core/src/in/srain/cube/image/ImageTask.java
public void notifyLoading(ImageLoadHandler handler, CubeImageView imageView) {
        if (handler == null || imageView == null) {
            return;
        }
        handler.onLoading(this, imageView);
    }
public void notifyLoading(ImageLoadHandler handler, CubeImageView imageView) {
        if (handler == null || imageView == null) {
            return;
        }
        handler.onLoading(this, imageView);
    }
notify loading

@param handler
@param imageView