NavigationBarに閉じるボタンを置く

gistfile1.m

UIBarButtonItem *closeButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"閉じる"
                                                                    style:UIBarButtonItemStyleBordered
                                                                   target:self
                                                                   action:@selector(close:)];
self.navigationItem.leftBarButtonItem = closeButtonItem;
[closeButtonItem release];