Generates a CSS selector for the connectors of a dumbbell series.
A dumbbell draws three elements per row: the two dots, which
AreaRangeSeries#drawPoints renders as ordinary markers carrying the point
class (plus highcharts-lollipop-low / -high), and the segment between
them, a <path class="highcharts-lollipop-stem"> that drawConnector adds
for every row. A .highcharts-point selector would therefore return two
elements per row, which is one too many: MAIDR's DumbbellTrace wants one
element per row and highlights the same one from both ends, since the chart
draws one connector per row and not one element per dot.
The connector is also the more dependable of the two. Highcharts drops the
markers when the points get dense enough to overlap
(marker.enabledThreshold), while drawConnector runs unconditionally.
Generates a CSS selector for the connectors of a
dumbbellseries.A dumbbell draws three elements per row: the two dots, which
AreaRangeSeries#drawPointsrenders as ordinary markers carrying the point class (plushighcharts-lollipop-low/-high), and the segment between them, a<path class="highcharts-lollipop-stem">thatdrawConnectoradds for every row. A.highcharts-pointselector would therefore return two elements per row, which is one too many: MAIDR'sDumbbellTracewants one element per row and highlights the same one from both ends, since the chart draws one connector per row and not one element per dot.The connector is also the more dependable of the two. Highcharts drops the markers when the points get dense enough to overlap (
marker.enabledThreshold), whiledrawConnectorruns unconditionally.