Sorting mutable array by dictionary key

Question

I have already looked through a few answers using the various sorting methods of `NSMutableArray`, but for some reason they are not working for me. I am just trying to sort the mutable array which contains dictionaries by the `Delay` key within each dictionary. However, the "sorted" array is the exact same as the original array. By the way, it works fine if I create a dummy mutable array and populate it with dictionaries containing numbers, but for some reason it won't sort this mutable array that I am initializing. What am I doing wrong? Here's my code: ``` playlistCalls = [[NSMutableArray alloc] initWithArray:[currentPlaylist objectForKey:@"Tunes"]]; NSLog(@"original %@", playlistCalls); NSSortDescriptor *delay = [NSSortDescriptor sortDescriptorWithKey:@"Delay" ascending:YES]; [playlistCalls sortUsingDescriptors:[NSArray arrayWithObject:delay]]; NSLog(@"sorted %@", playlistCalls); ``` Here's the array containing the dictionaries: ``` 2012-06-04 15:48:09.129 MyApp[57043:f503] origina…

Accepted Answer

The code above is fine when I use `NSNumber`s in my dictionary. That leads me to believe that the `Delay` value is stored as strings in your dictionary. What you will need to do then is sort by the strings `integerValue`.

```
NSSortDescriptor *delay = 
   [NSSortDescriptor sortDescriptorWithKey:@"Delay.integerValue" ascending:YES];
```

Sorting mutable array by dictionary key

Solution

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