DFImageActivityItemProvider draft

gistfile1.m

@interface DFImageActivityItemProvider : UIActivityItemProvider

- (instancetype)initWithPlaceholderItem:(id)placeholderItem request:(DFImageRequest *)request;

@end

@implementation DFImageActivityItemProvider {
    DFImageRequest *_request;
    DFImageRequestID *_requestID;
}

- (instancetype)initWithPlaceholderItem:(id)placeholderItem request:(DFImageRequest *)request {
    if (self = [super init]) {
        _request = request;
    }
    return self;
}

- (id)activityViewControllerPlaceholderItem:(UIActivityViewController *)activityViewController {
    return [UIImage new];
}

- (id)item {
    dispatch_semaphore_t sema = dispatch_semaphore_create(0);
    UIImage *__block image;
    _requestID = [[DFImageManager sharedManager] requestImageForRequest:_request completion:^(UIImage *image, NSDictionary *info) {
        image = image;
        dispatch_semaphore_signal(sema);
    }];
    dispatch_semaphore_wait(sema, DISPATCH_TIME_FOREVER);
    return image;
}

- (void)cancel {
    [super cancel];
    [_requestID cancel];
}

@end