Question

I created my app using Core Data, declared 2 attributes, SongLyrics and MovieSongName, both as string. Then in xib I created a text field for MovieSongName and a text view for SongLyrics. For storing these I used the following code

-(void)saveData
{
    LyricsAppDelegate *appDelegate = [[UIApplication sharedApplication] 
                                  delegate];

    NSManagedObjectContext *managedObjectContext = [appDelegate managedObjectContext];
    NSEntityDescription *entityDesc = [NSEntityDescription    
                                       entityForName:@"Lyrics"        
                              inManagedObjectContext:managedObjectContext];
    NSManagedObject *LyricsObjectEnglish;
    LyricsObjectEnglish = [NSEntityDescription    
                           insertNewObjectForEntityForName:@"English_Songs"   
                                    inManagedObjectContext:managedObjectContext];
   [LyricsObjectEnglish setValue:song_lyrics.text forKey:@"SongLyrics"];
   [LyricsObjectEnglish setValue:song_name forKey:@"MovieSongName"];

   song_lyrics.text=@"";
   song_name.text=@"";
   NSError *error; 
   [managedObjectContext save:&error];
}

when clicking on the save button app gets aborted with the following error.

2012-01-27 10:50:52.071 Lyrics[4624:207] * Terminating app due to uncaught exception ‘NSInvalidArgumentException’, reason: ‘Unacceptable type of value for attribute: property = “MovieSongName”; desired type = NSString; given type = UITextField; value = >.’

Can any one help me? I’m using Core Data for the first time and I’m a little confused.

Answer 1

The error is telling you exactly what the problem is. Specifically, MovieSongName needs an NSString value, but the value you are giving it is a UITextField because you are trying to give it song_name rather than song_name.text.

The correct code is:

[LyricsObjectEnglish setValue:song_name.text forKey:@"MovieSongName"];