WF: _WebFilterIsActive returnin

错误提示如下:

 WF: _userSettingsForUser mobile: {
filterBlacklist =     (
);
filterWhitelist =     (
);
restrictWeb = 1;
useContentFilter = 0;
useContentFilterOverrides = 0;
whitelistEnabled = 0;
}

WF: _WebFilterIsActive returning: NO
WF: _userSettingsForUser mobile: {
filterBlacklist =     (
);
filterWhitelist =     (
);
restrictWeb = 1;
useContentFilter = 0;
useContentFilterOverrides = 0;
whitelistEnabled = 0;
}
 WF: _WebFilterIsActive returning: NO
 [Bugly]  Trapped uncaught exception  'NSInvalidArgumentException', reason: 'Can't add self as subview' `

这段可以跳过，是我问题出现的方式:
（程序启动后，快速的点击屏幕，因为有一个广告页，会跳转广告页，但是在跳转广告页之前，我会先切换程序的根控制器，在延时1秒跳转广告详情页，这时会显示程序的首页，首页我做了缓存处理，正好点击的位置是首页的滚动广告，这时又跳转一个广告页，最终的结果是只跳转了时候首页的广告，但是点击返回的时候，无法返回，并崩溃，报如上错误！）

现在说一下这个排查思路：

1. 拿这些打印去找度娘，首先我拿的是WF: _WebFilterIsActive returning: NO ，（为啥拿这段，因为这个打印我没见过，比较特殊，我一般都是拿那些不常见的打印去查，你也可以这样），搜索出来的结果其中一个链接，问题的矛头都指向了UIWebview，
   AA4A486A-4573-4241-801E-777D6FD7805F.png
   解决办法也很简单，就是把UIWebView更换为WKWebView，我当然按照文档的指示，换好之后，继续测试，发现问题还是存在
2. 既然问题还存在，说明不是UIWebView的问题，我把关注点放在 'Can't add self as subview'这句话上，查下来的结果认为是连续push两个控制器导致，这和我的问题是吻合的，直接按照文档的指示开始操作，链接
   我其实也看其他人写的了，对于我来说改起来比较麻烦，这个是最简单的办法，运用了运行时！

现在问题完美的解决了，我也把自己的代码分享出来，希望帮助遇到同样问题的你！
下面贴上代码！

1. 首先创建一个分类（分类名为UINavigationController+SafePushing，可以随便起哈）
2. 复制下面的代码到.m文件
3. 创建UINavigationController的时候引入分类
   大功告成！

#import "UINavigationController+SafePushing.h"
#import <objc/runtime.h>




/// This char is used to add storage for the isPushingViewController property.
static char const * const ObjectTagKey = "ObjectTag";

@interface UINavigationController ()<UINavigationControllerDelegate>
@property (readwrite,getter = isViewTransitionInProgress) BOOL viewTransitionInProgress;
@end

@implementation UINavigationController (SafePushing)
- (void)setViewTransitionInProgress:(BOOL)property {
NSNumber *number = [NSNumber numberWithBool:property];
objc_setAssociatedObject(self, ObjectTagKey, number , OBJC_ASSOCIATION_RETAIN);
}

- (BOOL)isViewTransitionInProgress {
NSNumber *number = objc_getAssociatedObject(self, ObjectTagKey);
return [number boolValue];
}

#pragma mark - Intercept Pop, Push, PopToRootVC
/// @name Intercept Pop, Push, PopToRootVC
- (NSArray *)safePopToRootViewControllerAnimated:(BOOL)animated {
if (self.viewTransitionInProgress) return nil;
if (animated) {
    self.viewTransitionInProgress = YES;
}
//-- This is not a recursion, due to method swizzling the call below calls the original  method.
return [self safePopToRootViewControllerAnimated:animated];
}

- (NSArray *)safePopToViewController:(UIViewController *)viewController animated:(BOOL)animated {
if (self.viewTransitionInProgress) return nil;
if (animated) {
    self.viewTransitionInProgress = YES;
}
//-- This is not a recursion, due to method swizzling the call below calls the original  method.
return [self safePopToViewController:viewController animated:animated];
}

- (UIViewController *)safePopViewControllerAnimated:(BOOL)animated {
if (self.viewTransitionInProgress) return nil;
if (animated) {
    self.viewTransitionInProgress = YES;
}
//-- This is not a recursion, due to method swizzling the call below calls the original  method.
return [self safePopViewControllerAnimated:animated];
}

- (void)safePushViewController:(UIViewController *)viewController animated:(BOOL)animated {
self.delegate = self;
//-- If we are already pushing a view controller, we dont push another one.
if (self.isViewTransitionInProgress == NO) {
    //-- This is not a recursion, due to method swizzling the call below calls the original  method.
    [self safePushViewController:viewController animated:animated];
    if (animated) {
        self.viewTransitionInProgress = YES;
    }
}
}

// This is confirmed to be App Store safe.
// If you feel uncomfortable to use Private API, you could also use the delegate method navigationController:didShowViewController:animated:.
- (void)safeDidShowViewController:(UIViewController *)viewController animated:(BOOL)animated {
//-- This is not a recursion. Due to method swizzling this is calling the original method.
[self safeDidShowViewController:viewController animated:animated];
self.viewTransitionInProgress = NO;
}


// If the user doesnt complete the swipe-to-go-back gesture, we need to intercept it and set the flag to NO again.
- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated {
id<UIViewControllerTransitionCoordinator> tc = navigationController.topViewController.transitionCoordinator;
[tc notifyWhenInteractionEndsUsingBlock:^(id<UIViewControllerTransitionCoordinatorContext> context) {
    self.viewTransitionInProgress = NO;
    //--Reenable swipe back gesture.
    self.interactivePopGestureRecognizer.delegate = (id<UIGestureRecognizerDelegate>)viewController;
    [self.interactivePopGestureRecognizer setEnabled:YES];
}];
//-- Method swizzling wont work in the case of a delegate so:
//-- forward this method to the original delegate if there is one different than ourselves.
if (navigationController.delegate != self) {
    [navigationController.delegate navigationController:navigationController
                                 willShowViewController:viewController
                                               animated:animated];
}
}

+ (void)load {
//-- Exchange the original implementation with our custom one.
method_exchangeImplementations(class_getInstanceMethod(self, @selector(pushViewController:animated:)), class_getInstanceMethod(self, @selector(safePushViewController:animated:)));
//    method_exchangeImplementations(class_getInstanceMethod(self, @selector(didShowViewController:animated:)), class_getInstanceMethod(self, @selector(safeDidShowViewController:animated:)));
method_exchangeImplementations(class_getInstanceMethod(self, @selector(popViewControllerAnimated:)), class_getInstanceMethod(self, @selector(safePopViewControllerAnimated:)));
method_exchangeImplementations(class_getInstanceMethod(self, @selector(popToRootViewControllerAnimated:)), class_getInstanceMethod(self, @selector(safePopToRootViewControllerAnimated:)));
method_exchangeImplementations(class_getInstanceMethod(self, @selector(popToViewController:animated:)), class_getInstanceMethod(self, @selector(safePopToViewController:animated:)));
}


@end