ios – 想要随时间改变UIView背景颜色

非常简单,我只想根据一天中的时间更改backgroundView的颜色,但由于某种原因它不起作用.任何帮助都会很棒.

@IBOutlet weak var backgroundView: UIView!

override func viewDidLoad() {
    super.viewDidLoad()

    let darkColor=UIColor(red: 51, green: 52, blue: 50, alpha: 1.0)
    let greyColor=UIColor(red: 238, green: 240, blue: 239, alpha: 1.0)
    let hour = NSCalendar.current.component(.hour, from: NSDate() as Date)

    switch hour {
        case 1..<6: self.backgroundView.backgroundColor = darkColor
           break
        case 7..<18: self.backgroundView.backgroundColor = greyColor
           break
        case 19..<24: self.backgroundView.backgroundColor = darkColor
           break
    default:self.backgroundView.backgroundColor = greyColor
    }
}

问题是以下几行分别忽略6,18,24：

1..<6 //1 - 5

7..<18 //7 - 17

19..<24 //19 - 23

根据您的时间,检查时间;如果它恰好落在6号,18号,24号,那么它可能就是你认为它不起作用的原因.

使用您的代码,我确认视图的backgroundColor确实发生了变化.

尝试将代码更改为以下内容：

switch hour
{
     // hours 1 to 6
     case 1...6: self.backgroundView.backgroundColor = darkColor
            break
     // hours 7 to 18
     case 7...18: self.backgroundView.backgroundColor = greyColor
            break
     //hours 19 to 23 and 0
     case 19...23, 0: self.backgroundView.backgroundColor = darkColor
            break
     default:self.backgroundView.backgroundColor = greyColor
}

另一个问题如下：

let darkColor=UIColor(red: 51, green: 52, blue: 50, alpha: 1.0)

let greyColor=UIColor(red: 238, green: 240, blue: 239, alpha: 1.0)

因为他们应该：

let darkColor = UIColor(red: 51/255, green: 52/255, blue: 50/255, alpha: 1.0)

let greyColor = UIColor(red: 238/255, green: 240/255, blue: 239/255, alpha: 1.0)