Async Task onPost throws exception

Issue

I am downloading image from firebase in async task and then place it in a imageview and till here, all is fine. In onPostExecute() method, I want to get the drawable from the imageview I put image in in the first step but it throws exception as it imageview contains nothing.

public class DownloadPhoto extends AsyncTask<Void, Void, Void> {
    @Override
    protected Void doInBackground(Void... params) {
        downloadImage();
        return null;
    }

    @Override
    protected void onPostExecute(Void result) {
        super.onPostExecute(result);
        Bitmap bitmap = ((BitmapDrawable) image.getDrawable()).getBitmap();
        Palette colorPalette = Palette.from(bitmap).generate();
        int darkVibrantColor = colorPalette.getDarkVibrantColor(Color.parseColor("#546369"));
        title.setTextColor(darkVibrantColor);
        details.setTextColor(darkVibrantColor);
    }

}

I do not have any problem with downloading, it downloads and puts image in imageview correctly. I though, I am better off downloading image in main treat not in async task but not sure if it is okay.

Download image function

private void downloadProfileImage() {
    downloadImage = new DownloadImage("image_" + id + ".jpg", storageReference);
    downloadImage.download(image);
}

Download Class

public class DownloadImage {
private String name;
private StorageReference storageReference;

public DownloadImage(String name, StorageReference storageReference) {
    this.name = name;
    this.storageReference = storageReference;
}

public void download(final ImageView ımageView) {
    StorageReference sRef = storageReference.child("images/" + name);
    sRef.getDownloadUrl().addOnSuccessListener(new OnSuccessListener<Uri>() {
        @Override
        public void onSuccess(Uri uri) {
            Picasso.get().load(uri).into(ımageView);
        }
    }).addOnFailureListener(new OnFailureListener() {
        @Override
        public void onFailure(@NonNull Exception e) {
            Log.i("resultDownload", e.getLocalizedMessage());
        }
    });
}
}

Solution

Try this code

Picasso mPicasso = Picasso.with(this);
            mPicasso.load(imageUrl)
                    .into(image1, new com.squareup.picasso.Callback() {


            @Override
                    public void onSuccess() {
                        Drawable drawable = image1.getDrawable();

                        // ...
                    }

                    @Override
                    public void onError() {
                        // ...
                    }
                });

Answered By - Athira