code: public boolean open(boolean anim) {
          if (!mEnabled) {
              return false;
          }
  
          if (mOpened) {
              return true;
          }
  
          if (!mShowing) {
              show();
          }
  
          if (anim) {
              animateOpen();
          } else {
              onEndOpen();
          }
          return true;
      }
docs: Open the board.
  
  @param anim pull-down animation.
  @return boolean false, if the board is disabled.