iOS 监听用户截屏并获取截屏图片（动态页面）

最近有个需要，需要截取用户当前的页面，但是一般常见的方法只能截取静态页面，动态页面会导致黑屏(如视频)，如果先监听用户的截屏，再拿到截屏图片就能避免这个问题，正确姿势如下：
1，添加截屏通知监听

//引用框架
#import <Photos/Photos.h>
//注册通知
[[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(userDidTakeScreenshot:)
                                                 name:UIApplicationUserDidTakeScreenshotNotification object:nil];

2，截屏响应

//截屏响应
- (void)userDidTakeScreenshot:(NSNotification *)notification
{
    NSLog(@"检测到截屏");
    //由于截屏之后图片不会立即存储到相册，所以需要延迟一些时间再做处理
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(3 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{

        PHAsset * asset = [self latestAsset];
        PHImageManager * imageManager = [PHImageManager defaultManager];
         [imageManager requestImageDataForAsset:asset options:nil resultHandler:^(NSData * _Nullable imageData, NSString * _Nullable dataUTI, UIImageOrientation orientation, NSDictionary * _Nullable info) {
                
                    UIImage * image = [UIImage imageWithData:imageData];
                    [self addVideoTaskWithImage:image];
                    self.isJiePing = NO;
        }];
                        
    });
}

精华：监听用户截屏后，获取相册最新图片
ps:调用之前需要用户同意完全访问相册权限

//获取最新图片
- (PHAsset *)latestAsset {
    // 获取所有资源的集合，并按资源的创建时间排序
    PHFetchOptions *options = [[PHFetchOptions alloc] init];
    options.sortDescriptors = @[[NSSortDescriptor sortDescriptorWithKey:@"creationDate" ascending:NO]];
    PHFetchResult *assetsFetchResults = [PHAsset fetchAssetsWithOptions:options];
    return [assetsFetchResults firstObject];
}

//判断相册权限
    PHAuthorizationStatus status = [PHPhotoLibrary authorizationStatus];
    if (status == PHAuthorizationStatusAuthorized ) {

    }