CODEWITHSUNDEEP
iphoneobjective-cnsmutablearray
Aisha
Aisha

Reputation: 1559

rearranging values in an array

I have an array of dictionaries.

Each dictionary have a key "color" and the possible values of color are "red", "green", "blue", "yellow". In the array the dictionaries are added in the order that on fetching the value for key "color" we get "yellow", "green","red" and "blue".

Edit: 

I have an array objectsArray of dictionaries.
for(int i=0,i<[objectsArray count];i++)
{
  NSDictionary *dict = [objectsArray objectAtIndex:i];
  NSLog(@"color: %@\n",[dict valueForKey:@"color"]); //
}
Output: 
yellow
green
red 
blue

I want output to be
red
green
blue
yellow

How can I do so. Any suggestions. Thanx in advance.

Upvotes: 2

Views: 240

Answers (3)

Zapko
Zapko

Reputation: 2461

NSMutableArray *newArray = [objectsArray mutableCopy]
[newArray exchangeObjectAtIndex:3 withObjectAtIndex:4];
[newArray exchangeObjectAtIndex:0 withObjectAtIndex:4];
[objectsArray release];
objectsArray = newArray;

hope this'll help!

Upvotes: 1

Joetjah
Joetjah

Reputation: 6132

'Stole' this from the answer on my own question:

If your array is mutable, you can sort it using the -sortUsing... methods. If not, you can create a new, sorted array using the -sortedArrayUsing... methods. For example, there are -sortUsingComparator: and -sortedArrayUsingComparator: methods which take a comparator block as a parameter. You just need to supply a block that compares two objects using your custom sort order, like this:

[myArray sortUsingComparator:^(id firstObject, id secondObject) {     
    NSString *firstKey = [firstObject valueForKey:@"color"];     
    NSString *secondKey = [secondObject valueForKey:@"color"];
    if ([firstKey stringEqual:@"red"] || [lastKey stringEqual:@"green"])
         return NSOrderedAscending;
    else if ([firstKey stringEqual:secondKey])
         return NSOrderedSame;
    else
         return NSOrderedDescending; }];

There's a pretty thorough discussion of sorting arrays, with examples, in the Collections Programming Topics document.

Check out: Obj/C: Sorting an array on a custom order

Upvotes: 2

cem
cem

Reputation: 3321

You can rearrange objects in an array by various sort methods, check the class reference for details.

Since

Upvotes: 0

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