无法在 iOS 13 中设置标签栏阴影图像

Question

在 iOS13 之前，我使用下面的代码来移除标签栏上边框：

UITabBar.appearance().shadowImage = UIImage()
UITabBar.appearance().backgroundImage = UIImage()

但它不适用于 iOS13，我正在寻找解决方案。 你有什么想法吗？

Answer 1

Swift 4+：

在您的 TabBarController class 中写下：

 if #available(iOS 13, *) {
        let appearance = self.tabBar.standardAppearance.copy()
        appearance.backgroundImage = UIImage()
        appearance.shadowImage = UIImage()
        appearance.shadowColor = .clear
        self.tabBar.standardAppearance = appearance
    } else {
        self.tabBar.shadowImage = UIImage()
        self.tabBar.backgroundImage = UIImage()
    }

对于标题调整使用这个：

appearance.stackedLayoutAppearance.normal.titlePositionAdjustment = UIOffset(horizontal: 0, vertical: -12)

用于物镜 C

  if (@available(iOS 13.0, *)) {
    UITabBarAppearance* appearance =  self.tabBar.standardAppearance.copy;
    appearance.backgroundImage = [UIImage new];
    appearance.shadowImage = [UIImage new];
    appearance.shadowColor = [UIColor clearColor];
    // Title adjustment
    appearance.stackedLayoutAppearance.normal.titlePositionAdjustment = UIOffsetMake(0, -12);
    self.tabBar.standardAppearance = appearance;
} else {
    self.tabBar.shadowImage = [UIImage new];
    self.tabBar.backgroundImage = [UIImage new];
}

Answer 2

在 iOS 13 中，您可以使用基于外观的方法以及用于配置透明度的内置方法：

    if #available(iOS 13, *) {
        let appearance = self.tabBar.standardAppearance.copy()
        appearance.configureWithTransparentBackground()
        tabBar.standardAppearance = appearance
    } else {
        tabBar.backgroundImage = UIImage()
        tabBar.shadowImage = UIImage()
        tabBar.barTintColor = UIColor.clear
    }

要再次更改它，您可以使用 configureWithDefaultBackground() 执行相同操作：

    if #available(iOS 13, *) {
        let appearance = self.tabBar.standardAppearance.copy()
        appearance.configureWithDefaultBackground()
        tabBar.standardAppearance = appearance
    } else {
        tabBar.barTintColor = nil
        tabBar.backgroundImage = nil
        tabBar.shadowImage = nil
    }