Question

I have a simple NSArray which has some arrays as objects which has some dates and strings as objects:

• NSArray (main array) —————> table view
  • NSArray (secondary array)—> table view cell
    • NSDate ——————–> table view cell text label
    • NSString ——————-> table view cell detail text label
    • etc.

I use the main array for my table view -> each cell got it’s own ‘secondary array’.
Now I want to sort the main array by the NSDate object. It sounds very easy but I have found no solution on the web for it.

I thought about using NSSortDesriptors but those just sort the array by the objects in the main array and not in the secondary array.

Hopefully you can help me

EDIT: Would it fix the problem if I use a NSDictionary as the secondary array?

Answer 1

You should be able to use NSArray sortedArrayUsingComparator if your app is targeted for iOS 4.0 or later:

NSArray *sortedArray = [mainArray sortedArrayUsingComparator: ^(id obj1, id obj2) {
    return [[obj1 objectAtIndex:0] compare:[obj2 objectAtIndex:0]];
}];

This assumes that the date field is always in index 0 of the internal array. It would probably be a bit cleaner if you used a dictionary and keyed the date field by name, but if you are comfortable with the date field always remaining in index 0 then the above should work.