使用 UIViewController 的类别 来设置导航栏的显示和隐藏和状态栏的风格

声明:

#import <UIKit/UIKit.h>

@interface UIViewController (Extension)

/** 是否隐藏导航栏 */
@property (nonatomic, assign) BOOL enableHiddenNavBar;

/** 是否使用浅色的状态栏 */
@property (nonatomic, assign) BOOL enableLightContentStyle;

/** 存储当前导航栏的隐藏状态,并设置导航栏的新的隐藏状态 */
-(void)navigationBarToHidden:(BOOL)hidden;

/** 恢复上次存储的导航栏的隐藏状态 */
-(void)recoverOriginalNavigationBarHiddenStatus;

/** 存储当前状态栏的风格,并设置状态栏的新的风格 */
-(void)statusBarStyleToStyle:(UIStatusBarStyle)statusBarStyle;

/** 恢复上次存储的状态栏的风格 */
-(void)recoverOriginalStatusBarStyle;

@end

实现:

#import "UIViewController+Extension.h"
#import <objc/message.h>

@implementation UIViewController (Extension)
@dynamic enableHiddenNavBar;
@dynamic enableLightContentStyle;

/** 需要隐藏导航栏的视图控制器数组 */
static NSMutableArray *hiddenNavBarControllersArr_;

/** 需要使用浅色状态栏的视图控制器数组 */
static NSMutableArray *lightContentStatusBarControllersArr_;

/** 单次执行 */
+(void)load{
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        Method originalMethod = class_getInstanceMethod(self, @selector(viewWillAppear:));
         Method newMethod = class_getInstanceMethod(self, @selector(dy_viewWillAppear:));
        method_exchangeImplementations(originalMethod, newMethod);
        hiddenNavBarControllersArr_ = [NSMutableArray array];
        lightContentStatusBarControllersArr_ = [NSMutableArray array];

    });
}

/** 调换系统的方法 */
-(void)dy_viewWillAppear:(BOOL)animated{

    /** 导航栏的显示和隐藏 */
    if ([hiddenNavBarControllersArr_ containsObject:NSStringFromClass([self class])]) {
        [self.navigationController setNavigationBarHidden:YES animated:NO];
    }else{
        [self.navigationController setNavigationBarHidden:NO animated:NO];
    }

    /** 状态栏的显示和隐藏 */
    if ([lightContentStatusBarControllersArr_ containsObject:NSStringFromClass([self class])]) {
        [UIApplication sharedApplication].statusBarStyle = UIStatusBarStyleLightContent;
    }else{
        [UIApplication sharedApplication].statusBarStyle = UIStatusBarStyleDefault;
    }

    /** 重新调用系统的方法 */
    [self dy_viewWillAppear:animated];
}

/** 是否隐藏导航栏 */
- (void)setEnableHiddenNavBar:(BOOL)enableHiddenNavBar{
    if (enableHiddenNavBar) {
        if (![hiddenNavBarControllersArr_ containsObject:NSStringFromClass([self class])]) {
            [hiddenNavBarControllersArr_ addObject:NSStringFromClass([self class])];
        }
    }
};

/** 是否使用浅色的状态栏 */
- (void)setEnableLightContentStyle:(BOOL)enableLightContentStyle{
    if (enableLightContentStyle) {
        if (![lightContentStatusBarControllersArr_ containsObject:NSStringFromClass([self class])]) {
            [lightContentStatusBarControllersArr_ addObject:NSStringFromClass([self class])];
        }
    }
};

 /** 导航栏和状态栏的存储的 key */
static const NSString * lastNavigationBarHiddenStatusKey= @"lastStatusBarStyleKey";
static const NSString * lastStatusBarStyleKey= @"lastStatusBarStyleKey";

/** 存储当前导航栏的隐藏状态,并设置导航栏的新的隐藏状态 */
-(void)navigationBarToHidden:(BOOL)hidden{
    NSNumber *lastNavigationBarHiddenStatus = [NSNumber numberWithBool:self.navigationController.navigationBarHidden];
    objc_setAssociatedObject(self, [lastNavigationBarHiddenStatusKey UTF8String], lastNavigationBarHiddenStatus, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
    [self.navigationController setNavigationBarHidden:hidden animated:NO];
}

/** 恢复上次存储的导航栏的隐藏状态 */
-(void)recoverOriginalNavigationBarHiddenStatus{
    NSNumber *lastNavigationBarHiddenStatus = objc_getAssociatedObject(self, [lastNavigationBarHiddenStatusKey UTF8String]);
    if (lastNavigationBarHiddenStatus == nil) {
        lastNavigationBarHiddenStatus = [NSNumber numberWithBool:self.navigationController.navigationBarHidden];
    }
    [self.navigationController setNavigationBarHidden:[lastNavigationBarHiddenStatus boolValue] animated:NO];

}

/** 存储当前状态栏的风格,并设置状态栏的新的风格 */
-(void)statusBarStyleToStyle:(UIStatusBarStyle)statusBarStyle{
    NSNumber *lastStatusBarStyle = [NSNumber numberWithInteger:[UIApplication sharedApplication].statusBarStyle];
    objc_setAssociatedObject(self, [lastStatusBarStyleKey UTF8String], lastStatusBarStyle, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
    [UIApplication sharedApplication].statusBarStyle = statusBarStyle;
}

/** 恢复上次存储的状态栏的风格 */
-(void)recoverOriginalStatusBarStyle{
    NSNumber *lastStatusBarStyle = objc_getAssociatedObject(self, [lastStatusBarStyleKey UTF8String]);
    if (lastStatusBarStyle  == nil) {
        lastStatusBarStyle = [NSNumber numberWithInteger:[UIApplication sharedApplication].statusBarStyle];
    }
    [UIApplication sharedApplication].statusBarStyle = [lastStatusBarStyle integerValue];
}

@end

// - 注释:
这里的思路是用两个数组分别来存储隐藏导航栏的视图控制的名称白色状态栏的视图控制器的名称, 在 +(void)load 方法中交换系统的 viewWillAppear 和自定的 viewWillAppear 在自定义的 viewWillAppear 方法中判断数组中是否有当前的视图控制器,如果存在则设置隐藏导航栏和白色的状态栏 ,否则不隐藏和使用默认的状态栏样式