StackOverflow2013

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POHow to add dynamically rows to a UITableView in iOS?
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copied!<p>I'm developing a view controller for a chat application and I want to show a UIViewController that contains a UITableView (where messages are shown with different format [if is your message or if is a message from other person], a UITextField (to write your messages) and a UIButton (to send the message)</p> <p>I'm using SRWebSocket example but they use a UITableViewController (that runs perfectly but don't allow me to modify tableview size or to add the others components to the view by storyboard)</p> <p>This is the code that I have in my Controller:</p> <h2>ChatViewController.h</h2> <pre><code>#import <UIKit/UIKit.h> #import "SRWebSocket.h" #import "ChatCell.h" #import "Message.h" #import "Person.h" #import "Program.h" #import "DateFactory.h" @interface ChatViewController : UIViewController <UITableViewDataSource,UITableViewDelegate,SRWebSocketDelegate, UITextViewDelegate, UITextFieldDelegate> @property (strong, nonatomic) NSDictionary *programSegue; @property (retain, nonatomic) IBOutlet UITableView *tableView; @property (nonatomic, retain) IBOutlet UITextView *inputView; - (IBAction)goingUp:(id)sender; @property (weak, nonatomic) IBOutlet UITextField *inputText; @end </code></pre> <h2>ChatViewController.m</h2> <h3>Code that fails:</h3> <pre><code>[self.tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:[NSIndexPath indexPathForRow:_messages.count - 1 inSection:0]] withRowAnimation:UITableViewRowAnimationNone]; </code></pre> <p>in:</p> <pre><code>- (void)webSocket:(SRWebSocket *)webSocket didReceiveMessage:(id)message; { NSLog(@"Received \"%@\"", message); NSError *e; NSDictionary *allJSON = [NSJSONSerialization JSONObjectWithData: [message dataUsingEncoding:NSUTF8StringEncoding] options: NSJSONReadingMutableContainers error: &e]; NSString *kindJSON = [allJSON objectForKey:@"kind"]; NSString *userJSON = [allJSON objectForKey:@"user"]; NSString *messageJSON = [allJSON objectForKey:@"message"]; NSArray *membersJSON = [allJSON objectForKey:@"members"]; DateFactory *dateFactory = [DateFactory alloc]; NSString *formatDate = @"dd/MM/YYYY HH:mm"; NSString *dateString = [dateFactory dateToString:[NSDate date] withFormat:formatDate]; switch([@[@"join", @"talk", @"quit"] indexOfObject:kindJSON]){ // join case 0: break; // talk case 1: [_messages addObject:[[Message alloc] initWithMessage:messageJSON fromMe:NO]]; [self.tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:[NSIndexPath indexPathForRow:_messages.count - 1 inSection:0]] withRowAnimation:UITableViewRowAnimationNone]; [self.tableView scrollRectToVisible:self.tableView.tableFooterView.frame animated:YES]; break; // quit case 2: [[self.navigationItem.titleView.subviews objectAtIndex:1] setText: [NSString stringWithFormat:@"Sin conexión desde %@", dateString]]; break; } } </code></pre> <p>ERROR</p> <pre><code>Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'attempt to insert row 0 into section 0, but there are only 0 rows in section 0 after the update' </code></pre> <h3>Full code:</h3> <pre><code>#import "ChatViewController.h" @interface ChatViewController () @end @implementation ChatViewController{ SRWebSocket *_webSocket; NSMutableArray *_messages; Person *person; Program *program; } @synthesize programSegue; @synthesize tableView; @synthesize inputText; @synthesize inputView = _inputView; - (BOOL)textFieldShouldReturn:(UITextField *)textField { return [inputText resignFirstResponder]; } #pragma mark - View lifecycle - (void)viewDidLoad; { [super viewDidLoad]; [inputText setDelegate:self]; person = [programSegue objectForKey:@"PERSON"]; program = [programSegue objectForKey:@"PROGRAM"]; self.navigationItem.title = person.name; // Creates picture to be shown in navigation bar UIButton* picture = (UIButton *) [[UIImageView alloc] initWithImage:[UIImage imageNamed:person.imageURL]]; CGRect buttonFrame = picture.frame; buttonFrame.size = CGSizeMake(38, 38); picture.frame = buttonFrame; UIBarButtonItem *pictureItem = [[UIBarButtonItem alloc] initWithCustomView:picture]; self.navigationItem.rightBarButtonItem = pictureItem; // Set title and subtitle CGRect frame = self.navigationController.navigationBar.frame; UIView *twoLineTitleView = [[UIView alloc] initWithFrame:CGRectMake(CGRectGetWidth(frame), 0, CGRectGetWidth(frame), CGRectGetHeight(frame))]; UILabel *titleLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 6, CGRectGetWidth(frame), 20)]; titleLabel.backgroundColor = [UIColor clearColor]; [titleLabel setTextColor:[UIColor whiteColor]]; titleLabel.autoresizingMask = UIViewAutoresizingFlexibleWidth; [titleLabel setTextAlignment:NSTextAlignmentCenter]; [titleLabel setFont:[UIFont boldSystemFontOfSize:16]]; [titleLabel setShadowColor:[UIColor grayColor]]; titleLabel.text = person.name; [twoLineTitleView addSubview:titleLabel]; UILabel *subTitleLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 26, CGRectGetWidth(frame), 14)]; subTitleLabel.backgroundColor = [UIColor clearColor]; [subTitleLabel setTextColor:[UIColor whiteColor]]; subTitleLabel.autoresizingMask = UIViewAutoresizingFlexibleWidth; [subTitleLabel setTextAlignment:NSTextAlignmentCenter]; [subTitleLabel setFont:[UIFont boldSystemFontOfSize:12]]; [titleLabel setShadowColor:[UIColor grayColor]]; subTitleLabel.text = @"subtitleg"; [twoLineTitleView addSubview:subTitleLabel]; self.navigationItem.titleView = twoLineTitleView; // Start messages _messages = [[NSMutableArray alloc] init]; [self.tableView reloadData]; } - (void)_reconnect; { _webSocket.delegate = nil; [_webSocket close]; _webSocket = [[SRWebSocket alloc] initWithURLRequest: [NSURLRequest requestWithURL: [NSURL URLWithString: [NSString stringWithFormat:@"ws://81.45.19.228:8000/room/chat?username=enrimr&amp;pid=%@", person.name]]]]; _webSocket.delegate = self; //self.title = @"Opening Connection..."; [[self.navigationItem.titleView.subviews objectAtIndex:1] setText:@"Conectando..."]; [_webSocket open]; } - (void)viewWillAppear:(BOOL)animated { [super viewWillAppear:animated]; [self _reconnect]; } - (void)reconnect:(id)sender; { [self _reconnect]; } - (void)viewDidAppear:(BOOL)animated; { [super viewDidAppear:animated]; [_inputView becomeFirstResponder]; [self.tableView scrollRectToVisible:self.tableView.tableFooterView.frame animated:YES]; } - (void)viewDidDisappear:(BOOL)animated { [super viewDidDisappear:animated]; _webSocket.delegate = nil; [_webSocket close]; _webSocket = nil; } #pragma mark - UITableViewController - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section; { return _messages.count; } - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView{ return 1; } - (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath; { ChatCell *chatCell = (id)cell; Message *message = [_messages objectAtIndex:indexPath.row]; chatCell.text.text = message.message; chatCell.date.text = message.fromMe ? @"Me" : @"Other"; } - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath; { Message *message = [_messages objectAtIndex:indexPath.row]; ChatCell *cell = (ChatCell *)[self.tableView dequeueReusableCellWithIdentifier:@"programCell" forIndexPath:indexPath]; if (!cell) { if (message.fromMe){ cell = [[ChatCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"SentCell"]; [cell.text setText:message.message]; [cell.date setText:@"00:00"]; } else { cell = [[ChatCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"ReceivedCell"]; [cell.text setText:message.message]; [cell.date setText:@"00:00"]; } } return cell; } #pragma mark - SRWebSocketDelegate - (void)webSocketDidOpen:(SRWebSocket *)webSocket; { NSLog(@"Websocket Connected"); //self.title = @"Connected!"; [[self.navigationItem.titleView.subviews objectAtIndex:1] setText:@"Conectado"]; } - (void)webSocket:(SRWebSocket *)webSocket didFailWithError:(NSError *)error; { NSLog(@":( Websocket Failed With Error %@", error); self.title = @"Connection Failed! (see logs)"; _webSocket = nil; } - (void)webSocket:(SRWebSocket *)webSocket didReceiveMessage:(id)message; { NSLog(@"Received \"%@\"", message); NSError *e; NSDictionary *allJSON = [NSJSONSerialization JSONObjectWithData: [message dataUsingEncoding:NSUTF8StringEncoding] options: NSJSONReadingMutableContainers error: &e]; NSString *kindJSON = [allJSON objectForKey:@"kind"]; NSString *userJSON = [allJSON objectForKey:@"user"]; NSString *messageJSON = [allJSON objectForKey:@"message"]; NSArray *membersJSON = [allJSON objectForKey:@"members"]; DateFactory *dateFactory = [DateFactory alloc]; NSString *formatDate = @"dd/MM/YYYY HH:mm"; NSString *dateString = [dateFactory dateToString:[NSDate date] withFormat:formatDate]; switch([@[@"join", @"talk", @"quit"] indexOfObject:kindJSON]){ // join case 0: break; // talk case 1: [_messages addObject:[[Message alloc] initWithMessage:messageJSON fromMe:NO]]; [self.tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:[NSIndexPath indexPathForRow:_messages.count - 1 inSection:0]] withRowAnimation:UITableViewRowAnimationNone]; [self.tableView scrollRectToVisible:self.tableView.tableFooterView.frame animated:YES]; break; // quit case 2: [[self.navigationItem.titleView.subviews objectAtIndex:1] setText: [NSString stringWithFormat:@"Sin conexión desde %@", dateString]]; break; } } - (void)webSocket:(SRWebSocket *)webSocket didCloseWithCode:(NSInteger)code reason:(NSString *)reason wasClean:(BOOL)wasClean; { NSLog(@"WebSocket closed"); //self.title = @"Connection Closed! (see logs)"; [[self.navigationItem.titleView.subviews objectAtIndex:1] setText:@"Offline"]; _webSocket = nil; } - (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text; { if ([text rangeOfString:@"\n"].location != NSNotFound) { NSString *message = [[textView.text stringByReplacingCharactersInRange:range withString:text] stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]]; [_webSocket send:message]; [_messages addObject:[[Message alloc] initWithMessage:message fromMe:YES]]; [self.tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:[NSIndexPath indexPathForRow:_messages.count - 1 inSection:0]] withRowAnimation:UITableViewRowAnimationNone]; [self.tableView scrollRectToVisible:self.tableView.tableFooterView.frame animated:YES]; textView.text = @""; return NO; } return YES; } - (void) animateTextField: (UITextField*) textField up: (BOOL)up { const int movementDistance = 218; const float movementDuration = 0.3f; int movement = (up ? -movementDistance : movementDistance); [UIView beginAnimations: @"anim" context: nil]; [UIView setAnimationBeginsFromCurrentState: YES]; [UIView setAnimationDuration: movementDuration]; self.view.frame = CGRectOffset(self.view.frame, 0, movement); [UIView commitAnimations]; } - (IBAction)goingUp:(id)sender { [self animateTextField:inputText up:TRUE]; } @end </code></pre>

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