刷新导航栏背景色

导航栏与ViewController中的不同之处在于,导航栏是半透明的,系统将为导航栏应用默认的alpha值。

self.navigationController?.navigationBar.isTranslucent = false
self.navigationController?.navigationBar.barTintColor = UIColor(red: 104.0/255.0, green: 154.0/255.0, blue: 26.0/255.0, alpha: 1.0)

或手动:

导航栏和ViewController背景颜色的差异为20。这使UINavigationBar具有“光泽”外观,因此具有内置样式。

因此,R=104 | G=154 | B=26将变为R=84 | G=134 B | B=6。

navigationController?.navigationBar.barTintColor = UIColor(red: 84.0/255.0, green: 134.0/255.0, blue: 6.0/255.0, alpha: 1.0)
self.view.backgroundColor = UIColor(red: 104.0/255.0, green: 154.0/255.0, blue: 26.0/255.0, alpha: 26.0)

有两种方法:

1) 将导航栏设置为非半透明:

navigationController?.navigationBar.barTintColor = UIColor(red: 1.0, green: 0, blue: 0, alpha: 1.0)
navigationController?.navigationBar.isTranslucent = false

2) 设置导航栏的背景图像:

navigationController?.navigationBar.setBackgroundImage(UIImage(named: "red"), for: .default)

您还可以使用以下函数提供基于UIColor生成的UIImage:

func convertUIColorToUIImage(_ color: UIColor, size: CGSize) -> UIImage {
    let rect = CGRect(x: 0, y: 0, width: size.width, height: size.height)
    UIGraphicsBeginImageContextWithOptions(size, false, 0)
    color.setFill()
    UIRectFill(rect)
    let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
    UIGraphicsEndImageContext()
    return image
}