' entityForName: nil is not a legal NSManagedObjectContext -CoreData - iphone

Question

I am getting this error when running the app:
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason:
'+entityForName: nil is not a legal NSManagedObjectContext parameter searching for entity
name 'Event''
This is my TimeTableController.h file (TimeTableController is a subclass UITableViewController and app loads this file when app stared.
TimeTableController.h:
#import "Event.h"
#interface TimeTableController : UITableViewController
{
NSManagedObjectContext *managedObjectContext;
NSMutableArray *eventArray;
}
#property (nonatomic, retain) NSManagedObjectContext *managedObjectContext;
#property (nonatomic, retain) NSMutableArray *eventArray;
- (void) fetchRecords;
- (void) addTime:(id)sender;
#end
Event.h and Event.m are my model files.
And TimeTableController.m
- (void)viewDidLoad
{
[super viewDidLoad];
self.title = #"Lap Times";
UIBarButtonItem *addButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:#selector(addTime:)];
self.navigationItem.rightBarButtonItem = addButton;
//[addButton release];
[self fetchRecords];
// Uncomment the following line to preserve selection between presentations.
// self.clearsSelectionOnViewWillAppear = NO;
// Uncomment the following line to display an Edit button in the navigation bar for this view controller.
// self.navigationItem.rightBarButtonItem = self.editButtonItem;
}
-(void)fetchRecords {
// This line gives the error
NSEntityDescription *entity = [NSEntityDescription entityForName:#"Event" inManagedObjectContext:managedObjectContext];
}
The line in fetchRecords method is giving the error.
And this is my AppDelegate.m file:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
// Override point for customization after application launch.
TimeTableController *tableController = [[TimeTableController alloc] initWithStyle:UITableViewStylePlain];
tableController.managedObjectContext = [self managedObjectContext];
self.navigationController = [[UINavigationController alloc] initWithRootViewController:tableController];
//[tableController release];
[window addSubview: [self.navigationController view]];
[window makeKeyAndVisible];
return YES;
}
When I've created the project,Data Model file didn't exist so I've added the Data Model file (LapTimer.xcdatamodeld) to existing project.
I tried all solutions I found and I have no idea why I am getting this error now.
Note: I know there are a lot of threads that cover exactly this questions. I looked at all but none of answers didn't work for me.

Answer 1

I was getting the same error message and it turns out that managedObjectContext was nil.