title: ChartJs mouse hover bug (showing previous charts)
body: <p>I think my issue is a known one, everytime I make a new chart and hover my mouse over some points in the canvas, the old charts flash in and out all the time. <a href="https://github.com/jtblin/angular-chart.js/issues/187" rel="noreferrer">Here's one of the threads</a> I followed to try and fix it, but nothing seems to work. I tried re-appending the canvas, using destroy, clear, if statements which <em>should</em> clear it, but nothing.</p>
  
  <p>Here's my code:</p>
  
  <pre><code>var ctx = document.getElementById('myChart').getContext('2d');
  var myChart = new Chart(ctx, {
      type: 'line',
      data: {
          labels: chartjsDate,
          datasets: [{
              label: 'temp',
              data: chartjsTemp,
              backgroundColor: "rgba(240,240,240,0.5)"
          }]
      }
  });
  </code></pre>
  
  <p>I tried adding <code>myChart.destroy();</code> before and after that code, even <code>if(myChart!=null){myChart.destroy();}</code>, but still nothing. Any help on how to fix it would be appreciated. All other threads I found are quite old and their solutions don't work.</p>
  
  <p>Edit: Some stuff I tried, to no avail:</p>
  
  <pre><code>var myChart;
  if (myChart != undefined || myChart !=null) {
      myChart.destroy();
  }
  </code></pre>