iOS15 导航栏属性设置及适配

标题文字

• viewController：self.title
• 返回值是 view 的方法去设置 titleView

标题颜色

// iOS 15之前
bar.titleTextAttributes = @{NSForegroundColorAttributeName: itemColor};
// iOS 15之后
if (@available(iOS 13.0, *)) { // 因为 api 是从13出的
    UINavigationBarAppearance *appearance = UINavigationBarAppearance.new;
    appearance.titleTextAttributes = @{NSForegroundColorAttributeName: itemColor};
    bar.standardAppearance = appearance;
    bar.scrollEdgeAppearance = appearance;
}

导航栏颜色

// iOS 15 之前
// 如果设置了背景图片为空图片,必须要禁用穿透效果,才能看到 barTintColor -- self.navigationBar.translucent = NO
navigationBar.barTintColor
或 navigationBar.subviews[0]

// iOS 15 之后
UINavigationBarAppearance *appearance = UINavigationBarAppearance.new;
appearance.backgroundColor = UIColor.whiteColor;
...
naviBar.standardAppearance = appearance;
naviBar.scrollEdgeAppearance = appearance;

导航栏控件颜色

naviBar.tintColor

导航栏隐藏

naviBar.hidden = true

导航栏透明 -- 隐藏分隔线

// 法一 navigationContentView 透明
// 参考：《UINavgationBar全透明一行代码实现/ 任意颜色》
// 但在 iOS 15 适配了导航栏后，设置alpha的方法会使适配无效
navigationBar.subviews[0].alpha = 0;

// 法二 背景色置空 + 阴影图片置空
// 在 iOS 15 适配了导航栏时需要显式标明 shadowColor(在 shadowImage 为 nil 时，shadowColor 生效)，故虽已经隐藏了分割线，但导航栏下方仍会出现类似分割线的阴影
// 解决方案：需手动标明 shadowColor 为 clearColor 或 nil
[nav.navigationBar setBackgroundImage:[UIImage new] forBarMetrics:UIBarMetricsDefault];
[nav.navigationBar setShadowImage:[UIImage new]];
// iOS15 后加入这段代码 
if (@available(iOS 13.0, *)) { // 因为 api 是从13出的
    UINavigationBarAppearance *appearance = UINavigationBarAppearance.new;
    appearance.shadowColor = UIColor.clearColor;
    bar.standardAppearance = appearance;
    bar.scrollEdgeAppearance = appearance;
}

iOS15 导航栏及tabBar适配

《iOS 15 透明导航栏设置》

解决 iOS 15 中页面跳转导航栏暂存及无底色问题
分析：类似 VC，必须要设置 backgroundColor

- (void)setupAppearance {
    Class baseClass = UINavigationController.class; // 可定制某一个类型
    UIColor *bgColor = UIColor.whiteColor;
    UIColor *separatorColor = UIColor.redColor;
    NSDictionary *defaultTitleTextAttr = @{NSForegroundColorAttributeName: UIColor.blackColor};

    [UITabBar appearance].barTintColor = bgColor;
    UINavigationBar *naviBar = [UINavigationBar appearanceWhenContainedInInstancesOfClasses:@[baseClass]];
    naviBar.barTintColor = bgColor; // 设置导航栏颜色(ios15 之前生效)
    naviBar.shadowImage = [UIImage imageWithColor: separatorColor];
    [naviBar setBackgroundImage:[UIImage imageWithColor:bgColor] forBarMetrics:UIBarMetricsDefault];
    naviBar.titleTextAttributes = defaultTitleTextAttr;
        
    if (@available(iOS 13.0, *)) {
        UINavigationBarAppearance *appearance = UINavigationBarAppearance.new;
        appearance.backgroundColor = bgColor; //设置导航栏背景色
        appearance.shadowColor = separatorColor; // 设置分割线默认颜色
        appearance.titleTextAttributes = defaultTitleTextAttr; //设置导航条标题颜色
        [UINavigationBar appearance].standardAppearance = appearance;
        [UINavigationBar appearance].scrollEdgeAppearance = appearance;
    }
}

baseVC 提供设置导航栏接口

目的：提供快捷方法，并在页面跳转时自动复原为默认效果

// baseVC.h
/// 单页面设置隐藏导航栏分割线
@property (nonatomic, assign) BOOL hideNaviBarSeparatorLine;
/// 单页面设置导航栏透明度
@property (nonatomic, assign) BOOL isNaviBarTranslucent;
/// 单页面设置导航栏标题字体
@property (nonatomic, copy) NSDictionary *naviBarTitleTextAttributes;

// baseVC.m
- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
    if (self.navigationController &&
        (self.hideNaviBarSeparatorLine || self.isNaviBarTranslucent || self.naviBarTitleTextAttributes.count > 0)) {
        [self base_updateNaviBarStyle];
    }
}

- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];
    if (self.navigationController &&
        (self.hideNaviBarSeparatorLine || self.isNaviBarTranslucent || self.naviBarTitleTextAttributes.count > 0)) {
        [self base_resetNaviBarStyle];
    }
}

- (void)base_updateNaviBarStyle {
    UIColor *separatorColor = UIColor.redColor;
    NSDictionary *defaultTextAttributes = @{NSForegroundColorAttributeName: UIColor.blackColor};
    
    UINavigationBar *bar = self.navigationController.navigationBar;
    [bar setBackgroundImage:UIImage.new forBarMetrics:UIBarMetricsDefault];
    UIImage *shadowImage = UIImage.new;
    if (!self.hideNaviBarSeparatorLine) {
        shadowImage = [UIImage imageWithColor:separatorColor];
    }
    bar.shadowImage = shadowImage;
    bar.translucent = self.isNaviBarTranslucent;
    NSDictionary *textAttributes = self.naviBarTitleTextAttributes ?: defaultTextAttributes;
    bar.titleTextAttributes = textAttributes;
    
    if (@available(iOS 13.0, *)) {
        UINavigationBarAppearance *appearance = UINavigationBarAppearance.new;
        if  (self.isNaviBarTranslucent) {
            [appearance configureWithTransparentBackground];
        } else {
            [appearance configureWithOpaqueBackground];
        }
        //设置导航栏背景色
        appearance.backgroundColor = self.isNaviBarTranslucent ? UIColor.clearColor : UIColor.whiteColor;
        appearance.shadowColor = self.hideNaviBarSeparatorLine ? UIColor.clearColor : separatorColor;
        //设置导航条标题颜色
        appearance.titleTextAttributes = textAttributes;
        bar.standardAppearance = appearance;
        bar.scrollEdgeAppearance = appearance;
    }
}


- (void)base_resetNaviBarStyle {
    UIColor *separatorColor = UIColor.redColor;
    NSDictionary *defaultTextAttributes = @{NSForegroundColorAttributeName: UIColor.blackColor};
    
    UINavigationBar *bar = self.navigationController.navigationBar;
    [bar setBackgroundImage:UIImage.new forBarMetrics:UIBarMetricsDefault];
    UIImage *shadowImage = [UIImage imageWithColor:separatorColor];
    bar.shadowImage = shadowImage;
    bar.translucent = NO;
    bar.titleTextAttributes = defaultTextAttributes;
    
    if (@available(iOS 13.0, *)) {
        UINavigationBarAppearance *appearance = UINavigationBarAppearance.new;
        [appearance configureWithOpaqueBackground];
        //设置导航栏背景色
        appearance.backgroundColor = UIColor.whiteColor;
        appearance.shadowColor = separatorColor;
        //设置导航条标题颜色
        appearance.titleTextAttributes = defaultTextAttributes;
        bar.standardAppearance = appearance;
        bar.scrollEdgeAppearance = appearance;
    }
}