd.name = [singleCategory objectForKey:#"name"];
categoryToAdd.wpId = [currentUtils stringToNumber:[singleCategory objectForKey:#"id"]];
categoryToAdd.lastUpdate = [currentUtils stringToDate:#"01/01/2000 00:00:01" formatted:#"dd/MM/yyyy HH:mm:ss"];
categoryToAdd.news = nil;
} completion:^(BOOL success, NSError *error) {
if (i == [categoriesList count] - 1) {
[progressWheel stopAnimating];
NSMutableDictionary *tmpOptions = [[NSMutableDictionary alloc] init];
tmpOptions = [currentUtils getDictionaryPlistFile:#"options.plist" path:[currentUtils getMainLocalPath]];
[tmpOptions setObject:[NSDate date] forKey:#"lastCategoriesUpdates"];
[currentUtils saveDictionaryPlistFile:tmpOptions fileName:#"options.plist" path:[currentUtils getMainLocalPath]];
[menuButton setEnabled:YES];
if (categoryToLoadPassed == nil)
categoryToLoadPassed = [SMCategories MR_findFirstByAttribute:#"name" withValue:DEFAULT_CATEGORY];
[self downloadNewsOfCategory:categoryToLoadPassed];
}
}];
}
}
This part of code works as well.
This is the funcion I use to save, inside another cycle, all the datas that should be inserted into the entity NEWS.
-(void) saveNewsOfCategory:(SMCategories *)category resultToSave: (NSString *) result {
NSDictionary *tmpNews = [result objectFromJSONString];
NSArray *newsList = [tmpNews objectForKey:#"posts"];
NSDictionary *singleNew;
NSPredicate * filter = [[NSPredicate alloc] init];
for(int i = 0; i < [newsList count];i++) {
singleNew = [newsList objectAtIndex:i];
filter = [NSPredicate predicateWithFormat:#"wpId == %#",[singleNew objectForKey:#"id"]];
SMNews *checkNew = [SMNews MR_findFirstWithPredicate:filter];
[MagicalRecord saveWithBlock:^(NSManagedObjectContext *localContext) {
SMNews *newToAdd;
if (checkNew == nil) {
newToAdd = [SMNews MR_createEntityInContext: localContext];
} else {
newToAdd = checkNew;
}
newToAdd.category = category;
newToAdd.title = [singleNew objectForKey:#"title"];
newToAdd.content = [singleNew objectForKey:#"content"];
newToAdd.wpId = [currentUtils stringToNumber:[singleNew objectForKey:#"id"]];
newToAdd.date = [currentUtils stringToDate:[singleNew objectForKey:#"date"] formatted:#"yyyy-MM-dd HH:mm:ss"];
newToAdd.url = [NSString stringWithFormat:#"%#?p=%#",WEBSITE,[singleNew objectForKey:#"id"]];
newToAdd.thumbnailFile = nil;
newToAdd.thumbnailUrl = [singleNew objectForKey:#"image"];
} completion:^(BOOL success, NSError *error) {
if (i == [newsList count] - 1) {
[MagicalRecord saveWithBlock:^(NSManagedObjectContext *localContext) {
category.lastUpdate = [NSDate date];
} completion:^(BOOL success, NSError *error) {
[progressWheel stopAnimating];
[currentTable reloadData];
}];
}
}];
}
}
Here it's thrown an exception EXT_BAD_ACCESS next to the line
newToAdd.category = category;
category is passed as one of the parameters of the corresponding function.
As you would have understood I have 2 entitis CATEGORIES and NEWS with a One-To-Many relationship.
First off I download all the categories and I store them into CATEGORIES entity when the user wants to download all the news of a specific category I download them and store with the second function into news entity passign into the second function the category of those specific news as parameters of my function.
If delete the line incriminated all the news are correctly store inside the database but they are not related to any cateogries.
What am I doing wrong?

Answer 1

The following line that threw an exception because I save the entity in a new Thread.
newToAdd.category = category;
So used a singleton class to get the category and set in that specific localcontex this way
SMCategories *currentCategory = [[DataManager getInstance] getCurrentCategory];
newsToAdd.category = [currentCategory MR_inContext:localContext];
Now everything works correctly.