swift - UIView 的动画颜色

Question

我使用 Swift 2 和 Xcode 7.1

我想知道如何执行嵌套动画？其实我想要的动画会逐渐改变我视线的颜色。 View 将:红色 -> 蓝色 -> 绿色 -> 红色 -> ...

这是我的代码:

func animate(){
    UIView.animateWithDuration(1.0, animations: {
        //self.lbl.transform = CGAffineTransformMakeRotation(0.5)
        self.circle.backgroundColor = UIColor(red: 0.93, green: 0.89, blue: 0.27, alpha: 1)
        }, completion: {
            (value: Bool) in
            UIView.animateWithDuration(1.0, animations: {
                //self.lbl.transform = CGAffineTransformMakeRotation(0.5)
                self.circle.backgroundColor = UIColor(red: 0.3, green: 0.2, blue: 0.7, alpha: 1)
                }, completion: {
                    (value: Bool) in
                    self.animate()
            })
    })
}

Answer 1

对于嵌套动画，您应该使用 UIView.animateWithDuration 的选项，它们是 Repeat，在本例中是 Autoreverse

  UIView.animateWithDuration(2.0, delay:0, options: [.Repeat, .Autoreverse], animations: {

           //execute animation changes hear

            }, completion: nil)