从CoreData获取NSSet并将其显示在Label中

Question

i have an nsset of room attributes(NSString), i stored them in CoreData. how can i fetch them to show it in a UILabel?

i tried this in viewDidLoad:

    NSArray *array = [[currentRaum raumattribute] allObjects];

    [roomAttributLabel setText:[NSString stringWithFormat:@"%@",array]];

but it didn't work. it shows some core data code Screenshot

this is how i save my content:

Raum *raum2 = [NSEntityDescription insertNewObjectForEntityForName:@"Raum" inManagedObjectContext:context];


raum2.raumName = @"Main";
raum2.ort = @"Aschaffenburg";
raum2.strasse = @"Bruchtannenstr. 11";
raum2.etage = @"2. Stock, Raum 1.203";
raum2.beschreibung = @"Gut beleuchtet";

UIImage *img2 = [UIImage imageNamed:@"Main.jpg"];
NSData *data2 = UIImagePNGRepresentation(img2);
raum2.foto = data2;


NSSet *attributeFurRaum2 = [NSSet setWithObjects:attribute4,attribute5,attribute6,nil];

raum2.raumattribute= attributeFurRaum2;

Declaration of currentRaum:

 self.currentRaum = [self.fetchedResultsController objectAtIndexPath:indexPath];

i expected 3 different NSStrings which are saved like this:

Raumattribute *attribute4 =[NSEntityDescription    insertNewObjectForEntityForName:@"Raumattribute" inManagedObjectContext:context];
attribute4.attributname = @"Copyboard";


Raumattribute *attribute5 =[NSEntityDescription insertNewObjectForEntityForName:@"Raumattribute" inManagedObjectContext:context];
attribute5.attributname = @"Flipchart";


Raumattribute *attribute6 =[NSEntityDescription insertNewObjectForEntityForName:@"Raumattribute" inManagedObjectContext:context];
attribute6.attributname = @"Internetmöglichkeit";

Answer 1

You're going to have to iterate through the array elements to add them to your string. Depending on how you want the string to look, it might be something like:

NSString *compositeString = [ [ NSString alloc ] init ];
for( RaumAttribute *attr in array )
    compositeString = [ NSString stringWithFormat:@"%@ %@", compositeString, RaumAttribute.attributeName ];
[roomAttributLabel setText:compositeString];

if I have the field name right. I can't see the question while editing the answer...