Query PFFile from the pre-defined User class with Parse - ios

Question

I think it's very trivial, but i can't figure it out why these codes are incorrect.
I want to retrieve one image from the Parse User class. I mean, every user has a profile picture, that i store under the "imageFile" column and i would like to load it to a PFImageView. The upload works correctly, but i'cant retrieve it. The log says error, because there is no matches for the query. The file what i want to retrieve exists, so it's 100% that my query implementation is wrong. I would really appreciate any relevant help, thanks.
Non query version: (all versions are implemented in the viewDidLoad)
self.userThumbnail.file = self.currentUser.imageFile;
[self.userThumbnail loadInBackground];
query version
PFQuery *queryImage = [PFQuery queryWithClassName:#"User"];
[queryImage whereKey:#"imageFile" equalTo:self.currentUser]
[queryImage getFirstObjectInBackgroundWithBlock:^(PFObject *object, NSError *error) {
if (error) {
NSLog(#"ERROR");
} else {
PFFile *file = [object objectForKey:#"imageFile"];
self.userThumbnail.file = file;
[self.userThumbnail loadInBackground];
}
}];
query version
PFQuery *queryImage = [PFUser query];
[queryImage whereKey:#"imageFile" equalTo:self.currentUser];
[queryImage getFirstObjectInBackgroundWithBlock:^(PFObject *object, NSError *error) {
if (error) {
NSLog(#"ERROR");
} else {
PFFile *file = [object objectForKey:#"imageFile"];
self.userThumbnail.file = file;
[self.userThumbnail loadInBackground];
}
}];

Answer 1

This line:
[queryImage whereKey:#"imageFile" equalTo:self.currentUser];
looks like a mistake. It says, "find Users whose imageFile column (presumably a PFImage) is equal to the current user object". That will never be true.
Try to separate the logic for finding a user from dealing with it's imageFile. In other words. First get a user:
PFQuery *queryUser = [PFQuery queryWithClassName:#"User"];
[queryUser whereKey:#"username" equalTo:#"some-user-name"];
[queryUser getFirstObjectInBackgroundWithBlock:^(PFObject *user, NSError *error) {}];
// or maybe instead of username==, get a user with their id ...
[queryUser getObjectInBackgroundWithId:#"some-user-id" block:^(PFObject *user, NSError *error) {}];
Now, inside the completion block for querying a user, do your file logic:
[queryUser getFirstObjectInBackgroundWithBlock:^(PFObject *user, NSError *error) {
PFFile *userImageFile = user[#"imageFile"];
[userImageFile getDataInBackgroundWithBlock:^(NSData *imageData, NSError *error) {
if (!error) {
UIImage *image = [UIImage imageWithData:imageData];
// this is a regular UIImage now, put it in your UI
self.someUIImageView.image = image;
}
}];
}];