Getting data out of a inner class

Question

I've been getting really frustrated with an issue. How do I access the data that I get in a inner class. I'm using Parse for the back end of my new application but all parse methods are used anonymously and are inner classes so I can't really access anything that is retrieved. Is there a way around it?

I tried this and it didn't work. Everything needs to be final and finals can not be altered within the inner class.

Here's my code.

 imageView_intro = (ImageView)findViewById(R.id.imageView_intro);
    List<Bitmap> list = new ArrayList<Bitmap>();
   BackEndUtils.downloadIntroImage(list);
    imageView_intro.setImageBitmap(list.get(0));

public static void  downloadIntroImage(final List<Bitmap> list){
    ParseQuery query = new ParseQuery("Intro");
    query.whereEqualTo("name","intro");

    //BEUFindCallBack beuFindCallBack = new BEUFindCallBack("image");
    query.findInBackground(new FindCallback<ParseObject> (){

        @Override
        public void done(List<ParseObject> parseObjects, com.parse.ParseException e) {
            for(ParseObject tempObject: parseObjects){
                ParseFile tempFile = (ParseFile)tempObject.get("image");
                tempFile.getDataInBackground(new GetDataCallback() {
                    @Override
                    public void done(byte[] bytes, com.parse.ParseException e) {
                        list.add(bytesToBitMap(bytes));
                    }
                });
            }
        }
    });
}

public static Bitmap bytesToBitMap(byte[] bytes){
    Bitmap bitmap = BitmapFactory
                            .decodeByteArray(
                                    bytes, 0,
                                    bytes.length);
    return bitmap;
}

At the end, the list still has a size of 0... meaning nothing was actually added to it. How can I access the byte[] variable and pull out of the inner class!?

The weird thing is, if I send the image view and set the bitmapimage there inside the inner class it works. But I want to be able to take the byte array out of the inner anonymous class and save it somewhere so I can work on it later.

Answer 1

If you're using com.parse.ParseFile , then use getData() to wait for the data. Don't use getDataInBackground() .

Same for ParseQuery , use find() .

Your problem is that BackEndUtils.downloadIntroImage(list) returns before the data has been retrieved, so imageView_intro.setImageBitmap(list.get(0)) will see an empty list.

Answer 2

If anyone experiencing this or any other similar problems, this specific case was caused by a background thread not completing on time and therefor not returning values as intented. That's why it worked to use getData instead of getDataInBackground.