nvd3.js chart ajax data redraw - missing hovereffect + former yAxis scale

Question

I am using nvd3 to draw a simple line chart with data receiving via an ajax request. It is working perfectly with the first drawing request but not on redrawing. The chart redraws by calling the same drawing function but with different data + differen max/min values.

When redrawing the chart with new data the "hover circle" does not appear, whereas the tooltip does. Furthermore when clicking on the legend of the chart and force a redraw by that the hover appears again, but the values of the yAxis are changed to these of the first drawn chart.

So far I assume that when redrawing the chart still holds the old max/min values - but only concerning the "hover" effect. The general chart looks fine so far also on redraw - the problem just faces the hover and that's it.

Sounds pretty confusing, but hopefully you will get the point.

Some code:

 d3.json(queryurl, function(data2){
  nv.addGraph(function(jsonData) {
    if(chart){
       chart.remove();
    }
    chart = nv.models.lineChart()
                .x(function(d) { return d[0] })
                .y(function(d) { return d[1] })
                .color(d3.scale.category10().range());

    chart.xAxis
        .tickFormat(function(d) {
            return d3.time.format('%x')(new Date(d)) 
        });

    chart.yAxis
        .scale()
        .tickFormat(d3.format(''));

    chart.lines.yDomain([maxmin.max,maxmin.min]);

    d3.select('#chart1 #chartsvg')
      .datum(data2)
      .transition().duration(600)
      .call(chart);

    nv.utils.windowResize(chart.update);

});

});
  return chart;}

Mendes

Answer 1

Try using .empty() on the svg element before redrawing.

Obligate

Answer 2

I've only just started with NVD3 and D3 myself, however am doing a similar thing. What worked for me is to separate the data update function with the chart creation function. Do note the caveat below though...

I have the following to create the graph:

initGraph = function(url) {
  d3.json(url, function(data) {
    nv.addGraph(function() {
      chart = nv.models.multiBarChart();

      d3.select('#chart svg').datum(data).transition().duration(500).call(chart);
      nv.utils.windowResize(chart.update);

      return chart;
    });
  });
};

And the following function to update it:

redrawGraph = function(url) {
  d3.json(url, function(data) {

    d3.select('#chart svg').datum(data).transition().duration(500).call(chart);
    nv.utils.windowResize(chart.update);
  });
};

I don't know if this is the recommended solution as I'm still at the "hack until it works" stage. With this, all the functions of the chart work after invocation of redrawGraph() (including axes redraw and tooltips).

Caveat: this seems to occasionally result in miscalculated ticks on recalculation:

Chil

See my workaround for the tick issue - essentially, redrawing the chart. – Chil