通用iOS应用程序中的自定义选项卡栏

我希望重新创建在许多应用程序中看到的凸起的标签栏，但我希望在一个需要改变凸起位置的通用应用程序中这样做

目前，我没有太多的运气创造这一点，所以我来到这里的启示，如果没有这一点，我可能只是创建一个自定义选项卡栏背景

如果是这样的话，这会在应用程序委托中起作用以区分这两种设备吗

if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad) {

UITarBar *tabBar = [UITabBar appearance];
[tabBar setBackgroundImage: [UIImage imageNamed:@"iPadtabBar.png"]];

}
else {

UITarBar *tabBar = [UITabBar appearance];
[tabBar setBackgroundImage: [UIImage imageNamed:@"iPhonetabBar.png"]];

}

---

你可能会想，他为什么不直接测试一下。。好吧，那会更容易，如果可以的话，我宁愿先问一下，但我要到下周初才能拿到我的Mac电脑

您必须将uitabarcontroller子类化并自定义该中心选项卡按钮。这里有一个很好的例子：

头文件： @界面CustomTabBarViewController:UITabBarController{ }

实施文件：

@implementation CustomTabBarViewController

// Create a view controller and setup it's tab bar item with a title and image
-(UIViewController*) viewControllerWithTabTitle:(NSString*) title image:(UIImage*)image
{
    UIViewController* viewController = [[UIViewController alloc] init];
    viewController.tabBarItem = [[UITabBarItem alloc] initWithTitle:title image:image tag:0];
    return viewController;
}

// Create a custom UIButton and add it to the center of our tab bar
-(void) addCenterButtonWithImage:(UIImage*)buttonImage highlightImage:(UIImage*)highlightImage
{
    UIButton* button = [UIButton buttonWithType:UIButtonTypeCustom];
    button.autoresizingMask = UIViewAutoresizingFlexibleRightMargin | UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleBottomMargin | UIViewAutoresizingFlexibleTopMargin;
    button.frame = CGRectMake(0.0, 0.0, buttonImage.size.width, buttonImage.size.height);
    [button setBackgroundImage:buttonImage forState:UIControlStateNormal];
    [button setBackgroundImage:highlightImage forState:UIControlStateHighlighted];

    CGFloat heightDifference = buttonImage.size.height - self.tabBar.frame.size.height;
    if (heightDifference < 0)
        button.center = self.tabBar.center;
    else
    {
        CGPoint center = self.tabBar.center;
        center.y = center.y - heightDifference/2.0;
        button.center = center;
    }

    [self.view addSubview:button];
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    return YES;
}

@end

---

这样行吗？设备或模拟器比这里的任何人都更清楚。但更重要的是，在应用程序委托中这样做几乎肯定是错误的。@nhgrif有时我会看到在应用程序委托中设置了选项卡栏。与在故事板或主视图控制器中进行比较，这可能不是普遍接受的方法，但我以前在UITabBar或UITabBarController子类中看到过这样做……这个答案至少应该包括所提供链接中的示例代码段突出显示。子类化uitabarcontroller的基础不太可能在短期内发生太大的变化。。。然而，链接到网站，尤其是非官方文档网站的链接有消亡的趋势，这使得答案完全无用。我通过故事板和许多CollectionViewController来完成所有这些，我需要在选项卡栏上的故事板中插入一个按钮吗？另外，如何设置显示的图像？我是否必须将所述子类导入每个viewcontroller？对不起，完全是新手！

@implementation CustomTabBarViewController

// Create a view controller and setup it's tab bar item with a title and image
-(UIViewController*) viewControllerWithTabTitle:(NSString*) title image:(UIImage*)image
{
    UIViewController* viewController = [[UIViewController alloc] init];
    viewController.tabBarItem = [[UITabBarItem alloc] initWithTitle:title image:image tag:0];
    return viewController;
}

// Create a custom UIButton and add it to the center of our tab bar
-(void) addCenterButtonWithImage:(UIImage*)buttonImage highlightImage:(UIImage*)highlightImage
{
    UIButton* button = [UIButton buttonWithType:UIButtonTypeCustom];
    button.autoresizingMask = UIViewAutoresizingFlexibleRightMargin | UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleBottomMargin | UIViewAutoresizingFlexibleTopMargin;
    button.frame = CGRectMake(0.0, 0.0, buttonImage.size.width, buttonImage.size.height);
    [button setBackgroundImage:buttonImage forState:UIControlStateNormal];
    [button setBackgroundImage:highlightImage forState:UIControlStateHighlighted];

    CGFloat heightDifference = buttonImage.size.height - self.tabBar.frame.size.height;
    if (heightDifference < 0)
        button.center = self.tabBar.center;
    else
    {
        CGPoint center = self.tabBar.center;
        center.y = center.y - heightDifference/2.0;
        button.center = center;
    }

    [self.view addSubview:button];
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    return YES;
}

@end