highcharts - DateFormat in Tooltip for Scatter Plot does not change -

i integrating flask app highcharts , highcharts graph blend of 2 lines (one spline , other scatterplot). line shows correct date format in tooltip whereas scatter plot not.

i did see link can done writing javascript code:

tooltip: {     crosshairs: true,     formatter: function () {         return '<b>' + highcharts.dateformat('%e. %b %y, %h:00', this.x) + '</b> ' + this.series.name + ': ' + this.y + ' m/s';     } } 

i want without writing javascript code.

my main python code this:

series = [     {         "type":"scatter",         "name": 'data points',         "data":modified_result,         "tooltip":{"xdateformat":'%y-%m-%d'}     },     {         "type":"spline",         "name": 'trend line',         "data":line_result,         "tooltip":{"xdateformat":'%y-%m-%d'}     } ] 

and render template saying:

return flask.render_template('index.html',            result = result,            predicted_prices = predicted_prices,            chartid=chartid,            chart=chart,            series=series,            title=title,            xaxis=xaxis,            yaxis=yaxis) 

and in index.html, have:

<script>   var chart_id = {{ chartid|safe }}   var series = {{ series|safe }}   var title = {{ title|safe }}   var xaxis = {{ xaxis|safe }}   var yaxis = {{ yaxis|safe }}   var chart = {{ chart|safe }} 

which calls javascript:

$(document).ready(function() {   $(chart_id).highcharts({     chart: chart,     title: title,     xaxis: xaxis,     yaxis: yaxis,     series: series   }); }); 

the 'scatter' type has little bit different setup tooltip. take @ answer. can in series setup code xdateformat.

{     "type":"scatter",     "name": 'data points',     "data":modified_result,     "tooltip":{        "xdateformat":'%y-%m-%d',        "headerformat": '{point.key}<br />',        "pointformat": '<span style="color:{point.color}">\u25cf</span> {series.name}: <b>{point.y}</b><br/>'     } } 

you can play around inside of here set more finely how want it. sample fiddle.