將backBarButtonItem添加到沒有UINavigationController的navigationItem？

Question

我有一個UIViewController，並且我在InterfaceBuilder中添加了一個navigationItem來查看標題，我發現我不能將一個backBarButtonItem拖動到navigationItem，只能添加leftBarButtonItem和rightBarButtonItem。所以我儘量backBarButtonItem在我的控制器代碼添加到navigationItem元素：

- (void)viewWillAppear:(BOOL)animated { 
    UIBarButtonItem *_backButton = [[UIBarButtonItem alloc] initWithTitle:@"Back" style:UIBarButtonItemStyleDone target:nil action:nil]; 
    self.myNavigationItem.backBarButtonItem = _backButton; 
    [_backButton release]; 
} 

但目前仍無backBarButtonItem的看法？如何解決它？

Answer 1

你有實際設置leftBarButtonItem，而不是backBarButtonItem，然後纔是你設置self.hidesBackBarButtonItem後是這樣的：

- (void)viewWillAppear:(BOOL)animated { 
 UIBarButtonItem *_backButton = [[UIBarButtonItem alloc] initWithTitle:@"Back"   style:UIBarButtonItemStyleDone target:nil action:nil]; 
   self.navigationItem.hidesBackButtonItem = YES; 
    self.myNavigationItem.leftBarButtonItem = _backButton; 
      [_backButton release]; 
}