drawGrid method

Implementation

@override
void drawGrid([bool drawY = false]) {
  var labelCountY = getLabelCountY();
  var rangeY = gridMaxPxY - gridMinPxY;
  var spaceY = rangeY/(labelCountY-1);

  ctx.strokeStyle = gridLineStrokeStyle.toJS;
  ctx.lineWidth = gridLineWidth;
  for (var i = 0; i < labelCountY; i++) {
    ctx.beginPath();
    ctx.moveTo(gridMinPxX, gridMinPxY + spaceY*i);
    ctx.lineTo(gridMaxPxX, gridMinPxY + spaceY*i);
    ctx.stroke();
  }

  if (drawY) {
    var labelCountX = getLabelCountX();
    var labelMinPxX = gridMinPxX + max(getBarWidth(), maxLabelWidthX)/2;
    var labelMaxPxX = gridMaxPxX - max(getBarWidth(), maxLabelWidthX)/2;
    var rangeX  = labelMaxPxX - labelMinPxX;
    var spaceX = rangeX/(labelCountX-1);
    for (var i = 0; i < labelCountX; i++) {
      ctx.beginPath();
      ctx.moveTo(labelMinPxX + spaceX*i, gridMinPxY);
      ctx.lineTo(labelMinPxX + spaceX*i, gridMaxPxY);
      ctx.stroke();
    }
  }
}