How to get address the object of an related entity with CoreData ?
- by eemceebee
Hi
Ok, after I ran into a dead end modifieing an existing Apple example for CoreData, I started completely new creating my own project and that worked fine,..... until I tried to access a related entity.
So here is what I did.
I created 2 entities, where one is just the detail information of the other one, so there is a one-2-one relationship.
Entity #1, Stocks:
name
value
details -- relationship to Entity #2
Entity #2, StockDetails:
bank
published
stock -- relationship to Entity #1
Now, I created the "Managed Object Class" for both of the Entities.
Then I created a few lines to put some data into it
NSManagedObjectContext *context = [self managedObjectContext];
Stocks *stockinfo= [NSEntityDescription
insertNewObjectForEntityForName:@"Stocks"
inManagedObjectContext:context];
stockinfo.name = @"Apple";
stockinfo.value = [NSNumber numberWithInt:200];
StockDetails *thestockdetails = [NSEntityDescription
insertNewObjectForEntityForName:@"StockDetails"
inManagedObjectContext:context];
thestockdetails.bank = @"Bank of America";
thestockdetails.published = [NSDate date];
thestockdetails.stock = stocks_;
stockinfo.details = thestockdetails ;
NSError *error;
if (![context save:&error])
{
NSLog(@"A Problem occured, couldn't save: %@", [error localizedDescription]);
}
Just want to mention here, that I do not get an error with this.
Next I put everything into a UITableViewController for a preview and another for a detail view. The preview just shows infos form Entity #1 (Stocks) and when selected it shows the detail view.
Now here I also display the infos form Entity #1 (Stocks) but I want to show the Entity #2 (StockDetails) aswell.
This is how I try to access the data :
StockDetails *details_ = [stockinfo details];
And this gives me a EXC_BAD_ACCESS.
So any idea what I am doing wrong here ?
Thanks
