设置 tabBarAppearance 使得 UITabBarItem 不尊重`imageInsets`答案

【问题标题】：Setting tabBarAppearance makes it so UITabBarItem doesn't respect `imageInsets`设置 tabBarAppearance 使得 UITabBarItem 不尊重`imageInsets`
【发布时间】：2022-01-24 03:13:01
【问题描述】：

当我设置 UITabBar 的外观时，它使得 UITabBarItem 的 imageInsets 和 titlePositionAdjustment 在 iOS 15 上不再受到尊重。删除线 [UITabBar appearance].standardAppearance = tabBarAppearance; 使其成为图像和标签阵容但背景颜色无法设置。有没有人遇到过这样的问题并解决了？

代码：

UITabBarAppearance *tabBarAppearance = [[UITabBarAppearance alloc] init];
[tabBarAppearance configureWithOpaqueBackground];
[UITabBar appearance].standardAppearance = tabBarAppearance;
[UITabBar appearance].scrollEdgeAppearance = tabBarAppearance;

static let tabBarImageInsets: UIEdgeInsets = UIEdgeInsets(top: 4.0, left: 0, bottom: -4.0, right: 0)
static let titlePositionAdjustmentValue: UIOffset = UIOffset(horizontal: 0.0, vertical: -8.0)
tabBarItem.imageInsets = tabBarImageInsets
tabBarItem.titlePositionAdjustment = titlePositionAdjustmentValue

图片：

Tab Bar with appearance and misaligned label

Tab Bar without appearance, properly aligned label and image, and no background

【问题讨论】：

标签： ios swift objective-c uitabbar

【解决方案1】：

我在实际阅读 Apple 文档后解决了这个问题：

if (@available(iOS 15.0, *)) {
        UINavigationBarAppearance *navBarAppearance = [[UINavigationBarAppearance alloc] init];
        [navBarAppearance configureWithOpaqueBackground];
        [UINavigationBar appearance].standardAppearance = navBarAppearance;
        [UINavigationBar appearance].compactAppearance = navBarAppearance;
        [UINavigationBar appearance].scrollEdgeAppearance = navBarAppearance;

        UITabBarAppearance *tabBarAppearance = [[UITabBarAppearance alloc] init];
        [tabBarAppearance configureWithOpaqueBackground];
        [UITabBar appearance].standardAppearance = tabBarAppearance;
        [UITabBar appearance].scrollEdgeAppearance = tabBarAppearance;

        UITabBarItemAppearance *tabBarItemAppearance = [[UITabBarItemAppearance alloc] init];

        tabBarItemAppearance.normal.titleTextAttributes = [[RRUIDesignToken.font nav] makeTextAttributes];
        if ([UIDevice currentDevice].userInterfaceIdiom == UIUserInterfaceIdiomPad) {
            tabBarItemAppearance.normal.titlePositionAdjustment = UIOffsetMake(0.0, -[RRUIDesignToken.size paddingXsmall]);
        } else {
            tabBarItemAppearance.normal.titlePositionAdjustment = UIOffsetMake(0.0, -[RRUIDesignToken.size paddingXxsmall]);
        }

        tabBarAppearance.stackedLayoutAppearance = tabBarItemAppearance;
        tabBarAppearance.compactInlineLayoutAppearance = tabBarItemAppearance;
        tabBarAppearance.inlineLayoutAppearance = tabBarItemAppearance;
    }

【讨论】：