How do I spin the CALayer on the current location?

Question

如何在当前位置旋转CALayer？

Answer 1

I used very similar code and it is spinning.

Difference that I assigned radians as float and you are missing assignment for view to display your layer.

- (void)spinLayer:(CALayer*)layer {

    // Create a new spinning animation
    CAAnimation* spinningAnimation = [self animationForSpinning];

    // Assign this animation to the provided layer's opacity attribute.
    // Any subsequent change to the layer's opacity will
    // trigger the animation.
    [layer addAnimation:spinningAnimation forKey:@"opacity"];

    // So let's trigger it now
    layer.opacity = 0.99;
[self.contentView.layer addSublayer:layer];
}