push隐藏Tabbar，navBar

[self.navigationController setNavigationBarHidden:YES];
self.navigationController.hidesBottomBarWhenPushed = YES; //这句是隐藏tabbar

返回时
先[self.navigationController setNavigationBarHidden:NO];

或在前一页面的viewWillAppear中加入
[self.navigationController setNavigationBarHidden:NO];