1.重写系统的push的方法

-(void)pushViewController:(UIViewController*)viewController animated:(BOOL)animated{

if(self.viewControllers.count) {

viewController.hidesBottomBarWhenPushed=YES;

}

[superpushViewController:viewControlleranimated:animated];

}

2.修改tabbarControler的tabor的hidden属性

-(void)viewWillAppear:(BOOL)animated{

self.tabBarController.tabBar.hidden=NO;

}

3.修改tabbarControler的tabbar的frame

-(void)viewWillAppear:(BOOL)animated{

CGRectchange =self.tabBarController.tabBar.frame;

change.origin.y = 0;

self.tabBarController.tabBar.frame= change;

}