code: protected void processUrl(final String url) {
          try {
              final Result result = mProcessor.processUrl(url);
              post(new Runnable() {
                  @Override
                  public void run() {
                      if (isAttachedToWindow()) {
                          postProcessUrl(url, result);
                      }
                  }
              });
          } catch (Throwable ex) {
              if (LOGGING) {
                  Log.wtf(LOG_TAG, ex);
              }
          }
      }
docs: Background thread