核心动画-翻页效果的实现

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
    self.imageView.image = [UIImage imageNamed:[NSString stringWithFormat:@"%i.jpg", _imageIndex]];
    _imageIndex++;
    if (_imageIndex > 9) {
        _imageIndex = 1;
    }
    
    CATransition *anim = [CATransition animation];
    // 动画类型
    anim.type = @"pageCurl";
    // 过渡方向
    anim.subtype = kCATransitionFromRight;
// 动画延迟
    anim.duration = 0.5;
// 添加动画
    [self.view.layer addAnimation:anim forKey:nil];
}