- (void)viewDidLoad {
  [super viewDidLoad];
  // Do any additional setup after loading the view.
  self.view.backgroundColor = [UIColor blackColor];
  if (@available(iOS 11, *)) {
    [self setAdditionalSafeAreaInsets:self.view.safeAreaInsets];
  }
  [self defaultUI];
  [self addNotification];
}
//iOS11新增，安全區域發生改變時調用
- (void)viewSafeAreaInsetsDidChange{
  [super viewSafeAreaInsetsDidChange];
  [self defaultUIWithSafeAreaInsets:self.view.safeAreaInsets];
}