Question

I want to add 10 elements to a Core Data store.

The problem is that only the last element is added.

NSEntityDescription *entity = [NSEntityDescription entityForName:@"Test" inManagedObjectContext:[self managedObjectContext]]; 
Test *test = [[[Test alloc] initWithEntity:entity insertIntoManagedObjectContext:[self managedObjectContext]] autorelease];        

for (int i =0; i<10; i++) 
{
    test.text = @"Text";
    test.index = [NSNumber numberWithInt:i];
    [self saveContext];
}

Answer 1

You must insert test into the context inside of the loop, not before it:

NSEntityDescription *entity = [NSEntityDescription entityForName:@"Test" inManagedObjectContext:[self managedObjectContext]];
for (int i = 0; i < 10; i++) {
   Test *test = [[[Test alloc] initWithEntity:entity insertIntoManagedObjectContext:[self managedObjectContext]] autorelease];
  test.text = @"Text";
  test.index = [NSNumber numberWithInt:i];
  [self saveContext];
}

Also, I would save the context outside of the loop for performance reasons. You need only to save it once, not every time.