怎样隐藏导航状态栏NavigationBar

//怎样隐藏导航状态栏NavigationBar

- (void)viewWillAppear:(BOOL)animated

{
    [super viewWillAppear:animated];
    [[UIApplication sharedApplication] setStatusBarHidden:YES withAnimation:UIStatusBarAnimationNone];
    [self.navigationController setNavigationBarHidden:YES animated:NO];
}

-(void)viewWillDisappear:(BOOL)animated
{
    [super viewWillDisappear:animated];
    [[UIApplication sharedApplication] setStatusBarHidden:NO withAnimation:UIStatusBarAnimationNone];
    [self.navigationController setNavigationBarHidden:NO animated:NO];
}
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