[Facebook iOS SDK example] Publish an Open Graph (OG) story that: 1/ uses image staging 2/ creates a custom, user-owned OG object 3/ creates a custom OG action

gistfile1.m

    UIImage* image = [UIImage imageNamed:@"inspiration-2.jpg"]; // image stored in app's resources

    // stage an image
    [FBRequestConnection startForUploadStagingResourceWithImage:image
                                              completionHandler:^(FBRequestConnection *connection, id result, NSError *error) {
        if(error) {
            NSLog(@"Error staging resource.\n%@", error);
            
            int code = [[[[[error userInfo] objectForKey:@"com.facebook.sdk:ParsedJSONResponseKey"] objectForKey:@"body"] objectForKey:@"error"] objectForKey:@"code"];
            if(code == 2500) {
                NSLog(@"...couldn't find an access token.  Gotta log in to post stories via the API.");
            }
        } else {
            NSLog(@"Successfuly staged image with staged URI: %@", [result objectForKey:@"uri"]);
            
            NSString* stagedImageId = [result objectForKey:@"uri"];
            NSLog(@"Staged Image URI: %@", stagedImageId);
            
            // configure custom, user-owned object.  default audience == $app-ceiling.
            NSMutableDictionary<FBOpenGraphObject> *object = [FBGraphObject openGraphObjectForPost];
            object.provisionedForPost = YES;
            object[@"title"] = @"Inspiration";
            object[@"type"] = @"fbsdktoolkit:route";
            object[@"description"] = @"Mazama Inspiration route on Goat Wall";
            object[@"image"] = @[
                                 @{@"url": stagedImageId, @"user_generated" : @"true" }
                                ];
            
            // post the object
            [FBRequestConnection startForPostOpenGraphObject:object
                                           completionHandler:^(FBRequestConnection *connection, id result, NSError *error) {
                                               if(error) {
                                                   NSLog(@"Error: %@", error);
                                               } else {
                                                   NSLog(@"Success.  %@", result);
                                               }
                                               
                                               NSString* objectId = [result objectForKey:@"id"]; // read object ID from previous response
                                               id<FBOpenGraphAction> action = (id<FBOpenGraphAction>)[FBGraphObject graphObject];
                                               [action setObject:objectId forKey:@"route"];
                                               
                                               // create action referencing user owned object.  default audience == $app-ceiling
                                               [FBRequestConnection startForPostWithGraphPath:@"/me/fbsdktoolkit:climb"
                                                                                  graphObject:action
                                                                            completionHandler:^(FBRequestConnection *connection, id result, NSError *error) {
                                                                                if(error) {
                                                                                    NSLog(@"Error: %@", error);
                                                                                } else {
                                                                                    NSLog(@"Success.  Created action with ID: %@", [result objectForKey:@"id"]);
                                                                                    NSLog(@"See the story at: https://www.facebook.com/{your-vanity-url}/activity/%@", [result objectForKey:@"id"]);
                                                                                }
                                                                            }];
                                           }];
        }
    }];

@balazsnemeth Not sure if you figured it out. But from this stackoverflow answer, you can do this after line 20:

[object setObject: @"true" forKey: @"fb:explicitly_shared"];