ios如何360度旋转控制

Posted 2021-03-31

我想将控制旋转360度。我现在这样做

#define degreesToRadians(x) (M_PI * x / 180.0)

[UIView animateWithDuration:0.25 delay:0.0 options:UIViewAnimationOptionCurveEaseOut animations:^{
    [self.crossButton setTransform:CGAffineTransformRotate(self.crossButton.transform, degreesToRadians(360))];
} completion:nil];

但是没有发生。你知道我做错了什么吗？

答案

360度的旋转变换是身份变换，因此对象根本不是动画。

您可以使用“基本属性动画”实现所需的效果：

[CATransaction begin];
CABasicAnimation *rotationAnimation;
rotationAnimation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.z"];
rotationAnimation.byValue = @(2 * M_PI); // 360 degrees
rotationAnimation.duration = 0.25;
rotationAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseOut];
[self.crossButton.layer addAnimation:rotationAnimation forKey:@"rotationAnimation"];
[CATransaction commit];

更新：如果旋转量不是360度（因此最终位置与初始位置不同），则以下情况应该起作用：

[CATransaction begin];
CGFloat angle = 45.0 * M_PI/180.0;
CABasicAnimation *rotationAnimation;
rotationAnimation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.z"];
rotationAnimation.byValue = @(angle);
rotationAnimation.duration = 0.25;
rotationAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseOut];
rotationAnimation.removedOnCompletion = YES;
[CATransaction setCompletionBlock:^{
    self.crossButton.transform = CGAffineTransformRotate(self.button.transform, angle);
}];
[self.crossButton.layer addAnimation:rotationAnimation forKey:@"rotationAnimation"];
[CATransaction commit];

另一答案

如果旋转360度，则将物体放回相同位置。如果要查看动画，请增加延迟并检查。您将找到整个物体移动以获得完美的圆形。

另一答案

试试下面的代码。

   [UIView animateWithDuration:2.0 delay:0.0 options:UIViewAnimationOptionCurveEaseOut animations:^{

        self.crossButton.transform = CGAffineTransformMakeRotation(M_PI);

    } completion:nil];

另一答案

斯威夫特3：

使用CABasicAnimation

var rotationAnimation = CABasicAnimation()
rotationAnimation = CABasicAnimation.init(keyPath: "transform.rotation.z")
rotationAnimation.toValue = NSNumber(value: (Double.pi * 2.0))
rotationAnimation.duration = 1.0
rotationAnimation.isCumulative = true
rotationAnimation.repeatCount = 100.0
view.layer.add(rotationAnimation, forKey: "rotationAnimation")

这是UIView的扩展函数，用于处理启动和停止旋转操作：

extension UIView {

    func startRotation() {
        let rotation : CABasicAnimation = CABasicAnimation(keyPath: "transform.rotation.z")
        rotation.fromValue = 0
        rotation.toValue = NSNumber(value: Double.pi * 2.0)
        rotation.duration = 1.0
        rotation.isCumulative = true
        rotation.repeatCount = FLT_MAX
        self.layer.add(rotation, forKey: "rotationAnimation")
    }

    func stopRotation() {
        self.layer.removeAnimation(forKey: "rotationAnimation")
    }
}

现在使用，UIView.animation闭包：

UIView.animate(withDuration: 0.5, animations: { 
      button.transform = CGAffineTransform(rotationAngle: (CGFloat(Double.pi)) 
}) { (isHalfAnimationComplete) in
    UIView.animate(withDuration: 0.5) { 
       button.transform = CGAffineTransform(rotationAngle: (CGFloat(Double.pi * 2))
    }    
}