Question

Let i have unsorted NSMutableDictionary

    {
        A = "3";
        B = "2"; 
        C = "4";
    }

And i need result to be like:

    {
        B = "2";
        A = "3";
        C = "4";
    }

How can i achieve this result in objective c.

A simple code implementation will be appreciated.

Answer 1

You can not sort NSMutableDictionary by value as @joe and @mavrick3 answer. However if you change there keys and values to NSArray you can do it..
Here is simple implementation..
NSMutableDictionary *results; //dictionary to be sorted

    NSMutableDictionary *results; //dict to be sorted
    NSArray *sortedKeys = [results keysSortedByValueUsingComparator: ^(id obj1, id obj2) {
        if ([obj1 integerValue] > [obj2 integerValue]) 
            return (NSComparisonResult)NSOrderedDescending;
        if ([obj1 integerValue] < [obj2 integerValue])
            return (NSComparisonResult)NSOrderedAscending; 
        return (NSComparisonResult)NSOrderedSame;
    }];
    NSArray *sortedValues = [[results allValues] sortedArrayUsingSelector:@selector(compare:)];

    //Descending order
    for (int s = ([sortedValues count]-1); s >= 0; s--) {
        NSLog(@" %@ = %@",[sortedKeys objectAtIndex:s],[sortedValues objectAtIndex:s]); 
    }
    //Ascending order
    for (int s = 0; s < [sortedValues count]; s++) {
        NSLog(@" %@ = %@",[sortedKeys objectAtIndex:s],[sortedValues objectAtIndex:s]); 
    }