title: Chart.js tooltip not showing on line chart
body: <p>I'm at a loss as to why my chart's tooltips aren't displaying... can anybody show me what I'm doing wrong?</p>
  
  <p>The tooltips work fine if I set the chart type to "bar" but for some reason don't work with "line". I'm relatively new to chart.js and am probably making some basic newbie mistake?</p>
  
  <p>Here's my current code:</p>
  
  <pre><code>   &lt;!DOCTYPE html&gt;
  &lt;html lang="en"&gt;
  &lt;head&gt;
    &lt;meta charset="UTF-8"&gt;
    &lt;title&gt;Title&lt;/title&gt;
    &lt;script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.4.0/Chart.bundle.min.js"&gt;&lt;/script&gt;
  &lt;/head&gt;
  &lt;body onLoad="ready()"&gt;
  &lt;canvas id="myChart" width="250" height="150"&gt;&lt;/canvas&gt;
  &lt;script&gt;
    var ctx = document.getElementById("myChart");
    var myChart = new Chart(ctx, {
      type: 'line',
      data: {
        labels:[],
        datasets: [{
          label: 'Applicants',
          data: [],//start empty
          backgroundColor: [
  'rgba(10, 168, 196, 0.2)'     
          ],
          borderColor: [
  'rgba(10, 168, 196, 1)' 
          ],
        }]
      },
      options: {
          tooltips: {
              enabled: true
          },
           legend: {
              display: false
           },
  
        scales: {
         xAxes: [{
  type: 'time',
  //        time: {
   //                unit: 'day'
  
    //         }
          }],
          yAxes: [{
                  ticks: {
                      beginAtZero:true
                  }
              }]
        },
        onClick: handleClick
      }
    });
    window.onmessage = function(event){
        myChart.data.datasets[0].data = event.data.data;
     myChart.data.labels = event.data.labels;
     myChart.update();
    };
    function handleClick(e){
      var activeBars = myChart.getElementAtEvent(e);
      var value = myChart.config.data.datasets[activeBars[0]._datasetIndex].data[activeBars[0]._index];
      var label = activeBars[0]._model.label;
      window.parent.postMessage({
        "type":"click",
        "label":label,
        "value":value
      } , "*");
    }
    function ready(){
      window.parent.postMessage({"type":"ready"}, "*");
    }
  &lt;/script&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>