ios - Facebook iOS SDK - 将自定义操作和对象发布到用户活动源

Question

我有以下代码应该向当前用户的提要添加一个对象

id<FBOpenGraphAction> object = (id<FBOpenGraphAction>)[FBGraphObject graphObject];
            [object setObject:@"namespace:objectName" forKey:@"type"];
            [object setObject:@"Object Title" forKey:@"title"];

            [FBRequestConnection startForPostWithGraphPath:@"me/namespace:actionName"
                                               graphObject:object
                                         completionHandler:^(FBRequestConnection *connection, id result, NSError *error) {
                                             if (error) {
                                                 NSLog(@"Error: %@", error.userInfo);
                                             } else {
                                                 NSLog(@"Success!!");
                                             }
                                         }];

但是，我收到以下错误：

2013-06-18 23:12:31.846 Events[707:60b] Error: {
    "com.facebook.sdk:ErrorSessionKey" = "<FBSession: 0x14ff95a0, state: FBSessionStateOpen, loginHandler: 0x14dde700, appID: 474218799329968, urlSchemeSuffix: , tokenCachingStrategy:<FBSessionTokenCachingStrategy: 0x14dde850>, expirationDate: 4001-01-01 00:00:00 +0000, refreshDate: 2013-06-18 22:12:06 +0000, attemptedRefreshDate: 0001-12-30 00:00:00 +0000, permissions:(\n    \"basic_info\"\n)>";
    "com.facebook.sdk:HTTPStatusCode" = 500;
    "com.facebook.sdk:ParsedJSONResponseKey" =     {
        body =         {
            error =             {
                code = 1611072;
                message = "The action you're trying to publish is invalid because it does not specify any reference objects. At least one of the following properties must be specified: event.";
                type = Exception;
            };
        };
        code = 500;
    };
}