Array reduplication not working - objective-c

Question

Xcode problem. I have a nsmutablearray that is pulling json objects. Example Company: Name, state, address, phone number, etc.
I am pulling the info just fine. And I want to display 1 of each state in a table view. It works fine but shows multibles of the same state. But I only want to show 1 of each state. I am using some code but it does not return any states. I have seen a lot of examples and this should work but it returns nothing. If I skip this code below it does show all states. i have also tried a for loop. And tried array to NSSet. Nothing is working. Any Ideas???
My problem is with this code...
//Create states only array...remove duplicate states here
NSArray *statesArray = [companies valueForKeyPath:#"#distinctUnionOfObjects.state"];
return statesArray;
Here is my whole code. Please help been struggling with this for a week.
#interface StatesTableViewController ()
#property (nonatomic) NSString *name;
#property (nonatomic) NSString *state;
#end
#implementation StatesTableViewController
NSArray *companies;
NSArray *statesArray;
- (void)viewDidLoad {
[super viewDidLoad];
NSString *address = #"http://www.companiesFeed";
NSURL *url = [[NSURL alloc] initWithString:address];
//laod the data on a background queue..
//if we were connecting to a an online url then we need it
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
companies = [self readCompanies:url];//, statesSet = [self readCompanies:url];
//now that we have the data, reload the table data on the main ui thread
[self.tableView performSelectorOnMainThread:#selector(reloadData) withObject:nil waitUntilDone:YES];
});
}
//new code
- (NSArray *)readCompanies:(NSURL *)url {
//create a nsurlrequest with the given Url
NSURLRequest *request = [NSURLRequest requestWithURL:url cachePolicy:
NSURLRequestReloadIgnoringLocalAndRemoteCacheData timeoutInterval:30.0];
//get the data
NSURLResponse *response;
NSData *data = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:nil];
//now create a nsdictionary from the json data
NSDictionary *jsonDictionary = [NSJSONSerialization JSONObjectWithData:data
options:0 error:nil];
//create a new array to hold the comanies
NSMutableArray *companies = [[NSMutableArray alloc] init];
//get an array of dictionaries with the key "company"
NSArray *array = [jsonDictionary objectForKey:#"companies"];
//iterate throught the array of dictionaries
for (NSDictionary *dict in array) {
//create a new company object with information in the dictionary
Company *company = [[Company alloc] initWithJSONDictionary:dict];
//add the Company object to the array
[companies addObject:company ];
}
//Create states only array...remove duplicate states here
NSArray *statesArray = [companies valueForKeyPath:#"#distinctUnionOfObjects.state"];
return statesArray;
//return companies;
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#pragma mark -table view controller methods
//change uniqueValue errors to companies
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger) section {
//return[companies count];
return [statesArray count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *cellID = #"CellIDState";
UITableViewCell *cell = [self.tableView dequeueReusableCellWithIdentifier:cellID];
if (cell == nil){
//single line on table view
//cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleValue1 reuseIdentifier:cellID];
// dual line on table view
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:cellID];
}
//edit single state
//Company *company = [companies objectAtIndex:indexPath.row];
Company *company = [statesArray objectAtIndex:indexPath.row];
//cell.textLabel.text = company.company_id;
cell.textLabel.text = company.state;
cell.detailTextLabel.text = [NSString stringWithFormat:#"%#",company.companyName];
//adds cheveron to tableviewl
[cell setAccessoryType: UITableViewCellAccessoryDisclosureIndicator];
return cell;
}
#pragma mark - navigation
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender{
}
#end

Answer 1

I was able to get the unique list of states by using a predicate and a block to check a set for existing states. Like so:
NSMutableArray *statesArray = [NSMutableArray array];
[companies filteredArrayUsingPredicate:[NSPredicate predicateWithBlock:^BOOL(id evaluatedObject, NSDictionary *bindings) {
Company *dict = (Company *)evaluatedObject;
BOOL seen = [statesArray containsObject:dict];
if (!seen) {
[statesArray addObject:dict];
}
return !seen;
}]];
NSLog(#"unique states: %#", statesArray);
Where the companies array looks like this:
{[{
"company_id": "22",
"entityformSubmissionID": "22",
"companyName": "house of waffles",
"companySlogan": " where your home is!",
"address1": "123 here",
"address2": "thre",
"city": "everywhere",
"state": "CA",
"zipCode": "94531",
"phoneNumber": "777-777-7777",
"email": "test#test.com",
"additionalCompanyInfo": "all additional company info is going here",
"sales": "There are no sales!",
"rentalTerms": "Terms is dont break our stuff jerks!",
"companyLogo": "/16x16icon.png"
}]