1. Mobile City: Core Data
TaskList

2. About Me
● Allan Davis
– Lead Developer of Mobile Technology for
DealerMatch
– Cajun.code@gmail.com
– @cajun_code

3. Session Agenda
● Introduction(Tip Calculator)
● Overview of Objective C(TicTacToe)
● UI UX (TrackerPoker)
● CoreData (MyBloodyTaskList)
● Networking and web-services
(TrackerPokerLive)
● Debugging, Testing, Tuning and Distribution
● Game Development with Cocos2d (Oni Attack)

4. Class Agenda
● What is CoreData
● Create the Data Model
● NSManagedObjectContext
● UIManagedDocument
● AppDelegate
● Generate Object Models
● Create
● Read
● Update
● Delete
● NSFetchedResultsController

5. What is Core Data
● Object Relational Management tool.
● How does it work?
– Create a visual mapping of database to objects
– Create query for objects using object-oriented API
– Access the “columns in the database table” using
properties on the objects

6. Creating the Data Model

7. Create Model Visually

8. NSManagedObjectContext
● Session Management object where all activity
turns.
● Two ways to create one.
– Create a UIManagedDocument and ask for the
context
– Property off the AppDelegate if you selected “Use
Core Data” when you created the project

9. UIManagedDocument
● Create Property for UIManagedDocument
- (void)useDocument
{
if (![[NSFileManager defaultManager] fileExistsAtPath:[self.photoDatabase.fileURL path]]) {
// does not exist on disk, so create it
[self.photoDatabase saveToURL:self.photoDatabase.fileURL
forSaveOperation:UIDocumentSaveForCreating completionHandler:^(BOOL success) {
[self setupFetchedResultsController];
[self fetchFlickrDataIntoDocument:self.photoDatabase];
}];
} else if (self.photoDatabase.documentState == UIDocumentStateClosed) {
// exists on disk, but we need to open it
[self.photoDatabase openWithCompletionHandler:^(BOOL success) {
[self setupFetchedResultsController];
}];
} else if (self.photoDatabase.documentState == UIDocumentStateNormal) {
// already open and ready to use
[self setupFetchedResultsController];
}
}

10. AppDelegate
● Generated by Xcode
● Need to push context down to down to
ViewController
UINavigationController *navigationController = (UINavigationController *)self.window.rootViewController;
UIViewController *controller = navigationController.topViewController;
[controller performSelector:@selector(setManagedObjectContext:) withObject:self.managedObjectContext];

11. Generate Classes from Model

12. Create
Trim *trim = [NSEntityDescription insertNewObjectForEntityForName:@"Trim"
inManagedObjectContext:context];

13. Read
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription
entityForName:@"Task" inManagedObjectContext:context];
[fetchRequest setEntity:entity];
fetchRequest.predicate =
[NSPredicate predicateWithFormat:@"category.name = %@", category.name];
fetchRequest.sortDescriptors =
@[[NSSortDescriptor sortDescriptorWithKey:@"name" ascending:YES]];
[context executeFetchRequest:fetchRequest error:&error];

14. Update
● Make changes to property
● Call save on the ManagedObjectContext

15. Delete
● Call delete on the ManagedObjectContext and
pass in the object to delete

16. NSFetchRequestController
● Adds functionality to monitor a FetchRequest
to update a table view.

17. TaskList
● Simple Task List
● Sorted by Category

18. Resources
● Stanford CS 193P
– Lecture 13 and 14 are Core Data
– http://www.stanford.edu/class/cs193p/cgi-bin/drupal/
● Class Links
– Videos: http://vimeo.com/channels/mobilecity
– Slides: http://www.slideshare.net/javaalley/
– Code:
https://github.com/organizations/AtlantaMobileDevGroup