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Help with looping through array in a loop

I am trying to get a list of numbers from the address book. I am then trying to get all users from parse.com that match the numbers found in the address book. In other words, I am trying to pull down all the users that someone would know / has stored in their address book ... using the mobile as the identifier.

I have it half working, but it appears to loop over and over until all checked and I end up with only 1 result in my view.

If anyone is able to help me re-factor how I am supposed to combine these things and alter my query or indeed offer best practice I would be most appreciative :)

    // load up all the numbers for the user

    CFErrorRef *error = NULL;
    ABAddressBookRef addressBook = ABAddressBookCreateWithOptions(NULL, error);
    CFArrayRef allPeople = ABAddressBookCopyArrayOfAllPeople(addressBook);
    CFIndex numberOfPeople = ABAddressBookGetPersonCount(addressBook);

    for(int i = 0; i < numberOfPeople; i++) {

        ABRecordRef person = CFArrayGetValueAtIndex( allPeople, i );

        //NSString *firstName = (__bridge NSString *)(ABRecordCopyValue(person, kABPersonFirstNameProperty));
        //NSString *lastName = (__bridge NSString *)(ABRecordCopyValue(person, kABPersonLastNameProperty));
        //NSLog(@"Name:%@ %@", firstName, lastName);

        ABMultiValueRef phoneNumbers = ABRecordCopyValue(person, kABPersonPhoneProperty);

        for (CFIndex i = 0; i < ABMultiValueGetCount(phoneNumbers); i++) {
            NSString *phoneNumber = (__bridge_transfer NSString *) ABMultiValueCopyValueAtIndex(phoneNumbers, i);

    NSLog(@"the number%@", phoneNumber);

    PFQuery *query = [PFUser query];
    [query whereKey:@"mobile" equalTo:phoneNumber];
    [query orderByAscending:@"username"];
    [query findObjectsInBackgroundWithBlock:^(NSArray *objects, NSError *error) {

        if (error) {
            NSLog(@"Error: %@ %@", error, [error userInfo]);

        else {

            self.allUsers = objects;
            [self.tableView reloadData];



    self.currentUser =[PFUser currentUser];



1 Answer

Amit Bijlani
Amit Bijlani
Treehouse Guest Teacher

Why not try the following:

  1. Build an array of phone numbers, let's call it phoneNumbers.
  2. Download a list of all users from Parse, let's call it users.
  3. Loop through all the users and create a new array called friends. Only add objects to the friends if their phone number exists in the phoneNumbers array using the containsObject method.