如何在更多部分获得UITabBarItem的标题？

Question

我有一个UITabBarControllerDelegate方法来确定标题,UITabBarItem并做相应的事情.这适用于我的项目,UITabBar但是当我点击"更多"按钮时,我的其余部分UITabBarItems都在UITableView.如何在"更多"部分中确定标题？

- (void)tabBarController:(UITabBarController *)tabBarController didSelectViewController:(UIViewController *)viewController
{

    if ([self.tabBarController.selectedViewController.title isEqualToString:@"All"]) {
        //do something
    }
}

Answer 1

无论何时在UITabBarController中选择视图控制器,都会调用您提到的方法,最重要的是,当前显示的视图控制器将作为参数传递给您 ; 然后,您可以使用以下代码查找控制器的类和标题,包括"更多"控制器:

- (void)tabBarController:(UITabBarController *)tabBarController 
 didSelectViewController:(UIViewController *)viewController
{
    NSLog(@"controller class: %@", NSStringFromClass([viewController class]));
    NSLog(@"controller title: %@", viewController.title);
}

在快速测试中,只需在Xcode中添加几个控制器,这就是您在控制台中获得的:

2011-03-28 09:13:21.795 TabTest[39015:207] controller class: UIViewController
2011-03-28 09:13:21.797 TabTest[39015:207] controller title: (null)
2011-03-28 09:13:23.922 TabTest[39015:207] controller class: UITableViewController
2011-03-28 09:13:23.925 TabTest[39015:207] controller title: (null)
2011-03-28 09:13:24.505 TabTest[39015:207] controller class: UITableViewController
2011-03-28 09:13:24.506 TabTest[39015:207] controller title: (null)
2011-03-28 09:13:24.945 TabTest[39015:207] controller class: UIMoreNavigationController
2011-03-28 09:13:24.945 TabTest[39015:207] controller title: More

在另一边,当你选择一个控制器内的"更多"列表中,你会不会在你的UITabBarControllerDelegate方法(怪异的,恕我直言)通知.为了帮助您在该列表中选择控制器时收到通知,您可以执行以下操作:

- (void)tabBarController:(UITabBarController *)tabBarController 
 didSelectViewController:(UIViewController *)viewController
{
    NSLog(@"controller class: %@", NSStringFromClass([viewController class]));
    NSLog(@"controller title: %@", viewController.title);

    if (viewController == tabBarController.moreNavigationController)
    {
        tabBarController.moreNavigationController.delegate = self;
    }
}

- (void)navigationController:(UINavigationController *)navigationController didShowViewController:(UIViewController *)viewController animated:(BOOL)animated
{
    if (navigationController == self.tabBarController.moreNavigationController)
    {
        NSLog(@"more controller class: %@", NSStringFromClass([viewController class]));
        NSLog(@"more controller title: %@", viewController.title);
    }
}

当然,您的类还应该实现UINavigationControllerDelegate协议.

这是样本运行的结果,使用上面的代码并在UITabBar和"更多"列表中点击几次:

2011-03-28 09:27:42.496 TabTest[39113:207] controller class: UIViewController
2011-03-28 09:27:42.498 TabTest[39113:207] controller title: (null)
2011-03-28 09:27:44.306 TabTest[39113:207] controller class: UIMoreNavigationController
2011-03-28 09:27:44.307 TabTest[39113:207] controller title: More
2011-03-28 09:27:44.310 TabTest[39113:207] more controller class: UIMoreListController
2011-03-28 09:27:44.311 TabTest[39113:207] more controller title: More
2011-03-28 09:27:45.632 TabTest[39113:207] more controller class: SecondViewController
2011-03-28 09:27:45.634 TabTest[39113:207] more controller title: (null)
2011-03-28 09:27:47.156 TabTest[39113:207] more controller class: UIMoreListController
2011-03-28 09:27:47.156 TabTest[39113:207] more controller title: More
2011-03-28 09:27:48.581 TabTest[39113:207] controller class: UITableViewController
2011-03-28 09:27:48.582 TabTest[39113:207] controller title: (null)

希望这可以帮助!