ios UINavgationBar隐藏

1、

-(void)viewWillAppear:(BOOL)animated{

[super viewWillAppear:YES];

[self.navigationController.view sendSubviewToBack:self.navigationController.navigationBar];

}

-(void)viewWillDisappear:(BOOL)animated{

[super viewWillDisappear:YES];

[self.navigationController.view bringSubviewToFront:self.navigationController.navigationBar];

}