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PONSmanaged context threads
 

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    <p>I use a singleton for working with arrays etc. cross the views in the application. </p> <p>To initialize the singleton and the <code>NSManagedObjectContext</code>, so that I can fetch objects, I use: </p> <pre><code>+(DataControllerSingleton *)singleDataController { static DataControllerSingleton * single=nil; @synchronized(self) { if(!single) { single = [[DataControllerSingleton alloc] init]; NSManagedObjectContext *context = [single.fetchedResultsController managedObjectContext]; single.masterCareList = [[NSMutableArray alloc] init]; } } return single; } </code></pre> <p>When I insert a new object that object will not show up in display functions until I restart the application. I insert new object through this method in the singleton class:</p> <pre><code>- (void)insertNewObject:(Care *)care { NSManagedObjectContext *context = [self.fetchedResultsController managedObjectContext]; NSEntityDescription *entity = [[self.fetchedResultsController fetchRequest] entity]; NSManagedObject *newManagedObject = [NSEntityDescription insertNewObjectForEntityForName: [entity name] inManagedObjectContext:self.managedObjectContext]; NSString *fileName = care.pictureURL; NSString *text = care.causeText; NSDate *date = care.date; NSData *imgData = care.imageData; [newManagedObject setValue:fileName forKey:@"urlPath"]; [newManagedObject setValue:text forKey:@"name"]; [newManagedObject setValue:date forKey:@"date"]; [newManagedObject setValue:imgData forKey:@"imageData"]; // Save the context. [self saveContext]; NSError *error = nil; if (![context save:&amp;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. NSLog(@"Unresolved error %@, %@", error, [error userInfo]); abort(); } } </code></pre> <p>My count method is the way I can tell that the new object is not included until I restart the application. The count method is also in the singleton as well. </p> <pre><code>- (NSUInteger)countOfList { NSArray *fetchedData = [_fetchedResultsController fetchedObjects]; return [fetchedData count]; } </code></pre> <p>When calling singleton I use: </p> <pre><code>DataControllerSingleton *singletonData = [DataControllerSingleton singleDataController]; [singletonData insertNewObject:care]; </code></pre> <p><code>managedObjectContext</code> property: </p> <p>.h: </p> <pre><code>@property (readonly, strong, nonatomic) NSManagedObjectContext *managedObjectContext; </code></pre> <p>.m:</p> <pre><code>@implementation DataControllerSingleton @synthesize managedObjectContext = _managedObjectContext; @synthesize managedObjectModel = _managedObjectModel; @synthesize persistentStoreCoordinator = _persistentStoreCoordinator; </code></pre> <p>Why will not my new object show up in ex count until I restart application? </p> <p>Am I somehow using different threads with different contexts, or different fethedResultsController or different singleton (shouldnt be possible right?)??</p> <hr> <p>I added these two lines, which are not included in the genereated CoreData Stack, and it now works fine. </p> <p>In singleton header: </p> <pre><code>@interface DataControllerSingleton : NSObject &lt;NSFetchedResultsControllerDelegate&gt; </code></pre> <p>In implementation file,</p> <pre><code>(NSFetchedResultsController *)fetchedResultsController { _fetchedResultsController.delegate = self; </code></pre>
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    1. COIn the line `NSManagedObject *newManagedObject = [NSEntityDescription insertNewObjectForEntityForName: [entity name] inManagedObjectContext:self.managedObjectContext];` you reference `self.managedObjectContext` but do not show anywhere in your code where you set that property
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    2. CO@ppilone I have a managedObjectContextProperty and synthesize in my singelton class. See updated question for code.
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    3. COI want to find the person who is recommending the use of singletons for data access :)
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