demo.html

<!doctype html>
<html>
<head>
  <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
  <title>lens-viz-g-regions Demo</title>

  <script src="../webcomponentsjs/webcomponents.js"></script>
  <link rel="import" href="lens-viz-g-regions.html">

</head>
  
  <style>
    body {
      font-family: arial;
      background-color: #303B49;
      color: #FFF;
    }
  </style>
<body unresolved>

  <p>An `lens-viz-g-regions` looks like this:</p>

  <lens-viz-g-regions></lens-viz-g-regions>
    
</body>
  <script> 
    document.addEventListener('polymer-ready', function() {
        var chart = document.querySelector('lens-viz-g-regions'); 
        document.addEventListener('google-chart-render', function() {
          console.log('changing selection');
          chart.selection = [{row: 1, column: null}];
        })
        document.addEventListener('google-chart-select', function(e) {
          console.log(e);
          console.log(chart.selection);
        })


    })
  </script>
</html>