iphone - 如何在我没有子类化的 UITabBarController 上隐藏 UITabBar？

Question

视觉上这就是我想要的

我有一个 UITabBarController .我想隐藏 UITabBar当用户进入中间标签时。中间选项卡加载 B 类的 View Controller 。这是流行的相机应用程序的行为 Instagram .他们的中间标签加载了一个全屏摄像头。

-------------    -------------    -------------
|     VC    |    |     VC    |    |     VC    |
|    for    |    |    for    |    |    for    |
|     A     |    |     B     |    |     C     |
|           |    |           |    |           |
|------------    |           |    |------------
{ A } B | C |    |           |    | A | B { C }
-------------    -------------    -------------

所有其他相关 StackExchange 问题的建议解决方案

我们已经有很多关于在推送特定 View Controller 时如何隐藏 UITabBar 的问题。普遍的共识是:

b.hidesBottomBarWhenPushed = YES;
[self.navigationController pushViewController:b
                                     animated:YES];

我的问题是，我从未将 UITabBarController 子类化。我在 Interface Builder 中创建了它。我从不手动推送我的 View Controller ，所以上面的解决方案对我不起作用。

失败尝试 1

在我的中间 View Controller 中，我在构造函数中打开 hidesBottomBarWhenPushed。这没有效果。

@implementation B

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil {
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        self.hidesBottomBarWhenPushed = YES;
    }
    return self;
}

失败尝试2

我还尝试将我的应用委托(delegate)分配为 UITabBarControllerDelegate .当 UITabBarController 通知我选项卡已被点击时，我仅为中间 View Controller 打开 hidesBottomBarWhenPushed。这也无法隐藏 UITabBar。

#pragma mark UIApplicationDelegate

- (void)applicationDidFinishLaunching:(UIApplication *)application
{
    [window addSubview:self.rootViewController.view];
    [window makeKeyAndVisible];
    self.rootViewController.delegate = self;
}

#pragma mark UITabBarControllerDelegate

- (void) tabBarController:(UITabBarController *)tabBarController 
didSelectViewController:(UIViewController *)viewController
{
    if ([viewController isKindOfClass:[B class]]) {
        viewController.hidesBottomBarWhenPushed = YES;
    } else {
        viewController.hidesBottomBarWhenPushed = NO;
    }
}

Answer 1

- (void) hidetabbar:(BOOL)hiddenTabBar
{
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:0.5];
    for(UIView *view in self.uiTabBarController.view.subviews){
        if([view isKindOfClass:[UITabBar class]]) {

            if (hiddenTabBar) {
                [view setFrame:CGRectMake(view.frame.origin.x, 431, view.frame.size.width, view.frame.size.height)];
            } else {
                [view setFrame:CGRectMake(view.frame.origin.x, 480, view.frame.size.width, view.frame.size.height)];
            }
        } else {
            if (hiddenTabBar) {
                [view setFrame:CGRectMake(view.frame.origin.x, view.frame.origin.y, view.frame.size.width, 431)];
            } else {
                [view setFrame:CGRectMake(view.frame.origin.x, view.frame.origin.y, view.frame.size.width, 480)];
            }
        }
    }
    [UIView commitAnimations];  
    hiddenTabBar = !hiddenTabBar;
}