Question

我有一个包含几个字段的主题类。

背景颜色，字体颜色和元素颜色。

这个类也没有那些

的静态变体

class Themes {
    static let defaultTheme = Themes(topColor: "5856D6",bottomColor: "C644FC",elementColor: "1F1F21",fontColor: "2B2B2B", name:"one")
    static let defaultTheme1 = Themes(topColor: "5AD427",bottomColor: "FFDB4C",elementColor: "1F1F21",fontColor: "2B2B2B", name:"two")
    static let defaultTheme2 = Themes(topColor: "FB2B69",bottomColor: "FF5B37",elementColor: "1F1F21",fontColor: "2B2B2B", name:"three")
    static let defaultTheme3 = Themes(topColor: "52EDC7",bottomColor: "5AC8FB",elementColor: "1F1F21",fontColor: "2B2B2B", name:"four")
    static let defaultTheme4 = Themes(topColor: "5AD427",bottomColor: "FFDB4C",elementColor: "1F1F21",fontColor: "2B2B2B", name:"five")

    let topColor:UIColor
    let bottomColor:UIColor
    let elementColor:UIColor
    let fontColor:UIColor
}

我的视图控制器默认加载第一个。

override func viewDidLoad() {
    super.viewDidLoad()
    self.initView(ThemeManagement.sharedInstance.getTheme())

}

我有一个按钮可以更改主题，方法是转到next其中一个默认值，并在defaultTheme

后循环回defaultTheme4

原始运行在initView内部正在正确设置视图。但每次传递都不会更新视图。尽管正在打印函数的日志消息。

func initView(objectColor : Themes){
    println("initing theme "+objectColor.name+"\n"+objectColor.topColor.debugDescription)
    let background = CAGradientLayer().gradient(objectColor.topColor, bottomColorCode: objectColor.bottomColor)
    background.frame = self.view.bounds
    self.view.layer.insertSublayer(background, atIndex: 0)


    codes.delegate = self
    codes.placeholder = "####"
    codes.textAlignment = NSTextAlignment.Center
    codes.font = Themes.defaultThemeWithFontSize(.H2)
    codes.textColor = objectColor.fontColor

    segments.tintColor = objectColor.elementColor

    segments.setTitle(String.fontAwesomeIconWithName(.Male), forSegmentAtIndex: 0)
    segments.setTitle(String.fontAwesomeIconWithName(.VenusMars), forSegmentAtIndex: 1)
    segments.setTitle(String.fontAwesomeIconWithName(.Female), forSegmentAtIndex: 2)
    var font = UIFont.fontAwesomeOfSize(fontsize/2);
    var attr = NSDictionary(object: font, forKey: NSFontAttributeName)
    segments.setTitleTextAttributes(attr as [NSObject : AnyObject], forState:UIControlState.Normal)

    acceptButton.titleLabel?.font = UIFont.fontAwesomeOfSize(fontsize)
    acceptButton.setTitle(String.fontAwesomeIconWithName(FontAwesome.ArrowCircleORight), forState: .Normal)
    acceptButton.tintColor = UIColor.greenColor()

    workedButton.setTitle("yes", forState: UIControlState.Normal)
    workedButton.tintColor = objectColor.fontColor
    workedButton.layer.cornerRadius = 5
    workedButton.titleLabel?.font = Themes.defaultThemeWithFontSize(.H2)
    workedButton.backgroundColor = UIColor(red:0.333, green:0.937, blue:0.796, alpha: 0.2)

    didntWorkButton.setTitle("no", forState: UIControlState.Normal)
    didntWorkButton.tintColor = objectColor.fontColor
    didntWorkButton.layer.cornerRadius = 5
    didntWorkButton.titleLabel?.font = Themes.defaultThemeWithFontSize(.H2)
    didntWorkButton.backgroundColor = UIColor(red:0.333, green:0.937, blue:0.796, alpha: 0.2)


    locationButton.setTitle("Current Location", forState: UIControlState.Normal)
    locationButton.tintColor = objectColor.fontColor
    locationButton.layer.cornerRadius = 5
    locationButton.titleLabel?.font = Themes.defaultThemeWithFontSize(.H3)

    didItWork.text = "Did it work?"
    didItWork.font = Themes.defaultThemeWithFontSize(.H2)
    didItWork.textColor = objectColor.fontColor

    self.view.setNeedsDisplay()
}

我是否必须执行其他操作才能更新背景layer并更改字体颜色？

Answer 1

由此

self.view.layer.insertSublayer(background, atIndex: 0)

每次在新的背景图层后面插入旧的背景图层时，您都不会看到它。

并更改视图的tintColor不会立即更改视图的颜色，因此请尝试更改它的textColor direacly

通过cripto编辑

上面的答案是正确的。我只想添加我的解决方案。

我只是保留对图层的引用并删除它，只要它不为null。这保证了我可以在第一次通过时设置它并在每次之后更改它。

    if((backgroundLayer) != nil){
        backgroundLayer.removeFromSuperlayer()

    }
    backgroundLayer = CAGradientLayer().gradient(objectColor.topColor, bottomColorCode: objectColor.bottomColor)
    backgroundLayer.frame = self.view.bounds
    self.view.layer.insertSublayer(backgroundLayer, atIndex: 0)

Swift重绘视图

1 个答案: