Android: BitmapFactory.decodeStream OutOfMemoryException - is SoftReference the solution?

Question

I'm getting an OutOfMemoryException:

E/AndroidRuntime( 3013): java.lang.OutOfMemoryError: bitmap size exceeds VM budget
E/AndroidRuntime( 3013):        at android.graphics.BitmapFactory.nativeDecodeStream(Native Method)
E/AndroidRuntime( 3013):        at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:375)
E/AndroidRuntime( 3013):        at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:394)

In the following function:

static Bitmap downloadBitmap(String url)
    {
        final HttpClient client = new DefaultHttpClient();
        final HttpGet getRequest = new HttpGet(url);

        try 
        {
            HttpResponse response = client.execute(getRequest);
            final int statusCode = response.getStatusLine().getStatusCode();

            // Check HTTP Status code
            if (statusCode != HttpStatus.SC_OK)
            { 
                debugPrint("ImageDownloader StatusCode Error " + statusCode + " while retrieving bitmap from " + url);
                return null;
            }
            else;


            final HttpEntity entity = response.getEntity();

            if (entity != null)
            {
                InputStream inputStream = null;
                try
                {
                    inputStream = entity.getContent(); 
                    if( inputStream == null)
                    {
                        debugPrint("ImageDownloader::downloadBitmap() - INPUTSTREAM = NULL!!!!!!");
                    }
                    else;



                    // THIS LINE IS GIVING THE ERROR
                    final Bitmap bitmap = BitmapFactory.decodeStream( new FlushedInputStream(inputStream));

                    if( bitmap == null)
                    {
                        debugPrint("LocrPhoto::downloadBitmap() - about to return BITMAP =NULL!!!!!!");
                    }
                    else;

                    return bitmap;
                }
                catch (Exception e)
                {
                    // Could provide a more explicit error message for IOException or IllegalStateException
                    getRequest.abort();
                    debugPrint("LocrPhoto::downloadBitmap() Error while decoding bitmap from " + url + "\n"+ e.toString());
                }
                finally
                {
                    if (inputStream != null)
                    {
                        inputStream.close();  
                    }
                    entity.consumeContent();
                }
            }
            else
            {
                debugPrint("LocrPhoto::downloadBitmap("+url+") - entity = NULL!!!!!");
            }
        }
        catch (Exception e)
        {
            // Could provide a more explicit error message for IOException or IllegalStateException
            //getRequest.abort();
            debugPrint("LocrPhoto::downloadBitmap() Error while retrieving bitmap from " + url + "\n"+ e.toString());
        }
        finally
        {
            if (client != null)
            {
                // CLOSE CONNECTION
            }
        }
        debugPrint("LocrPhoto::downloadBitmap("+url+") - returning NULL at end of function");
        return null;
    }

FlushedInputStream (though I got the error before adding this code):

// A Class to hopefully avoid the BitmapFactory.decodeStream() returning null bug
    //      http://code.google.com/p/android/issues/detail?id=6066
    static class FlushedInputStream extends FilterInputStream {
        public FlushedInputStream(InputStream inputStream) {
            super(inputStream);
        }

        @Override
        public long skip(long n) throws IOException {
            long totalBytesSkipped = 0L;
            while (totalBytesSkipped < n) {
                long bytesSkipped = in.skip(n - totalBytesSkipped);
                if (bytesSkipped == 0L) {
                      int byt = read();
                      if (byt < 0) {
                          break;  // we reached EOF
                      } else {
                          bytesSkipped = 1; // we read one byte
                      }
               }
                totalBytesSkipped += bytesSkipped;
            }
            return totalBytesSkipped;
        }
    }

Basically, I have an activity that downloads images, places them in a framelayout and fades frames in and out to give a slideshow. The framelayout has two imageview children.

I've seen people speak of SoftReference being used to prevent OOMExceptions, but I can't understand how this would be applied to my code to (hopefully) prevent this error.

Could anyone explain how this might be achieved?

Answer 1

I was dealing with the same problem as you and I found that the problem is the memory consumption of the BitmapFactory.decodeStream (as the log says). What you have to do is scale your bitmap just before the call of BitmapFactory.decodeStream, you can find a very nice article that will resolve your problem!

http://developer.android.com/training/displaying-bitmaps/load-bitmap.html

Hope it helps!