code: public void setTabText(int index, String text) {
          TextView tv = (TextView) mTabTitleViews.get(index);
  
          if (tv != null) {
              tv.setText(text);
          }
      }
docs: Set the text on the specified tab's TextView.
  
  @param index the index of the tab whose TextView you want to update
  @param text  the text to display on the specified tab's TextView