objective-c - ios导航栏切换bug，在线等，急

导航栏切换时出现bug。重现方式：在app里点来点去，可能会出现。
当出现该bug时，从首页进入任何带导航栏的页面都会出现此问题。

//项目中使用了下面这个category
#import "UINavigationController+FDFullscreenPopGesture.h"

//自定义首页导航栏的代码
//left item
UIButton *leftItem = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 40, 14)];
self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:leftItem];

//title view
UIImageView *titleImage = [[UIImageView alloc] initWithImage:IMAGE(@"乡味汇横版")];
self.navigationItem.titleView = titleImage;

//right item
UIImageView *rightItem = [[UIImageView alloc] initWithImage:IMAGE(@"消息")];
[rightItem addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(showMessage)] ];
self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:rightItem];

//UINavigationController+FDFullscreenPopGesture源码链接