Bitmap is returning null when using glide

Question

I have been trying to figure out why bitmap is giving me a size value within the SimpleTarget but is null soon as am outside the SimpleTarget.

private Bitmap getImage(String path){

    final Bitmap[] bitmaps = new Bitmap[1];

    Glide.with(getApplicationContext())
            .load(path)
            .asBitmap()
            .into(new SimpleTarget<Bitmap>() {
                @Override
                public void onResourceReady(Bitmap resource, GlideAnimation<? super Bitmap> glideAnimation) {
                    bitmaps[0] = resource;
                    Log.v(TAG, "bitmap: " + bitmaps[0].getByteCount());// Returns a value as expected.
                }
            });
        Log.v(TAG, "bitmap2: " + bitmaps[0].getByteCount());// throws a null object reference.
        return bitmaps[0];
    }

Edit: AsyncTask approach.

private Bitmap getImage(String path){

    final Bitmap[] bitmaps = new Bitmap[1];

    new AsyncTask<Void, Void, Void>() {
        Bitmap tmp;

        @Override
        protected Void doInBackground(Void... params) {
            try {
                tmp = Glide.with(getApplicationContext())
                        .load("http://i.annihil.us/u/prod/marvel/i/mg/b/40/image_not_available.jpg")
                        .asBitmap()
                        .into(-1,-1)
                        .get();
            } catch (final ExecutionException | InterruptedException e) {
                Log.e(TAG, e.getMessage());
            }
            return null;
        }
        @Override
        protected void onPostExecute(Void dummy) {
            if (null != tmp) {
                // The full bitmap should be available here
                bitmaps[0] = tmp;
                Log.v(TAG, "bitmap: " + bitmaps[0].getHeight());
                Log.d(TAG, "Image loaded");
            };
        }
    }.execute();

        Log.v(TAG, "bitmap2: " + bitmaps[0].getHeight());// throws a null object reference.
        return bitmaps[0];
    }

Edit: Added log in relation to the issue.

08-04 19:35:03.687 5183-5183/com.example.comics V/com.example.comics.MainActivity: java.lang.NullPointerException: Attempt to invoke virtual method 'int android.graphics.Bitmap.getHeight()' on a null object reference
08-04 19:35:03.709 5183-5183/com.example.comics V/com.example.comics.backend.services.BackgroundService: bitmap: 537

Edit: If bitmap is not defined as final it will shout being accessed from inner class. Declare as final.

Answer 1

I have finally got it to function. 1st the bitmap had to be declared in the global workspace. (Just as an object). 2nd the Log.v had to be in an if statement, since the database is being downloaded using a Restful client service. Its not always getting the intended data.

My solution:

Edit: Bitmap bitmap = null;

private Bitmap getImage(final String path){

    new AsyncTask<Void, Void, Void>() {

        @Override
        protected Void doInBackground(Void... params) {
            try {
                bitmap = Glide.with(getApplicationContext())
                        .load(path)
                        .asBitmap()
                        .into(-1,-1)
                        .get();
            } catch (final ExecutionException | InterruptedException e) {
                Log.e(TAG, e.getMessage());
            }
            return null;
        }
        @Override
        protected void onPostExecute(Void dummy) {
        }
    }.execute();

    if(bitmap != null) {
        Log.v(TAG, "bitmap2: " + bitmap.getHeight());
    }
        return bitmap;
    }

However there is an error performing after the first 30 images. Am guessing its due to the method being called from a for loop, and resulting in the nasty list of errors.

08-04 20:20:21.191 12350-12457/com.example.comics E/com.example.comics.backend.services.BackgroundService: java.io.IOException: Request failed 404: Not Found
08-04 20:20:21.658 12350-12457/com.example.comics E/com.example.comics.backend.services.BackgroundService: java.io.IOException: Request failed 404: Not Found

Answer 2

You are creating a reference to a parameter and using it outside its function, bitmap[0] will be null when you leave the function.

You have to either create a copy of the bitmap using the following code:
bitmaps[0] = resource.copy(resource.getConfig(), true);

You should use this inside onResourceReady() body.

Or using Glide:

bitmaps[0] = Glide.with(getApplicationContext())
        .load(path)
        .asBitmap()
        .into ....
        .get();`

You need to wrap this inside a function in an asynctask and execute it. See this answer which explains loading in the background and setting the bitmap to an imageview inside the overrriden onPostExecute().