Fresco: When trying to fetchImageFromBitmapCache() for GIF image, imageReference is always null

Did you add compile 'com.facebook.fresco:animated-gif:1.0.1' to your build.gradle?

Yes I have that line.

compile ('com.facebook.fresco:animated-gif:1.0.1') {
        exclude module: 'bolts-android'
    }

I guess you have to use fetchDecodedImage instead since animated images are handled a bit differently than normal static bitmaps (not in the same bitmap cache currently).

However, if you want to allow people to save images, you should get the encoded image instead of the decoded image, i.e. fetchEncodedImage.

Thanks, it worked. I managed to save files with this code:

DataSource<CloseableReference<PooledByteBuffer>>
                dataSource = Fresco.getImagePipeline().fetchEncodedImage(ImageRequest.fromUri(imageUrl), App.getContext());

        DataSubscriber<CloseableReference<PooledByteBuffer>> dataSubscriber =
                new BaseDataSubscriber<CloseableReference<PooledByteBuffer>>() {
                    @Override
                    protected void onNewResultImpl(
                            DataSource<CloseableReference<PooledByteBuffer>> dataSource) {
                        if (!dataSource.isFinished()) {
                            return;
                        }
                        CloseableReference<PooledByteBuffer> ref = dataSource.getResult();
                        if (ref != null) {
                            try {
                                PooledByteBuffer pooledByteBuffer = ref.get();
                                PooledByteBufferInputStream sourceIs = new PooledByteBufferInputStream(pooledByteBuffer);
                                BufferedInputStream bis = new BufferedInputStream(sourceIs);
                                String newFilePath = getAppFolderPath() + UUID.randomUUID().toString().toLowerCase() + "_" + URLUtil.guessFileName(imageUrl, null, null);
                                File targetFile = new File(newFilePath);
                                createDirectories(targetFile.getPath());
                                try {
                                    BufferedOutputStream fout = new BufferedOutputStream(new FileOutputStream(newFilePath));
                                    int i;
                                    do {
                                        i = bis.read();
                                        if (i != -1)
                                            fout.write(i);
                                    } while (i != -1);
                                    bis.close();
                                    fout.close();
                                    registerMediaInDeviceGallery(new File(newFilePath));
                                    showMessage(R.string.saved_to_gallery);
                                } catch (IOException e) {
                                    targetFile.delete();
                                    e.printStackTrace();
                                    showMessage(R.string.failed_to_save_to_gallery);
                                }

                            } finally {
                                CloseableReference.closeSafely(ref);
                            }
                        }
                    }

                    @Override
                    protected void onFailureImpl(DataSource<CloseableReference<PooledByteBuffer>> dataSource) {
                        Throwable t = dataSource.getFailureCause();
                        Log.e(TAG, "onFailureImpl: ", t);
                        showMessage(R.string.failed_to_save_to_gallery);
                    }
                };

        dataSource.subscribe(dataSubscriber, Runnable::run);