title: Chart.js / HTML Canvas - move line
body: <p>I need to move vertical line on HTML canvas using Chart.js.</p>
  
  <p>I am using this:</p>
  
  <pre><code>this.chart.ctx.beginPath();
  this.chart.ctx.moveTo(point.x, scale.startPoint + 24);
  this.chart.ctx.strokeStyle = '#ff0000';
  this.chart.ctx.lineTo(point.x, scale.endPoint);
  this.chart.ctx.stroke();`
  </code></pre>
  
  <p><a href="http://jsfiddle.net/dbyze2ga/377/" rel="nofollow">http://jsfiddle.net/dbyze2ga/377/</a> but what I need is to move the line to another index when button on the web page is clicked. I read about html canvas and found that it is "impossible" to remove line but then I found that: <a href="https://jsfiddle.net/ombaww9t/2/" rel="nofollow">https://jsfiddle.net/ombaww9t/2/</a> and the line is moving.</p>
  
  <p>So what I need is probably combination of those two examples.</p>
  
  <p>Thanks for response.</p>