Question

好吧，我在使用CAGradientLayer快速制作的动画颜色渐变时出现问题 -

动画来自这两个颜色数组：

Self.gradient.colors = [colorWithHexString("#4342F9").CGColor, colorWithHexString("#A442F9").CGColor, UIColor.magentaColor().CGColor] //start
        self.toColors = [colorWithHexString("#FB22B5").CGColor, colorWithHexString("#FB258F").CGColor,colorWithHexString("#FD5E50").CGColor,colorWithHexString("#FD963C").CGColor] //end

渐变动画效果很好，直到动画结束并需要循环。这是完整的动画：

override func viewDidAppear(animated: Bool) {

        self.gradient = CAGradientLayer()
        self.gradient.frame = self.view.bounds

        self.gradient.colors = [colorWithHexString("#4342F9").CGColor, colorWithHexString("#A442F9").CGColor, UIColor.magentaColor().CGColor] //start
        self.toColors = [colorWithHexString("#FB22B5").CGColor, colorWithHexString("#FB258F").CGColor,colorWithHexString("#FD5E50").CGColor,colorWithHexString("#FD963C").CGColor] //end

        //self.gradient.colors = [colorWithHexString("#6442F9").CGColor, colorWithHexString("#6442F9").CGColor]
        //self.toColors = [colorWithHexString("#FB863F").CGColor, colorWithHexString("#FB863F").CGColor]
        self.view.layer.insertSublayer(self.gradient, atIndex: 0)

        animateLayer()
    }    

func animateLayer(){

        self.fromColors = self.gradient.colors
        self.gradient.colors = self.toColors! as! [AnyObject] // You missed this line
        var animation : CABasicAnimation = CABasicAnimation(keyPath: "colors")
        animation.delegate = self
        animation.fromValue = fromColors
        animation.toValue = toColors
        animation.duration = 10.00
        animation.removedOnCompletion = true
        animation.fillMode = kCAFillModeForwards
        animation.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionLinear)
        animation.delegate = self

        self.gradient.addAnimation(animation, forKey:"animateGradient")
    }

    override func animationDidStop(anim: CAAnimation!, finished flag: Bool) {

        self.toColors = self.fromColors;
        self.fromColors = self.gradient.colors

        animateLayer()
    }

完成循环后，渐变“跳过”意味着它不会从较暗的渐变颜色渐变到较浅的渐变颜色，因为它会反向旋转。它只是“翻转”。

为什么这样做？如何在animationDidStop中循环后使其淡出？

Swift：CAGradientLayer的动画在动画结束时跳过/不淡化？

0 个答案: