Question

我是新手解析并尝试创建一个将用户链接到他/她的照片的PFRelation。这是我的代码：

NSData *imageData = UIImagePNGRepresentation(myImage);
PFFile *imageFile = [PFFile fileWithName:@"image.png" data:imageData];
PFObject *pic = [PFObject objectWithClassName:@"Pics"];
//[pic setObject:imageFile forKey:@"Image"];
pic[@"Image"] = imageFile;
PFUser *user = [PFUser currentUser];
PFRelation *relation = [user relationForKey:@"myPhotos"];
[relation addObject:pic];
[user saveInBackground];
//[pic saveInBackground];


NSString * storyboardName = @"Main";
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:storyboardName bundle: nil];
UIViewController *myViewController = [storyboard instantiateViewControllerWithIdentifier:@"MainScreen"];
[self presentViewController:myViewController animated:YES completion:nil];

我知道图片本身正在保存，因为当我让图片保存在后台时，当我点击Pic类时，它会显示我拍摄的图片。但是，我的问题是，当我查看User类时，当我点击myPhotos关系时，没有任何对象处于该关系中。为什么我的图像不会被添加到关系中？

Answer 1

PFObject *details = [PFObject objectWithClassName:@"**your table name**"];

NSData *imageData = UIImagePNGRepresentation(myImage);

PFObject *picDetails = [PFObject objectWithClassName:@"**myphotos**”];

picDetails [@"picture"] = [UIImage imagewithdata:imageData];
                     [Details save];  [picDetails save];
                          FRelation *relation = [Details relationForKey:@"**myphotos**"];  [relation addObject:details];
                            [Details saveInBackgroundWithBlock:^(BOOL succeeded, NSError *error) {
                                //Do something after the last save...

                                if (succeeded) {
                                    // The object has been saved.
                                    UIAlertView *success_alert = [[UIAlertView alloc]initWithTitle:@"Success" message:@"Successfully image saved" delegate:self cancelButtonTitle:@"OK" otherButtonTitles: nil];
                                    [success_alert show];

                                } else {
                                    // There was a problem, check error.description
                                    UIAlertView *fail_alert = [[UIAlertView alloc]initWithTitle:@"Failed" message:@"Failed to save data" delegate:self cancelButtonTitle:@"OK" otherButtonTitles: nil];
                                    [fail_alert show];
                                }
                            }];

这是使用图像保存存储在PFRelation中的方法。我希望这回答可能对你有所帮助。谢谢。

iPhone - PFRelation不保存对象

1 个答案: