用图像将Facebook打开图形故事发布到Facebook

Question

我正试图在iOS上向Facebook发布OpenGraph故事。我一直在关注这个教程。

https://developers.facebook.com/docs/ios/open-graph/

我也一直在推荐

https://github.com/fbsamples/ios-howtos/blob/master/FBOGSampleSD/FBOGSampleSD/OGShareViewController.m

我可以将帖子上传到FB，但图片丢失了。我尝试了几种变体，但发现文档很稀疏。任何见解将不胜感激：

UIImage *loadedImage = [UIImage imageWithContentsOfFile:file];

NSArray* image = @[@{@"url":loadedImage, @"user_generated": @"true"}];


id<FBGraphObject> objectname =
[FBGraphObject openGraphObjectForPostWithType:@"namespacename:objectname"
                                        title:@"objectname"
                                        image:nil
                                          url:nil
                                  description:@"description"];

id<FBOpenGraphAction> actionname = (id<FBOpenGraphAction>)[FBGraphObject graphObject];

[actionname setObject:image forKey:@"image"];
[actionname setObject:objectname forKey:@"objectname"];


// Check if the Facebook app is installed and we can present the share dialog
FBOpenGraphActionParams *params = [[FBOpenGraphActionParams alloc] init];
params.action = actionname;
params.actionType = @"namespacename:objectname";

// If the Facebook app is installed and we can present the share dialog
if ([FBDialogs canPresentShareDialogWithOpenGraphActionParams:params]) {

     [FBDialogs presentShareDialogWithOpenGraphAction:actionname
                                            actionType:@"namespacename:actionname"
                                 previewPropertyName:@"objectname"
                                               handler:^(FBAppCall *call, NSDictionary *results, NSError *error) {
                                                 if(error) {
                                                     // There was an error
                                                        NSLog(@"Error publishing story: %@", error.description);
                                                 } else {
                                                     // Success
                                                     NSLog(@"result %@", results);
                                                 }
                                             }];
} else {
     NSLog(@"cant show the share dialog ");
}

我已经彻底检查了代码，我发现的唯一区别是，我不是从图库中选择图像，而是从文件中加载它。正如我所提到的那样，帖子经过并在Facebook上共享，但图片不会出现在Feed或新闻Feed上的可点击对象中。当共享对话框加载时，我可以看到图像的缩略图，所以我相信它正在加载正常。任何帮助，将不胜感激。提前谢谢。