Retrieving Images from Parse.com database on android but it returns null

Question

On Parse.com, I have a class named ImagesEntry with a column named ImageFile that has images saved.

I have this code on android to read every row and return the images but it returns null.

    ParseFile[] getImagesFromParseCloudDB() {                

            ParseQuery<ParseObject> query = new ParseQuery<ParseObject>(
                    "ImagesEntry");

            query.orderByDescending("_created_at");
            try {
                ob = query.find(); // 'List<ParseObject> ob' initialzed above OnCreate
            } catch (ParseException e) {
                Log.e("Error", e.getMessage());
                e.printStackTrace();
            }

            int i = 0;

            for (ParseObject images : ob) {
                // imagesFromDB is an array of type 'ParseFile'                
                imagesFromDB[i] = (ParseFile)images.getParseFile("ImageFile");
                i++;        
            }

            return imagesFromDB;
        }

Any pointers on what wrong am I doing ?

Oleg Osipenko · Accepted Answer · 2015-06-10 11:14:13Z

1

I think the reason for this is that getParseFile() doesn't request actual file. According to docs

function will not perform a network request

You need to add call ParseFile.getDataInBackground() or ParseFile.getData() to get actual data of the file. But don't try to spawn too many background loading tasks while iterating through array - you'll get exception if your array's size would larger than PoolSize of ExecutorService used by Parse. Consider creating some background task and synchronous execution of getData() request or customizing ExecutorService for Parse.

answered Jun 10, 2015 at 11:14

Oleg Osipenko

2,4301 gold badge22 silver badges28 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Jose Luis Martinez · Accepted Answer · 2015-06-12 11:01:28Z

First of all, this string "_created_at" is wrong for me. In my app I have "createdAt" and works fine.

I recommend you first get all ID in a List and use my code (it works for me):

ParseQuery query = new ParseQuery("Your_class_name");
                    query.getInBackground(imagenID, new GetCallback() {
                        @Override
                        public void done(ParseObject parseObject, ParseException e) {

                        }

                        @Override
                        public void done(Object o, Throwable throwable) {
                            ParseObject object = (ParseObject) o;
                            ParseFile foto = (ParseFile) object.get("Your_column_name");
                            foto.getDataInBackground(new GetDataCallback() {
                                @Override
                                public void done(byte[] bytes, ParseException e) {
                                    if (e == null) {
                                        //do things with this bytes
                                    } else {
                                        Toast.makeText(getApplicationContext(), "Error al descargar la foto", Toast.LENGTH_SHORT).show();
                                        e.printStackTrace();
                                    }
                                }
                            });

                        }
                    });
                }

Collectives™ on Stack Overflow

Retrieving Images from Parse.com database on android but it returns null

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related