IOS 5 - 从另一个ViewController调用ViewController

Question

As I'm very new to IOS development, I don't really know all the mechanisms that are to be used while developing iPhone apps.

Here, what I'm trying to do is to call another controller after performing a segue.

The context :

I have my first page, which basically consists on a login page, with a user/password system. I created a segue which is called by clicking on the Submit button. Here's the code :

- (IBAction)Connect:(UIButton *)sender
{
    NSDictionary *dict = [NSDictionary dictionaryWithObjectsAndKeys:
                          @"passwordsample", @"usernamesample", 
                          nil];

    if ((![[dict allKeys] containsObject:TFLogin.text])) {
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Error" message:@"Login or password incorrect" delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil, nil];
        [alert show];
        NSLog(@"Connection Not OK");
    }
    else {
        [self performSegueWithIdentifier:@"LoginSegue" sender:sender];
        NSLog(@"Connection OK");
    }
}

And here's the prepareForSegue function :

- (void) prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    HomeController *home = (HomeController *) segue.destinationViewController;
    home.sentLogin = TFLogin.text;
}

The fact is that, when I click on the Submit button (on the login page), the logs show me that the user is correctly found, and then I get the error as following :

2012-04-30 11:24:44.630 AppName[1066:f803] -[UINavigationController setSentLogin:]: unrecognized selector sent to instance 0x6d73c30
2012-04-30 11:24:44.630 AppName[1066:f803] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UINavigationController setSentLogin:]: unrecognized selector sent to instance 0x6d73c30'

Here's the storyboard :

The second NavigationController is to be replaced with a Tab Bar Controller. But for some testing, I've put this one.

Could someone please guide me, telling me what I'm doing wrong and/or sending me some recent guides on storyboarding and navigation ?

Thanks a lot !

Answer 1

By the looks of the error, it seems like segue.destinationViewController isn't what you think it is. Sounds like you have a navigation controller in the mix.

It's a bit difficult to diagnose without your storyboard but try:

UINavigationController *nav = (UINavigationController*)segue.destinationViewController;
HomeController *home = (HomeController*)nav.topViewController;

If that doesn't work, you may want to place a breakpoint on the second line and take a look at the nab controller to see where the HomeController is on its stack.

Answer 2

ProjectManagementViewController * projectManagementView = [[ProjectManagementViewController alloc] initWithNibName：@“ProjectManagementViewController”bundle：nil];

 [self.navigationController pushViewController:projectManagementView animated:NO];

Answer 3

you can do it like in ios5:

[self performSegueWithIdentifier:@"your-segue-name" sender:self];

you will create a segue from one of your view to another but not through buttons or anything else , just drag from your first-view to second-view your segue and when your process done just call the code above.

hope this helps..

edit : you need to give a name to your segue in your storyboard just clicking on it and then naming in on the right-side inspector..