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POCorrect way to add relational data to Core Data
 

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  1. POCorrect way to add relational data to Core Data
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    <p>I've created two objects in my model, Account and Friend - where 1 Account will have many Friends. I have created these two objects in code also.</p> <p>I am using a UITableView to show my Accounts (all fine), and using a new UIViewController to add a new record. In the new record I am adding the Account details, and getting friends from an API. When going from the UITableView to the new UIViewController I am creating an empty Account object: UIViewController.account = account;</p> <p>Now the tricky part. When saving this data I am doing the following:</p> <pre><code>// Configure the new account with information from the form. [account setUsername:[profileDict objectForKey:@"the_name"]]; [account setPassword:password.text]; // from formfield [account setCreationDate:[NSDate date]]; // Commit the change. NSError *error; if (![account.managedObjectContext save:&amp;error]) { // Handle the error. NSLog(@"save error"); } NSManagedObjectContext *context = [account managedObjectContext]; for(NSArray *names in usernameArray) //usernameArray holds my Friends { friend = [NSEntityDescription insertNewObjectForEntityForName:@"Friend" inManagedObjectContext:context]; [account addReplyAccountsObject:friend]; [friend setName:[names objectAtIndex:0]]; [friend setPicUrl:[names objectAtIndex:1]]; // Commit the change. NSError *error; if (![context save:&amp;error]) { // Handle the error. NSLog(@"save error"); } } </code></pre> <p>Now this seems to work - however sometimes my app crashes with a bus error - usually on the device rather than the simulator. Is this the right way to save an Account and many Friends at once? Also - any reason why I would get a bus error? It seems to happen when there are many Friends....</p>
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