drawVerticalText method

@override void drawVerticalText({ required Canvas canvas, required TextStyle style, required double maxValue, required double minValue, required int fixedLength, required Rect chartRect, })

Implementation

@override
void drawVerticalText({
  required Canvas canvas,
  required TextStyle style,
  required double maxValue,
  required double minValue,
  required int fixedLength,
  required Rect chartRect,
}) {
  List<int> rangeValue = [80, 20];
  final spaceRange = maxValue - minValue;

  for (int i = 0; i < rangeValue.length; ++i) {
    final value = rangeValue[i];
    if (value < minValue || value > maxValue) continue;
    TextPainter tp = TextPainter(
      text: TextSpan(
        text: value.toString(),
        style: style,
      ),
      textDirection: TextDirection.ltr,
    );
    tp.layout();
    final ratio = (value - minValue) / spaceRange;
    final x = chartRect.width - tp.width;
    final y = chartRect.bottom - ratio * chartRect.height - tp.height / 2;
    tp.paint(
      canvas,
      Offset(x, y.clamp(chartRect.top, chartRect.bottom - tp.height)),
    );
  }
}