解决iOS7自定义返回按钮后不能侧滑返回的问题

iOS7自带侧滑返回功能，但是自定义返回按钮之后，侧滑返回功能会失效，解决办法如下：

自定义一个UINavigationController，实现几个代理方法

@interface CustomNavigationController : UINavigationController

@end

#import "CustomNavigationController.h"

@interface CustomNavigationController ()<UINavigationControllerDelegate, UIGestureRecognizerDelegate>
@property(nonatomic, weak) UIViewController *currentShowVC;
@end

@implementation CustomNavigationController

- (instancetype)initWithRootViewController:(UIViewController *)rootViewController {
  CustomNavigationController *nav = [super initWithRootViewController:rootViewController];
  nav.interactivePopGestureRecognizer.delegate = self;
  nav.delegate = self;
  return nav;
}

- (void)navigationController:(UINavigationController *)navigationController didShowViewController:(UIViewController *)viewController animated:(BOOL)animated {
  if (1 == navigationController.viewControllers.count) {
    self.currentShowVC = nil;
  } else {
    self.currentShowVC = viewController;
  }
}

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer {
  if (gestureRecognizer == self.interactivePopGestureRecognizer) {
    return (self.currentShowVC == self.topViewController);
  }
  return YES;
}

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer {
  if ([gestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]] &&
      [otherGestureRecognizer isKindOfClass:[UIScreenEdgePanGestureRecognizer class]]) {
    return YES;
  } else {
    return NO;
  }
}
@end

然后，将你的UINavigationController都替换成该自定的NavigationController就OK了