LyricLayout.compute constructor

LyricLayout.compute(LyricModel model, LyricStyle style, Size viewSize)

Implementation

factory LyricLayout.compute(
  LyricModel model,
  LyricStyle style,
  Size viewSize,
) {
  final maxWidth = viewSize.width;
  final lineMetrics = <LineMetrics>[];
  for (var line in model.lines) {
    final textPainter = TextPainter(
      textAlign: style.lineTextAlign,
      textDirection: TextDirection.ltr,
    );
    final activeTextPainter = TextPainter(
      textAlign: style.lineTextAlign,
      textDirection: TextDirection.ltr,
    );
    final translationTextPainter = TextPainter(
      textAlign: style.lineTextAlign,
      textDirection: TextDirection.ltr,
    );
    textPainter.text = TextSpan(text: line.text, style: style.textStyle);
    textPainter.layout(maxWidth: maxWidth);

    final metrics = textPainter.computeLineMetrics();
    final height = textPainter.height;
    final width = textPainter.width;

    activeTextPainter.text =
        TextSpan(text: line.text, style: style.activeStyle);
    activeTextPainter.layout(maxWidth: maxWidth);
    final activceLineMetrics = activeTextPainter.computeLineMetrics();
    final highlightWidth = activeTextPainter.width;
    final highlightHeight = activeTextPainter.height;

    double translationWidth = 0;
    double translationHeight = 0;

    if (line.translation != null) {
      translationTextPainter.text = TextSpan(
        text: line.translation,
        style: style.translationStyle,
      );
      translationTextPainter.layout(maxWidth: maxWidth);
      translationWidth = translationTextPainter.width;
      translationHeight = translationTextPainter.height;
    }
    final words = _calcWordMetrics(
        line, textPainter, activeTextPainter, translationTextPainter);
    lineMetrics.add(
      LineMetrics(
        line: line,
        height: height,
        width: width,
        activeWidth: highlightWidth,
        activeHeight: highlightHeight,
        translationWidth: translationWidth,
        translationHeight: translationHeight,
        activeMetrics: activceLineMetrics,
        metrics: metrics,
        words: words,
        textPainter: textPainter,
        activeTextPainter: activeTextPainter,
        translationTextPainter: translationTextPainter,
      ),
    );
  }
  return LyricLayout._internal(
    lineMetrics,
    style,
    viewSize,
    style.calcSelectionAnchorPosition(viewSize.height),
    style.calcActiveAnchorPosition(viewSize.height),
  );
}