ios - iOS：删除的取消按钮在使用搜索控制器后重新出现

Question

我在我的应用程序中使用 ABPeoplePickerNavigationController，并使用 UINavigationControllerDelegate 将导航栏按钮覆盖到我自己的位置。

- (void)navigationController:(UINavigationController *)navigationController didShowViewController:(UIViewController *)viewController animated:(BOOL)animated
{
    navigationController.topViewController.searchDisplayController.searchBar.barStyle = UIBarStyleBlack;

    navigationController.topViewController.navigationItem.leftBarButtonItem = nil;
    navigationController.topViewController.navigationItem.rightBarButtonItem = nil;

    UIBarButtonItem *cancelButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemCancel
                                                                                      target:self
                                                                                      action:@selector(cancel:)];
    navigationController.topViewController.navigationItem.leftBarButtonItem = cancelButtonItem;

    UIBarButtonItem *addButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd
                                                                                       target:self
                                                                                       action:@selector(addItem:)];
    navigationController.topViewController.navigationItem.rightBarButtonItem = addButtonItem;

}

这工作正常。但是，当我使用搜索控制器并退出它时，我的右上角按钮突然变为取消按钮（见下图）。我怎样才能解决这个问题？提前致谢。

Answer 1

好的，刚刚想出了如何解决这个问题。我刚刚添加了一个通知以查看何时隐藏键盘并将按钮添加回导航栏。

1）声明并综合属性mainNavigationController：

@property UINavigationController *mainNavigationController;

2) 在 (void)navigationController:(UINavigationController *)navigationController didShowViewController:(UIViewController *)viewController animated:(BOOL)animated 中，添加：

mainNavigationController = navigationController;
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(onNotification:) name:UIKeyboardWillHideNotification object:nil];

3）添加onNotification方法：

-(void)onNotification:(NSNotification*)notification
{
    UIBarButtonItem *addButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd
                                                                                   target:self
                                                                                   action:@selector(addItem:)];
    mainNavigationController.topViewController.navigationItem.rightBarButtonItem = addButtonItem;
}

Answer 2

要解决此问题，您必须实现<UISearchDisplayDelegate>and 在navigationController:willShowViewController:animated:方法中将 searchDisplayController 的委托设置为 selfviewController.searchDisplayController.delegate = self;