导航栏貌似无法隐藏？

[lusen.bei]

调用以下函数，只是让导航栏变透明而已，无法起到隐藏的效果。

Calling the following function just makes the navigation bar transparent and cannot hide it.

override func viewDidLoad() {
super.viewDidLoad()
wx_navigationBar.isHidden = true
}