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iOS

Posted by Elizabeth Hill
Elizabeth Hill
1,147 Points

friends in the Ribbit App

So I am stuck on http://teamtreehouse.com/library/build-a-selfdestructing-message-iphone-app-2/relating-users-in-parsecom/adding-checkmarks-when-the-table-view-is-loaded-2

The friends are listed in the edit friends view controller but NOT in the friends view controller. I don't understand what I am doing wrong. Not even the CHECKMARKS are showing up in the edit friends view controller. I also don't like the idea of LOOPING through users. Is there any hashing or caching methods I could use so the app won't crash?

here is my code :

friends view controller.h

#import <UIKit/UIKit.h> #import <Parse/Parse.h> @interface friendsViewController : UITableViewController

@property (nonatomic, strong) PFRelation *friendsRelation; @property (nonatomic, strong) NSArray *friends;

```friends view controller.m```

#import "friendsViewController.h"
#import "GravatarUrlBuilder.h"
#import "EditfriendsViewController.h"

@interface friendsViewController ()

@end

@implementation friendsViewController

- (void)viewDidLoad
{
    [super viewDidLoad];

}

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];

    self.friendsRelation = [[PFUser currentUser] objectForKey:@"friendsRelation"];

    PFQuery *query = [self.friendsRelation query];
    [query orderByAscending:@"username"];
    [query findObjectsInBackgroundWithBlock:^(NSArray *objects, NSError *error) {
        if (error) {
            NSLog(@"Error %@ %@", error, [error userInfo]);
        }
        else {
            self.friends = objects;
            [self.tableView reloadData];

        }

    }];


}
//APP CRASH VIDEO
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    if ([segue.identifier isEqualToString:@"showEditFriends"]) {
        EditfriendsViewController *viewController = (EditfriendsViewController *)segue.destinationViewController;
        viewController.friends = [NSMutableArray arrayWithArray:self.friends];


    }
}

#pragma mark - Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{

    // Return the number of sections.
    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{

    // Return the number of rows in the section.
    return [self.friends count];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];

    PFUser *user = [self.friends objectAtIndex:indexPath.row];
    cell.textLabel.text = user.username;

    dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);

    dispatch_async(queue, ^{
        //get email address
        NSString *email = [user relationForKey:@"email"];

        //create md5 hash
        NSURL *gravatarUrl = [GravatarUrlBuilder getGravatarUrl:email];

        //request image from gravatar
        NSData *imageData = [NSData dataWithContentsOfURL:gravatarUrl];

        dispatch_async(dispatch_get_main_queue(), ^{ //set image in cell
            cell.imageView.image = [UIImage imageWithData:imageData];
            [cell setNeedsLayout];
     });

    });



    return cell;
}



@end




edit friends view controller.h

#import <UIKit/UIKit.h>
#import <Parse/Parse.h>

@interface EditfriendsViewController : UITableViewController

@property (nonatomic, strong) NSArray *allUsers;
@property (nonatomic, strong) PFUser *currentUser;
@property (nonatomic, strong) NSMutableArray *friends;


- (BOOL)isFriend:(PFUser *)user;

@end

edit friends view controller.m

#import "EditfriendsViewController.h"


@interface EditfriendsViewController ()

@end

@implementation EditfriendsViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    PFQuery *query = [PFUser query];
    [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];


}

#pragma mark - Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{

    // Return the number of sections.
    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{

    // Return the number of rows in the section.
    return [self.allUsers count];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];

    PFUser *user = [self.allUsers objectAtIndex:indexPath.row];
    cell.textLabel.text = user.username;


    //APP CRASH through looping
    if ([self isFriend:user]) {
        //add checkmark
        cell.accessoryType = UITableViewCellAccessoryCheckmark;

    }
    else {
        //clear checkmark
        cell.accessoryType = UITableViewCellAccessoryNone;
    }

    return cell;
}

#pragma mark - Table view delegate

- (void)tableView:(UITableView *)tableView accessoryButtonTappedForRowWithIndexPath:(NSIndexPath *)indexPath {
    [self.tableView deselectRowAtIndexPath:indexPath animated:NO];


    UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
    cell.accessoryType = UITableViewCellAccessoryCheckmark;
    PFRelation *friendsRelation = [self.currentUser relationForKey:@"friendsRelation"];
    PFUser *user = [self.allUsers objectAtIndex:indexPath.row];

    if ([self isFriend:user]) {
        cell.accessoryView = nil;

        for(PFUser *friend in self.friends) {
            if ([friend.objectId isEqualToString:user.objectId]) {
                [self.friends removeObject:friend];
                break;
            }
        }
        [friendsRelation removeObject:user];
    }
         else {
             cell.accessoryView = UITableViewCellAccessoryNone;
             [self.friends addObject:user];
             [friendsRelation addObject:user];
         }
         [self.currentUser saveInBackgroundWithBlock:^(BOOL succeeded, NSError *error) {
        if (error) {
            NSLog(@"Error: %@ %@", error, [error userInfo]);
        }
    }];
         }


#pragma mark - Helper methods


//app will crash while looping
- (BOOL)isFriend:(PFUser *)user {
    for (PFUser *friend in self.friends) {
        if ([friend.objectId isEqualToString:user.objectId]) {
            return YES;
        }
    }

    return NO;

}

@end