scrollBack method

void scrollBack()

Scroll the scoreboard back.

This should only be called when the scoreboard is not already in its start scroll state (e.g., atStart is false).

Implementation

void scrollBack() {
  _disposer.addDisposable(_domService.scheduleRead(() {
    _readElement();
    var newValue = _scrollingMove;
    assert(_buttonSize > 0);
    if (atEnd) {
      if (newValue != null) {
        newValue -= _buttonSize;
      }
    }
    if (_transform.abs() - newValue! < 0) {
      newValue = _transform.abs();
    }
    if (_isVertical || !_isRtl) {
      _transform += newValue;
    } else {
      _transform -= newValue;
    }
    _updateTransform();
  }));
}