ios - 我如何继续旋转图像，直到服务器快速响应

Question

每当单击按钮时，我都会进行异步调用，现在我想要一个像刷新图标一样的图像旋转或旋转，直到我收到服务器的响应。我现在所拥有的只是将 pi 旋转 180，并且当响应到达时图像也不会重置。下面粘贴了我的示例代码:

//When the update button is clicked
@objc func updateHome(){
    UIView.animate(withDuration: 1) {
        self.updateIcon.transform = CGAffineTransform(rotationAngle: .pi)
    }
    getBalances()
}
//Inside getBalances function
DispatchQueue.main.async {
                        if responseCode == 0 {
                            let today = self.getTodayString()
                            print("Time: \(today)")
                            UIView.animate(withDuration: 1) {
                                self.updateIcon.transform = CGAffineTransform(rotationAngle: .pi)
                            }
}

Answer 1

此代码使用 CABasicAnimation 无限期地旋转您的 UIImageView:

let rotateAnimation = CABasicAnimation(keyPath: "transform.rotation")
rotateAnimation.fromValue = 0.0
rotateAnimation.toValue = CGFloat(.pi * 2.0)
rotateAnimation.duration = 1.0  // Change this to change how many seconds a rotation takes
rotateAnimation.repeatCount = Float.greatestFiniteMagnitude

updateIcon.layer.add(rotateAnimation, forKey: "rotate")

当您从服务器收到信号时，您可以调用

updateIcon.layer.removeAnimation(forKey: "rotate")

停止动画