Highcharts redraw and sort data on draggable line graph

Question

I have a line chart in Highcharts and want to redraw or the line when dragging a point past another point.

I want to redraw and sort the chart while dragging so the line updates and don't cross eachother. We can update the chart with chart.series[0].setData() or chart.series[0].update(); but i keep getting sorting errors or errors with the draggable point being null (dragPoint or hoverPoint) when updating the chart

Here is an example where I detect when a point is being dragged past another by changing the getNewPos(e) function in the draggable module http://jsfiddle.net/u4xpmf2j/1/

 */
function getNewPos(e) {
  toClose = false;
  var originalEvent = e.originalEvent || e,
    pageX = originalEvent.changedTouches ? originalEvent.changedTouches[0].pageX : e.pageX,
    pageY = originalEvent.changedTouches ? originalEvent.changedTouches[0].pageY : e.pageY,
    series = dragPoint.series,
    draggableX = series.options.draggableX && dragPoint.draggableX !== false,
    draggableY = series.options.draggableY && dragPoint.draggableY !== false,
    dragSensitivity = pick(series.options.dragSensitiviy, 1),
    dragMaxToPoint = pick(series.options.dragMaxToPoint, 0.3),
    deltaX = draggableX ? dragX - pageX : 0,
    deltaY = draggableY ? dragY - pageY : 0,
    newPlotX = dragPlotX - deltaX,
    newPlotY = dragPlotY - deltaY,
    newX = dragX === undefined ? dragPoint.x : series.xAxis.toValue(newPlotX, true),
    newY = dragY === undefined ? dragPoint.y : series.yAxis.toValue(newPlotY, true),
    ret;
  newX = filterRange(newX, series, 'X');
  newY = filterRange(newY, series, 'Y');
  if (dragPoint.index > 0 && (newX - dragPoint.series.data[dragPoint.index - 1].x) < dragMaxToPoint || dragPoint.index < dragPoint.series.data.length - 1 && (newX - dragPoint.series.data[dragPoint.index + 1].x) > -dragMaxToPoint) {
    toClose = true; // DETECT POINT BEING DRAGGED PAST ANOTHER
  }
  if (Math.sqrt(Math.pow(deltaX, 2) + Math.pow(deltaY, 2)) > dragSensitivity) {
    return {
      x: draggableX ? newX : dragPoint.x,
      y: draggableY ? newY : dragPoint.y
    };
  } else {
    return null;
  }
}

Any ideas?

Wojciech Chmiel Wojciech Chmiel · Accepted Answer · 2018-11-28T15:52:37

How about sorting data after drop event and then use series.setData to update the chart:

  plotOptions: {
    series: {
      point: {
        events: {
          drop: function() {
            var series = this.series,
                xData = series.xData.slice(),
                yData = series.yData.slice(),
                newData = [];

            xData.forEach(function(data, i) {
                newData.push([
                data,
                yData[i]
              ]);
            });

            newData.sort(function(a, b) {
                return a[0] - b[0];
            });

            series.setData(newData, false, false);     
            series.chart.redraw();
          }
        }
      },
      stickyTracking: false
    },
  }

Demo: http://jsfiddle.net/BlackLabel/6kyt3roL/

Highcharts redraw and sort data on draggable line graph

1 Answers