UITableViewCell doesn't display - ios

Question

I have a problem with my TableViewController. There is a custom cell, with a class, and various infos dynamically loaded. My TableViewController appears, but my cell doesn't display, but i can touch this, and my transition with infos are good.
Thanks for your answers.
TableViewController.m
#interface Chat() {
NSMutableArray *messages;
UIRefreshControl *refreshControl;
}
#property (strong, nonatomic) IBOutlet UITableView *tableMessages;
#end
#implementation Chat
NSString *cellIdentifier = #"ChatCell";
- (void)viewDidLoad {
[super viewDidLoad];
[_tableMessages registerClass:[ChatCell class] forCellReuseIdentifier:cellIdentifier];
refreshControl = [[UIRefreshControl alloc] init];
[refreshControl addTarget:self action:#selector(loadMessages) forControlEvents:UIControlEventValueChanged];
[_tableMessages addSubview:refreshControl];
messages = [[NSMutableArray alloc] init];
[self loadMessages];
}
- (void)loadMessages {
if ([PFUser currentUser] != nil)
{
PFQuery *query = [PFQuery queryWithClassName:PF_MESSAGES_CLASS_NAME];
[query whereKey:PF_MESSAGES_USER equalTo:[PFUser currentUser]];
[query includeKey:PF_MESSAGES_LASTUSER];
[query orderByDescending:PF_MESSAGES_UPDATEDACTION];
[query findObjectsInBackgroundWithBlock:^(NSArray *objects, NSError *error) {
if (error == nil) {
[messages removeAllObjects];
[messages addObjectsFromArray:objects];
[_tableMessages reloadData];
} else [ProgressHUD showError:#"Network error."];
[refreshControl endRefreshing];
}];
}
}
- (void)actionCleanup {
[messages removeAllObjects];
[_tableMessages reloadData];
}
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return [messages count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
ChatCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier forIndexPath:indexPath];
[cell bindData:messages[indexPath.row]];
return cell;
}
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath {
return YES;
}
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {
DeleteMessageItem(messages[indexPath.row]);
[messages removeObjectAtIndex:indexPath.row];
[_tableMessages deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
}
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
[tableView deselectRowAtIndexPath:indexPath animated:YES];
PFObject *message = messages[indexPath.row];
ChatView *chatView = [[ChatView alloc] initWith:message[PF_MESSAGES_ROOMID]];
[self.navigationController pushViewController:chatView animated:YES];
}
#end
TableViewCell.m
#interface ChatCell() {
PFObject *message;
}
#end
#implementation ChatCell
- (void)bindData:(PFObject *)message_ {
message = message_;
_chatImg.layer.cornerRadius = _chatImg.frame.size.width/2;
_chatImg.layer.masksToBounds = YES;
PFUser *lastUser = message[PF_MESSAGES_LASTUSER];
[_chatImg setFile:lastUser[PF_USER_PICTURE]];
[_chatImg loadInBackground];
_chatUsername.text = message[PF_MESSAGES_DESCRIPTION];
_chatMessage.text = message[PF_MESSAGES_LASTMESSAGE];
NSTimeInterval seconds = [[NSDate date] timeIntervalSinceDate:message.updatedAt];
_chatDate.text = TimeElapsed(seconds);
}
#end

Answer 1

It's because you register the cell using - registerClass:forCellReuseIdentifier:.
If you register it this way you have to construct the view programmatically or load the nib file in ChatCell code.
To solve the problem, do either of these:
Create a nib file containing the view for your table view cell and set the class to ChatCell. Then use - registerNib:forCellReuseIdentifier: to register the nib.
Construct the view programmatically eg. create a UILabel and add it as a subview of ChatCell.
Make the prototype cell in the storyboard and set the cell identifier to ChatCell. Then remove the - registerClass:forCellReuseIdentifier:

Answer 2

Check You are given correct cell Identifier in storyboard. (case sensitive) " ChatCell"
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *cellIdentifier = #"ChatCell";
ChatCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier forIndexPath:indexPath];
[cell bindData:messages[indexPath.row]];
return cell;
}

Answer 3

You are updating the UI on background thread. Try this, in your "loadMessages" method.
[query findObjectsInBackgroundWithBlock:^(NSArray *objects, NSError *error) {
dispatch_async(dispatch_get_main_queue(), ^{
//update UI here
if (error == nil) {
[messages removeAllObjects];
[messages addObjectsFromArray:objects];
[_tableMessages reloadData];
} else [ProgressHUD showError:#"Network error."];
[refreshControl endRefreshing];
});
}];