nav导航栏相关

tabBar、nav、statusBar高度

#define kStatusBarHeight UIApplication.sharedApplication.statusBarFrame
#define kTabBarHeight    self.tabBarController.tabBar.frame.size.height
#define kNavBarHeight    self.navigationController.navigationBar.frame.size.height

-	iPhoneX系列	iPhone8等无刘海
kStatusBarHeight	44	20
kTabBarHeight	83	49
kNavBarHeight(有导航栏)	44	44

- (void)initView {
    self.navigationItem.title = @"E";
    self.view.backgroundColor = [UIColor whiteColor];
    
    //定制返回按钮image
    self.navigationController.navigationBar.backIndicatorImage = [[UIImage imageNamed:@"back2"] imageWithRenderingMode:(UIImageRenderingModeAlwaysOriginal)];
    self.navigationController.navigationBar.backIndicatorTransitionMaskImage = [[UIImage imageNamed:@"back2"] imageWithRenderingMode:(UIImageRenderingModeAlwaysOriginal)];
    
    //nav黑线 (https://blog.csdn.net/hherima/article/details/44218915)
     self.navigationController.navigationBar.clipsToBounds = YES;

    //导航栏背景图片
    UIImage *image = [UIImage imageNamed:@"video-nav"];
    image = [image resizableImageWithCapInsets:UIEdgeInsetsMake(10, 10, 50, 300) resizingMode:(UIImageResizingModeStretch)];
    [self.navigationController.navigationBar setBackgroundImage:image forBarMetrics:UIBarMetricsDefault];


    //设置导航栏标题颜色
    [self.navigationController.navigationBar setTitleTextAttributes:@{NSForegroundColorAttributeName:[UIColor cyanColor]}];

    //导航栏背景色
    self.navigationController.navigationBar.barTintColor = [UIColor lightGrayColor];

    //系统的左右rightBarButtonItem的颜色
    self.navigationController.navigationBar.tintColor = [UIColor orangeColor];
        
    UIBarButtonItem *backItem = [[UIBarButtonItem alloc] init];
    backItem.title = @"返回dd";
    self.navigationItem.backBarButtonItem = backItem;
    
    UIBarButtonItem *rightItem = [[UIBarButtonItem alloc] initWithTitle:@"右边" style:(UIBarButtonItemStylePlain) target:nil action:nil];
    self.navigationItem.rightBarButtonItem = rightItem;

    // 左边按钮和返回按钮共存
    self.navigationItem.leftItemsSupplementBackButton = YES;

}

1 2

• nav半透明

//导航栏背景色 (颜色有偏差，是因为有一层毛玻璃效果视图 取消毛玻璃效果)  这个会影响subview的坐标子控制器视图整体下移
self.navigationController.navigationBar.translucent = NO;
// 视图延伸不考虑透明的Bars(这里包含导航栏和状态栏) 意思就是延伸到边界
self.extendedLayoutIncludesOpaqueBars = YES;

extendedLayoutIncludesOpaqueBars https://www.jianshu.com/p/45ad9fa3f47f
这个属性在状态栏不透明的状态下才生效。也就是说，一般使用这个属性应该这样使用:
{
    // 状态栏不透明(必须设置，并且为NO)
    self.navigationController.navigationBar.translucent = NO;
    
    // 视图延伸不考虑透明的Bars(这里包含导航栏和状态栏)
    // 意思就是延伸到边界
    self.extendedLayoutIncludesOpaqueBars = YES;
}

• 导航栏按钮定制

leftBack@2x.png 21x40

//订制返回按钮
UIButton *btnBack = [UIButton buttonWithType:UIButtonTypeCustom];
btnBack.frame = CGRectMake(0, 0, 45, 40);

[btnBack setImage:[UIImage imageNamed:@"leftBack"] forState:UIControlStateNormal];
[btnBack setImage:[UIImage imageNamed:@"leftBack"] forState:UIControlStateHighlighted];

//内容左对齐
btnBack.contentHorizontalAlignment = UIControlContentHorizontalAlignmentLeft;
btnBack.contentEdgeInsets = UIEdgeInsetsMake(0, 0, 0, 0);

[btnBack addTarget:self action:@selector(buttonClickAction) forControlEvents:UIControlEventTouchUpInside];
UIBarButtonItem *leftBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:btnBack];
self.navigationItem.leftBarButtonItem = leftBarButtonItem;