Question

所以我有一个标签栏应用程序，我放了一个像tweeter的效果，当你从标签栏按下一个按钮，箭头滑动到所选按钮，这是一个非常酷的“动画” 但问题是这个箭头总是在我的第一个计划中，当（例如）我想要全屏播放视频时箭头已经存在，当我切换到没有任何标签栏的其他视图时，箭头仍然存在......

我的代码在AppDelegate中。在.h我有：

AppDelegate : NSObject <UIApplicationDelegate, UITabBarControllerDelegate> {

UIImageView *tabBarArrow;

}

@property (nonatomic, retain) IBOutlet UIWindow *window;

@property (nonatomic, retain) IBOutlet UITabBarController *tabBarController;

@property (nonatomic, retain) UIImageView *tabBarArrow;


- (CGFloat) horizontalLocationFor:(NSUInteger)tabIndex;
- (void) addTabBarArrow;

和我的.m：

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    // Override point for customization after application launch.
    _tabBarController.delegate = self;
    // Add the tab bar controller's current view as a subview of the window

    self.window.rootViewController = self.tabBarController;
    [self addTabBarArrow];
    [self.window makeKeyAndVisible];
    return YES;
}

-(void) addTabBarArrow {
    UIImage* tabBarArrowImage = [UIImage imageNamed:@"Arrow.png"];
    self.tabBarArrow = [[[UIImageView alloc] initWithImage:tabBarArrowImage] autorelease];
    CGFloat verticalLocation = self.window.frame.size.height - _tabBarController.tabBar.frame.size.height
    - tabBarArrowImage.size.height + 6;
    tabBarArrow.frame = CGRectMake([self horizontalLocationFor:0], verticalLocation,
                                   tabBarArrowImage.size.width, tabBarArrowImage.size.height);

    [self.window addSubview:tabBarArrow];
}

-(void)tabBarController:(UITabBarController *)theTabBarController didSelectViewController:(UIViewController *)viewController{
    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDuration:0.2];
    CGRect frame = tabBarArrow.frame;
    frame.origin.x = [self horizontalLocationFor:_tabBarController.selectedIndex];
    tabBarArrow.frame = frame;
    [UIView commitAnimations];
}

-(CGFloat) horizontalLocationFor:(NSUInteger)tabIndex{
    CGFloat tabItemWidth = _tabBarController.tabBar.frame.size.width / _tabBarController.tabBar.items.count;
    CGFloat halfTabItemWidth = (tabItemWidth / 2.0) - (tabBarArrow.frame.size.width / 2.0);

    return (tabIndex * tabItemWidth) + halfTabItemWidth;
}

我认为这就是全部感谢帮助我，因为我真的不知道该怎么做..

Answer 1

我确定它不是你想知道的，但这里已经是http://www.cocoacontrols.com/platforms/ios/controls/bctabbarcontroller的源代码

否则，如果您想调整自己的逻辑，则需要隐藏特定更改的图像视图，例如打开全屏电影。

Answer 2

或者在UITabBarController课程中尝试此操作：

- (void)hideTabBar
{
    for(UIView *view in self.view.subviews)
    {
        if([view isKindOfClass:[UITabBar class]])
        {
            view.hidden = YES;
            break;
        }
    }
}

始终在第一个计划中的图像问题

2 个答案: