code: @Override
      public void postToMainThread(Runnable runnable) {
          if (mMainHandler == null) {
              synchronized (mLock) {
                  if (mMainHandler == null) {
                      mMainHandler = new Handler(Looper.getMainLooper());
                  }
              }
          }
          //noinspection ConstantConditions
          mMainHandler.post(runnable);
      }
docs: /* (non-Javadoc)
  @see com.abubusoft.kripton.android.sqlite.executors.TaskExecutor#postToMainThread(java.lang.Runnable)