Hello, I am working with an undocumented API (Osirix) and I have a sister-question to the one I posted here. I am having trouble loading objects from a managed object context. With loading from API, using their instance of _context and _model 2010-05-28 14:05:13.588 OsiriX[44012:a0f] Entity: Study 2010-05-28 14:05:13.589 OsiriX[44012...
I am new at Core Data, and it seems like it is a great way to manage the data store. However I am also very memory-conscious due to the fact that the iPhone doesn't have that much of it. I was a little surprised to see that the data types are so limited - eg. there is a Date type which includes also the time, but no Date type for just th...
Lets say I have a RSS feed which lists the 3 newest questions on SO. At 1 o'clock, the feed looks like this: While making an RSS reader which saves articles, how can I prevent duplicates? Convert char array to UNICODE in MFC C++ How to deploy a Java Swing application with an embedded JavaDB database? At 2 o'clock, this feed looks lik...
I have a Core Data entity which has a date attribute. I would like to write a predicate to extract all dates within a specific month, e.g. July, irrespective of year. How can this be achieved? Thanks ...
Sometimes I noticed that a 'save:' operation an a ManagedObjectContext never returns and consumes 100% CPU. I'm using an SQL Store in a GarbageCollected environment (Mac OS X 10.6.3). The disk activity shows about 700 KB/s writing. While having a look at the folder that contains the sqlite database file the "-journal" file appears and d...
I apologize ahead of time for what I'm sure is a complete newbie lapse. Running my iPhone app on iPhone simulator - no problem. But I loaded the app on an iPhone device for the first time and it appears as if the SQLite database I'm using (NSManagedObjectContext) isn't connected or didn't upload. The app installs but with no data. How do...
I'm using Core Data to store a lot (1000s) of items. A pair of properties on each item are used to determine uniqueness, so when a new item comes in, I compare it against the existing items before inserting it. Since the incoming data is in the form of an RSS feed, there are often many duplicates, and the cost of the uniquing step is O(N...
I have set up one of my core data attributes as a Boolean. Now, I need to set it, but XCode keeps telling me that it may not respond to setUseGPS. [ride setUseGPS: useGPS.on]; What is the method for setting a boolean in core data? All my other attributes are set this way, and they work great. So, not sure why a boolean does not wor...
I am using core data trying to create a simple database app, I have an entity called "Game" which has a "creator". I have basically used the iPhone table view template and replaced the names. I have the games listed by creator. Currently the tableview looks like this... Chris Ryder Chris Ryder Chris Ryder Chris Ryder Dan Grimaldi Dan G...
Hi. i am a noob in xcode. I am developing an iphone app where i need to send and receive data from a web service. And i need to store them temporarily in my app. i dont want to use sqlite. so i was wondering if i should use core data for this purpose. I read some articles but i still dont have a clear picture of how to do it, coz i have ...
I am getting an exception when I try to get @sum on a column in iPhone Core-Data application. My two models are following - Task model: @interface Task : NSManagedObject { } @property (nonatomic, retain) NSString * taskName; @property (nonatomic, retain) NSSet* completion; @end @interface Task (CoreDataGeneratedAccessors) - (void...
Okay, so I have a fairly simple application set up. I have two different CoreData Entities, Games and Platforms, each have one attribute: name, and they have a one-to-many relationship between them. Platforms are populated on the first launch of the application, and will never change as a result of user input. I'm working on my Add vi...
I would like to replicate the notification sort of system provided with CoreData NSFetchedResultController which with really little enables us to update a tableView based on events such as Insert/Update/Delete of objects represented as Cells. I'm currently using SQLitePersistentObjects as a Database abstraction layer: http://code.googl...
What advantage is there to implementing the four delegate methods: (void)controllerWillChangeContent:(NSFetchedResultsController *)controller (void)controller:(NSFetchedResultsController *)controller didChangeSection:(id )sectionInfo atIndex:(NSUInteger)sectionIndex forChangeType:(NSFetchedResultsChangeType)type (void)controller:(NSFet...
Hello, I have a 2 tabs application. In the first one, I'm creating objects of the "Sample" and "SampleList" entities. Each sampleList contains an ID and a set of samples. Each sample contains a date and temperature property. In the second tab, I'm displaying my data in a tableView. I implemented the - (void)tableView:(UITableView *)...
I'm trying to figure out why insertNewObjectForEntityForName is not working. I assume it's something to do with my data model but can't be sure. Xcode does not report any errors nor does it crash. All I get is the first log statement output to the console. NSLog(@"Get here..."); Task *task = (Task *)[NSEntityDescription insertNewObjectF...
When I define a to many relationship between entities in Xcode and then generate the data class from the entity I get a header with the following methods defined: @interface PriceList (CoreDataGeneratedAccessors) - (void)addItemsObject:(PriceListItem *)value; - (void)removeItemsObject:(PriceListItem *)value; - (void)addItems:(NSSet *)va...
Hi I have a app that works with Core Data. The data has a field with a date and I would like to show every entry of a month in a seperate section. How do I actually get the data ? I use a NSFetchedResultsController to get the data and use this : - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section ...
Hello, if this has been asked and answered please point me out to the right direction! i m playing around with the iphoneCoreDataRecipes Apple sample code and trying to implement a UISearchBar. what i have done is created a searchcontroller and populated it s contents with a master list. here is the code: // Customize the appearance ...
I want to use Core Data on the iPhone. Do you know great tutorials, videos and ressources for learning Core Data in depth? ...