Any way to pre populate core data?

Here's the best way (and doesn't require SQL knowledge):
Create a quick Core Data iPhone app (Or even Mac app) using the same object model as your List app. Write a few lines of code to save the default managed objects you want to the store. Then, run that app in the simulator. Now, go to ~/Library/Application Support/iPhone Simulator/User/Applications. Find your application among the GUIDs, then just copy the sqlite store out into your List app's project folder.

Then, load that store like they do in the CoreDataBooks example.

Yes there is in fact the CoreDataBooks example does this, you can download the code here: sample code

What you do is create the internal store (database) using the normal procedure to initialize your store just like you would with any other store, then you simply run your code and let it execute the code as described in the CoreDataBooks example (code snippet below). Once the store has been initialized you will want to create a NSManagedObjectContext and initialize it with the created persistent store, insert all the entities you need, and save the context.

Once the context has been successfully saved, you can stop your application, then go to finder and go to folder: ~/Library/Developer type in the search .sqlite and look under /Developer, sorting by date will give you the most recent .sqlite database which should match the time that the code was executed, you can then take this store and add it as a resource of your project. This file then can be read by a persistent store coordinator.

- (NSPersistentStoreCoordinator *)persistentStoreCoordinator {

if (persistentStoreCoordinator) {
    return persistentStoreCoordinator;
}


NSString *storePath = [[self applicationDocumentsDirectory]      stringByAppendingPathComponent: @"CoreDataBooks.sqlite"];
 /*
  Set up the store.
 For the sake of illustration, provide a pre-populated default store.
 */
NSFileManager *fileManager = [NSFileManager defaultManager];
// If the expected store doesn't exist, copy the default store.
if (![fileManager fileExistsAtPath:storePath]) {
  NSString *defaultStorePath = [[NSBundle mainBundle] pathForResource:@"CoreDataBooks"      ofType:@"sqlite"];
 if (defaultStorePath) {
 [fileManager copyItemAtPath:defaultStorePath toPath:storePath error:NULL];
 }
}

NSURL *storeUrl = [NSURL fileURLWithPath:storePath];

 NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:[NSNumber   numberWithBool:YES], NSMigratePersistentStoresAutomaticallyOption, [NSNumber numberWithBool:YES], NSInferMappingModelAutomaticallyOption, nil]; 
  persistentStoreCoordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel: [self managedObjectModel]];

 NSError *error;
 if (![persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:storeUrl options:options error:&error]) {
  // Update to handle the error appropriately.
  NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
 exit(-1);  // Fail
}    

return persistentStoreCoordinator;
}

Hope that helps.

-Oscar

With this method you don't need to make a separate app or have any SQL knowledge. You only need to be able to make a JSON file for your initial data.

I use a JSON file that I parse into objects, then insert them in Core Data. I do this when the app initializes. I also make one entity in my core data that indicates if this initial data is already inserted, after I insert the initial data I set this entity so the next time the script runs it sees that the initial data has already been initialized.

To read json file into objects:

NSString *initialDataFile = [[NSBundle mainBundle] pathForResource:@"InitialData" ofType:@"json"];
NSError *readJsonError = nil;
NSArray *initialData = [NSJSONSerialization
                        JSONObjectWithData:[NSData dataWithContentsOfFile:initialDataFile]
                        options:kNilOptions
                        error:&readJsonError];

if(!initialData) {
    NSLog(@"Could not read JSON file: %@", readJsonError);
    abort();
}

Then you can make entity objects for it like this:

[initialData enumerateObjectsUsingBlock:^(id objData, NSUInteger idx, BOOL *stop) {

    MyEntityObject *obj = [NSEntityDescription
                          insertNewObjectForEntityForName:@"MyEntity"
                          inManagedObjectContext:dataController.managedObjectContext];

    obj.name = [objData objectForKey:@"name"];
    obj.description = [objData objectForKey:@"description"];

    // then insert 'obj' into Core Data

}];

If you want a more detailed description on how to do this, check out this tutorial: http://www.raywenderlich.com/12170/core-data-tutorial-how-to-preloadimport-existing-data-updated

For 10 items, you can just do this within applicationDidFinishLaunching: in your app delegate.

Define a method, say insertPredefinedObjects, that creates and populates the instances of the entity in charge of managing your airport items, and save your context. You may either read the attributes from a file or simply hardwire them in your code. Then, call this method inside applicationDidFinishLaunching:.

Bear in mind, when following the CoreDataBooks example code, that it probably breaks the iOS Data Storage Guidelines:

https://developer.apple.com/icloud/documentation/data-storage/

I've had an app rejected for copying the (read-only) pre-populated database to the documents directory - as it then gets backed up to iCloud - and Apple only want that to happen to user-generated files.

The guidelines above offer some solutions, but they mostly boil down to:

store the DB in the caches directory, and gracefully handle situations where the OS purges the caches - you will have to rebuild the DB, which probably rules it out for most of us.
set a 'do not cache attribute' on the DB file, which is a little arcane, as it needs to be done differently for different OS versions.

I don't think it is too tricky, but be aware that you have a bit extra to do to make that example code work alongside iCloud...

Any way to pre populate core data?

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