wordBoundaryAtPt method

TextRange? wordBoundaryAtPt(Offset pt, { bool onlyIfInRect = true, })

Returns the TextRange for the text at the provided Offset.

Implementation

TextRange? wordBoundaryAtPt(Offset pt, {bool onlyIfInRect = true}) {
  assert(rp != null);

  if (rp != null && (!onlyIfInRect || rect.contains(pt))) {
    // Get the text position closest to the provided [Offset].
    final textPosition = rp!.getPositionForOffset(_toLocalPt(pt));

    // If the `pt` is on the right side of the last letter of a word,
    // `getPositionForOffset` returns the position AFTER the word, so
    // we subtract 1 from the position to counteract that.
    //
    // Note, word boundary ranges are clamped to the length of [text]
    // because they can extend into clipped hidden trailing text, which
    // [from] excludes from [text].
    final range = _clampedToTextLength(
      rp!.getWordBoundary(
        textPosition.offset == 0
            ? textPosition
            : TextPosition(offset: textPosition.offset - 1),
      ),
    );
    if (range.start >= 0 && range.end > range.start) {
      // If the `pt` is on the left side of the first letter of a word,
      // the range will be of the whitespace or punctuation before the
      // word, so check for that...
      if (textPosition.offset > 0 && _isNonWordRange(range)) {
        final next = _clampedToTextLength(rp!.getWordBoundary(textPosition));
        if (!_isNonWordRange(next)) {
          return next;
        }
        // Otherwise, `next` is still non-word, which happens when the
        // position has upstream affinity (e.g. it was clamped to the end
        // of a line). If the range is visible punctuation (e.g. a closing
        // quote at the end of a paragraph), select it; if it is invisible
        // whitespace, select the word before it.
        if (!_isWhitespaceRange(range)) {
          return range;
        }
        if (range.start > 0) {
          return _clampedToTextLength(
            rp!.getWordBoundary(TextPosition(offset: range.start - 1)),
          );
        }
      }
      return range;
    } else {
      // dmPrint('Word not found, invalid text range: $range');
    }
  }
  return null;
}