NSValue的使用

1、结构体转换成对象

CALayer的形变就要利用到它

#pragma mark - CALayer的形变




- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{

    /*

     Returns a transform that rotates by 'angle' radians about the vector '(x, y, z)'.

     x 上下旋转；y 左右旋转,z 绕垂直屏幕的方向旋转

     */

    [UIView animateWithDuration:2 animations:^{

        //旋转

        //        [self.imageView.layer setTransform:CATransform3DMakeRotation(M_PI, 1, 1, 0)];//(0,0,1)，（0，0，0）构成一个Z轴的向量

        //收放

        //        [self.imageView.layer setTransform:CATransform3DScale(self.imageView.layer.transform, 0.5, 0.5, 0.5)];

        //平移

//        [self.imageView.layer setTransform:CATransform3DTranslate(self.imageView.layer.transform, 10, 10, 10)];

        //KVC
        [self.imageView.layer setValue:[NSValue valueWithCATransform3D:CATransform3DTranslate(self.imageView.layer.transform, 20, 20, 20)] forKeyPath:@"transform"];
                //[self.imageView.layer setValue:@M_PI forKeyPath:@"transform.rotation"];



    }];
}

transform的属性列表：