Objective-c Sort Key array within array - iphone

Question

Assuming I have an NSMutableArray which is loaded from file:
searchTermsArray = [[NSMutableArray alloc] initWithContentsOfFile: yourArrayFileName];
inside this array items are key objects
for (int i=0; i<[searchTermsArray count]; i++) {
NSLog(#"for array item %d: %# - %#",i,[[searchTermsArray objectAtIndex:i] objectForKey:#"title"], [[searchTermsArray objectAtIndex:i] objectForKey:#"theCount"] );
}
(which means that each array element (item) has 2 keys values:
searchTermsArray[0] = title (string) , theCount (also a string, but made out of integers)
Question: how should I sort "searchTermsArray" array from higher to lower based on "theCount" value?
(I am looking at the following code but it is not fitting the structure/syntax)
NSSortDescriptor *Sorter = [[NSSortDescriptor alloc] initWithKey:#"title" ascending:NO];
[searchTermsArray sortUsingDescriptors:[NSArray arrayWithObject:Sorter]];
[Sorter release];

Answer 1

Shouldn't you be sorting based on theCount key?
NSSortDescriptor * descriptor = [NSSortDescriptor sortDescriptorWithKey:#"theCount" ascending:NO];
[searchTermsArray sortUsingDescriptors:[NSArray arrayWithObject:descriptor]];

Answer 2

I am not sure if there is a better way to do so. But this thing works.
NSInteger intSort(id param1, id param2, void *context) {
NSDictionary *dict1 = (NSDictionary *)param1;
NSDictionary *dict2 = (NSDictionary *)param2;
NSInteger dict1KeyCount = [[dict1 objectForKey:#"count"] intValue];
NSInteger dict2KeyCount = [[dict2 objectForKey:#"count"] intValue];
if (dict1KeyCount < dict2KeyCount) {
return NSOrderedAscending;
}else if (dict1KeyCount > dict2KeyCount) {
return NSOrderedDescending;
}else {
return NSOrderedSame;
}
}
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad {
NSMutableArray *array = [[NSMutableArray alloc] initWithObjects:[NSDictionary dictionaryWithObjectsAndKeys:#"two", #"title", #"2", #"count", nil],
[NSDictionary dictionaryWithObjectsAndKeys:#"three", #"title", #"3", #"count", nil],
[NSDictionary dictionaryWithObjectsAndKeys:#"one", #"title", #"1", #"count", nil], nil];
NSArray *sortedArray = [array sortedArrayUsingFunction:intSort context:NULL];
for (NSDictionary *dict in sortedArray) {
NSLog(#"%d", [[dict objectForKey:#"count"] intValue]);
}
[super viewDidLoad];
}

Answer 3

The NSSortDescriptor is usually used to sort objects of a class. You pass the name of the property in that class to be compared with others.
Since what you have in your array actually seems to be a NSDictionary, the NSSortDescriptor might not be the best way to approach this problem. Besides, your objects in the dictionary must have a type, so I would try to sort the array myself in one of the classic methods if I were you.