Question

I am actually trying to display a new controller of type UIViewController MKMapViewDelegate
in the function didSelectRowAtIndexPath.
I have a tableview in a controller and when I click on a cell of this tableview i want to display the new controller of type UIViewController MKMapViewDelegate.

My code is the following:

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath     *)indexPath
{
// Navigation logic may go here. Create and push another view controller.
UIViewController *mapviewtest=[[MapStation alloc]initWithNibName:@"MapStation"   bundle:nil];
[self.navigationController pushViewController:mapviewtest animated:YES];

//Station *station = nil;
//station = [self.listStation objectAtIndex:indexPath.row];
}

The problem is when i click on any cell of the tableview the program quit with a breakpoint on the line:

UIViewController *mapviewtest=[[MapStation alloc]initWithNibName:@"MapStation"   bundle:nil];

I don’t know why it does that and how to resolve this mistake. Maybe do you know an other way to do it(without using pushviewController function).

Waiting for your answers guys 😉

Sincerely

Quentin

Answer 1

It sounds like you need to change the way you set up the application a little. Follow the design below and you should be fine. Your major problem sounds like you are not creating a navigation controller which you must do.

Inside the App Delegate:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    // Create the Window
    self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];

    // Create RootViewController (i.e. Table View)
    RootViewController *rootViewController = [[RootViewController alloc] initWithNibName:@"RootViewController" bundle:nil];

    // Create the Navigation Controller
    UINavigationController *navigationController = [[UINavigationController alloc] initWithRootViewController:rootViewController];

    // Make the Navigation Controller the RootViewController
    self.window.rootViewController = navigationController;

    // Display the Window
    [self.window makeKeyAndVisible];

    return YES;
}

Inside the RootViewController:

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    // Create MapStation
    MapStation *mapviewtest = [[MapStation alloc] initWithNibName:@"MapStation" bundle:nil];

    // Push MapStation on to the self.navigationController (i.e you in the RootViewController class right
    // which is a navigation controller so this will work.
    [self.navigationController pushViewController:mapviewtest animated:YES];

    // mapviewtest is retained by the navigationController so release it
    [mapviewtest release];
}