async doInBackground for ImageDownloader()

dummy

 @Override
        protected Bitmap doInBackground(String... strings) {
            Bitmap bitmap = null;
            InputStream inputStream;
            try {
                // Download Image from URL
                inputStream = new URL(strings[0]).openStream();
                // Decode Bitmap
                bitmap = BitmapFactory.decodeStream(inputStream);
            } catch (Exception e) {
                e.printStackTrace();
            }
            return bitmap;
        }