ios8 push无缝隐藏navibar和statusbar

如下代码效果不错：

- (void)viewWillAppear:(BOOL)animated{
    [super viewWillAppear:animated];
    
    [self.navigationController setNavigationBarHidden:YES animated:YES];
    
}

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

- (void)viewDidAppear:(BOOL)animated{
    [super viewDidAppear:animated];
    [[UIApplication sharedApplication] setStatusBarHidden:YES withAnimation:UIStatusBarAnimationFade];
    
}

别忘了把info.plist中增加一项：View controller-based status bar appearance，并且把值设置为NO。如果设置为YES，则在controller中用回调方法去掉statusbar，但是效果好像不太好，希望各位指正啊！

- (BOOL)prefersStatusBarHidden{
    return YES;//隐藏
}

[self setNeedsStatusBarAppearanceUpdate];//刷新statusbar状态