Question

I have created an NSArray which I have initialized to contain the attributes of a core data entity. When I later try to set these attributes through the Array I get the error “!Expression is not assignable”. How do I set the values of the attributes by referencing them through the NSArray? Here are the relevant portions of my code:

    headingArray = [[NSArray alloc] initWithObjects:
                heading1,
                heading2,
                heading3, ...

heading1, heading2, … are attributes of the core data entity

    for (int i=1; [note.headingCount intValue]-1; i++) {
    [note.headingArray objectAtIndex:i] = selectedTemplateForNote.heading1;
  }

the [note.headingArray objectAtIndex:i] is the code that is flagged with the error “!Expression is not assignable”.

Answer 1

NSArray are immutable. You can not change their content without constructing a new array. Try using an NSMutableArray and - (void)replaceObjectAtIndex:(NSUInteger)index withObject:(id)anObject; instead.

Editing based on new info:

You are probably trying to do the following then:

NSManagedObject *entity = ...;
for (int i=1; [note.headingCount intValue]-1; i++) {
    [entity setValue:selectedTemplateForNote.heading1 forKey:[note.headingArray objectAtIndex:i]];
}