1, 页面加载完毕即将显示时, 保存当前NavigationBar及其分割线的背景图片, 并分别设置其背景图片为新创建空白图片
overridefuncviewWillAppear(_animated:Bool) {
super.viewWillAppear(animated)
naviBarBgImage = navigationController?.navigationBar.backgroundImage(for: .default)
navigationController?.navigationBar.setBackgroundImage(UIImage(), for: .default)
naviBarBgShadowImage = navigationController?.navigationBar.shadowImage
navigationController?.navigationBar.shadowImage = UIImage()
}
2, 在页面即将消失时, 还原其背景图片
overridefuncviewWillDisappear(_animated:Bool) {
super.viewWillDisappear(animated)
navigationController?.navigationBar.setBackgroundImage(naviBarBgImage, for: .default)
navigationController?.navigationBar.shadowImage = naviBarBgShadowImage
}
