How to pop up from one UIviewController to another uiviewcontroller

[rk_mail04]

In Navigation based application, i am getting problem for accesing one TableView UIViewController to another UIViewController.

NextViewController.h //Edit

IBOutlet UILabel *lblProductTxt;

     NextViewController.m  

        - (IBAction) changeProductText:(NSString *)str{
            lblProductTxt.text = str;
        }

            Symptoms.m

                 - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath 
                {
                 NextViewController *nextController = [[NextViewController alloc] initWithNibName:@"NextViewController" bundle:nil];

                 [self.navigationController pushViewController:nextController animated:YES];

             

                 if(indexPath.section == 0)
                 {
                  [nextController changeProductText:[Test1 objectAtIndex:indexPath.row]];
                 }

                 if(indexPath.section == 1)
                 {
                  [nextController changeProductText:[Test2 objectAtIndex:indexPath.row]];
                 }

                 if(indexPath.section == 2)
                 {

                  [nextController changeProductText:[Notes objectAtIndex:indexPath.row]];
                 }

                 [nextController release];

                }

I am getting dates corresponding SymptomviewController UITable Row . when i tap on row date is not going to nextviewcontroller window . How to pop up nextviewcontroller