selectWordEdge method

void selectWordEdge ({@required SelectionChangedCause cause })

Move the selection to the beginning or end of a word.

Implementation 

void selectWordEdge({@required SelectionChangedCause cause}) {
  assert(cause != null);
  _layoutText(constraints.maxWidth);
  assert(_lastTapDownPosition != null);
  if (onSelectionChanged != null) {
    final TextPosition position = _textPainter.getPositionForOffset(globalToLocal(_lastTapDownPosition));
    final TextRange word = _textPainter.getWordBoundary(position);
    if (position.offset - word.start <= 1) {
      onSelectionChanged(
        TextSelection.collapsed(offset: word.start, affinity: TextAffinity.downstream),
        this,
        cause,
      );
    } else {
      onSelectionChanged(
        TextSelection.collapsed(offset: word.end, affinity: TextAffinity.upstream),
        this,
        cause,
      );
    }
  }
}