@Override
    public void onUIRefreshPrepare(PtrFrameLayout frame) {

        mShouldShowLastUpdate = true;
        tryUpdateLastUpdateTime();
        mLastUpdateTimeUpdater.start();

        mProgressBar.setVisibility(INVISIBLE);

        mRotateView.setVisibility(VISIBLE);
        mTitleTextView.setVisibility(VISIBLE);
        if (frame.isPullToRefresh()) {
            mTitleTextView.setText(getResources().getString(R.string.cube_ptr_pull_down_to_refresh));
        } else {
            mTitleTextView.setText(getResources().getString(R.string.cube_ptr_pull_down));
        }
    }
Using an object to specify the last update time.

@param object
common/src/main/java/com/sxjs/common/widget/pulltorefresh/PtrClassicDefaultHeader.java