Can't understand iPhone view layout

I have an iphone app that I built based off a tutorial (for a different framework so I had to modify things a bit) that uses a TabBar and a NavigationBar on the same View that also contains a UITable populated from an SQLite db. I built it last night and when you select an item in the UITable it was redirecting to a view that displayed the detail of my item (at that point, just a city name). I went in and tried to modify that DetailView...and nothing I change works. So I have a few questions/probl开发者_JAVA技巧ems: 1) Why is it that my CityDetailView.xib looks like this in Interface Builder:

alt text http://www.jamespwright.com/images/public/detailviewinterfacebuilder.jpg

But looks like this when the app is run:

alt text http://www.jamespwright.com/images/public/wrongdetailview.jpg

I am new to iPhone development, so I'm not even sure where to begin looking for this problem. I know that the TableViewController is set to CitiesTableViewController and within that controller code in my didSelectRowAtIndexPath I run this code:

MyAppDelegate *appDelegate = (MyAppDelegate *)[[UIApplication sharedApplication] delegate];
 City *city = (City *)[appDelegate.cities objectAtIndex:indexPath.row];

 // Initialize a new CityDetailView if there isn't one already
 if (self.cityView == nil) {
  CityDetailViewController *viewController = [[CityDetailViewController alloc] initWithNibName:@"CityDetailViewController" bundle:[NSBundle mainBundle]];

  self.cityView = viewController;
  [viewController release];
 }

 [appDelegate.citiesNavController pushViewController:cityView animated:YES];
 self.cityView.city = city;
 self.cityView.title = city.name;
 [self.cityView.cityName setText:city.name];
 [self.cityView.stateName setText:city.state];
 [self.cityView.population setText:city.population];

And I have the labels linked up in Interface Builder to the properties in the Controller. I also have the CityDetailView.xib class identity set to CityDetailViewController which has all the properties correctly declared. One thing I can't figure out, if I rename CityDetailView.xib to "CityDetailView.xib1" the program still runs the same, but if I change [self.cityView.title = city.name]; to [self.cityView.title = @"Bob's Your Uncle!"]; it displays that change within the program.

On a completely unrelated note, on my TableView (my 2nd tab) I have this odd bar at the bottom that I don't know what it is or how to get rid of it, I'm pretty sure it has to do with the NavigationController but I don't know why or how it's there. It is this one:

alt text http://www.jamespwright.com/images/public/tabandnavigationview.jpg

Can anyone offer me any advice on these problems?

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When "nothing happens" when you change source files, there are usually only a few things you're doing:

• Dates are screwed up somewhere and you need to clean (Build → Clean)
• You're editing the wrong file
• You're building the wrong target
• No, seriously, you're editing the wrong file, or building the wrong target

Cleaning is definitely the first thing to try. Especially if you can rename the XIB and everything still cheerfully goes on.

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The simplest explanation is that self.cityView.stateName and the subsequent labels are not hooked up in interface builder. The controller must have a hooked up outlet to each label in order to populate it. Objective-C won't raise an error if you send a message to an object it can't find.