UIAlertController: style alert

-(void)mostrarAviso {
    
    UIAlertController * alert=   [UIAlertController
                                  alertControllerWithTitle:NSLocalizedString(@"Título", nil)
                                  message:NSLocalizedString(@"Mensaje", nil)
                                  preferredStyle:UIAlertControllerStyleAlert];
    
    UIAlertAction* okButton = [UIAlertAction
                                actionWithTitle:NSLocalizedString(@"Ok", nil)
                                style:UIAlertActionStyleDefault
                                handler:^(UIAlertAction * action)
                                {
                                    
                                    [alert dismissViewControllerAnimated:YES completion:nil];
                                    
                                }];
    [alert addAction:okButton];
    
    [self presentViewController:alert animated:YES completion:nil];
    
}

Compartir texto

-(void) compartirTexto: (NSString *) textoAEnviar {
    
    UIActivityViewController *activityViewController =
    [[UIActivityViewController alloc] initWithActivityItems:@[textoAEnviar]
                                      applicationActivities:nil];
    [self.navigationController presentViewController:activityViewController
                                       animated:YES
                                     completion:^{
                                         
                                     }];
    
}

Petición JSON mediante AFHTTPSessionManager

NSArray *campos = [NSArray arrayWithObjects:@"dato001",@"dato002", nil];
    NSArray *valores = [NSArray arrayWithObjects:dato001,dato002, nil];
    NSDictionary *diccionario = [NSDictionary dictionaryWithObjects:valores forKeys:campos];
    
    AFHTTPSessionManager *manager = [AFHTTPSessionManager manager];

    manager.responseSerializer = [AFJSONResponseSerializer serializer];
    manager.responseSerializer = [AFHTTPResponseSerializer serializer];
    
    [manager POST:URL_PETICION parameters:diccionario progress:nil success:^(NSURLSessionTask *task, id responseObject) {
        
        NSDictionary* json = [NSJSONSerialization
                              JSONObjectWithData:responseObject
                              options:kNilOptions
                              error:nil];
        
        if ([[json objectForKey:@"success"] intValue] == 1) {
            
        }
    
    } failure:^(NSURLSessionTask *operation, NSError *error) {
        
        NSLog(@"Error: %@", error.localizedDescription );
        
        NSMutableString *mensaje = [[NSMutableString alloc] init];
        [mensaje appendString:NSLocalizedString(@"Fallo en la conexión", nil)];
        
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:NSLocalizedString(@"Información",nil) message:mensaje delegate:self cancelButtonTitle:@"Ok" otherButtonTitles:nil, nil];
        [alert show];
        
    }];

Altura dinámica de celdas en UITableView

//Capturamos la celda
        static NSString *identificadorCelda = @"CeldaListado";
        
        celdaListado *cell = [tableView dequeueReusableCellWithIdentifier:identificadorCelda];
        //Creamos una label donde alojamos el texto y calculamos su altura
        UILabel *gettingSizeLabel = [[UILabel alloc] init];
        gettingSizeLabel.font = cell.aviso.font;
        Modelo *modelo = [listado objectAtIndex:indexPath.row];
        gettingSizeLabel.text = modelo.descripcion_aviso;
        gettingSizeLabel.numberOfLines = 0;
        gettingSizeLabel.lineBreakMode = NSLineBreakByWordWrapping;
        CGSize maximumLabelSize = CGSizeMake(cell.modelo.frame.size.width, 9999);
        CGSize expectSize = [gettingSizeLabel sizeThatFits:maximumLabelSize];
        
        //Tomamos la medida total de la celda
        CGRect cellFrame = cell.frame;
        //Sumamos la altura de la label a la celda
        return cellFrame.size.height+expectSize.height - 5;