navigationBar和statusBar

我们都知道一个navigaitonController中的navigationBar是统一的,同时对于statusBar的样式也是,如果需要设置统一风格,最好在navigationController中统一设置.

#import "WBFaceBasicNavigationController.h"

@interface WBFaceBasicNavigationController ()

@end

@implementation WBFaceBasicNavigationController

+(void)initialize{
// 在这里设置所有关于navigationBar的统一的属性
    UINavigationBar * navigationBar = [UINavigationBar appearanceWhenContainedInInstancesOfClasses:@[[self class]]];
    [navigationBar setBackgroundImage:[[UIImage alloc] init] forBarMetrics:UIBarMetricsDefault];
    navigationBar.translucent = YES;
    
    [navigationBar setShadowImage:[UIImage new]];
    [navigationBar setTitleTextAttributes:@{NSForegroundColorAttributeName: [UIColor whiteColor], NSFontAttributeName: [UIFont systemFontOfSize:17]}];
    navigationBar.barTintColor = [UIColor whiteColor];
}

-(void)pushViewController:(UIViewController *)viewController animated:(BOOL)animated{
    viewController.navigationItem.hidesBackButton = YES;
    [super pushViewController:viewController animated:animated];
}

/**
 *  默认返回值为nil。
 *  当我们调用setNeedsStatusBarAppearanceUpdate时，系统会调用application.window的rootViewController的preferredStatusBarStyle
 *  方法
 *  我们的程序里一般都是用UINavigationController做root，如果是这种情况，那我们自己的UIViewController里的preferredStatusBarStyle根本不会被调用
 *  这个时候不要调用我自己(就是UINavigationController)的preferredStatusBarStyle方法，而是去调用navigationController.topViewController的preferredStatusBarStyle方法
 *
 *  @return stack最上层的vc，我们知道navigation是以stack的形式跳转的
 */
- (UIViewController *)childViewControllerForStatusBarStyle {
    return self.topViewController;
}

@end

leftBarbuttonItem和rightBarbuttonItem

+(instancetype)itemWithImage:(NSString *)image selectedImage:(NSString *)selectedImage target:(id)target action:(SEL)action{
    UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
    [button setBackgroundImage:[UIImage imageNamed:image] forState:UIControlStateNormal];
    [button setBackgroundImage:[UIImage imageNamed:selectedImage] forState:UIControlStateSelected];
    button.bounds = CGRectMake(0, 0, 30, 30);
    [button addTarget:target action:action forControlEvents:UIControlEventTouchUpInside];
    return [[self alloc] initWithCustomView:button];
}
@end


self.navigationItem.leftBarButtonItem = [UIBarButtonItem itemWithImage:@"backbutton.png" selectedImage:@"backbutton.png" target:self action:@selector(faceVerifyComeBack)];