实现隐藏tabbar
若有：页面A有tabbar，跳转到页面B的时候隐藏toolbar，再点击返回页面A，显示tabbar实现
页面A:
-(void)viewWillAppear:(BOOL)animated{
self.tabBarController.tabBar.hidden = NO;
}
页面B：
-(void)viewWillAppear:(BOOL)animated{
self.tabBarController.tabBar.hidden = YES;
UIImageView *image = (UIImageView *)[self.tabBarController.viewviewWithTag:100];
image.hidden =YES;
}
-(void)viewWillDisappear:(BOOL)animated{
[super viewWillDisappear:animated];
self.tabBarController.hidesBottomBarWhenPushed = NO;
}
