title: Get tooltip data of column chart in google charts
body: <p>I am using following code to plot column chart using google visualization API.</p>
  
  <pre><code>&lt;html&gt;
  &lt;head&gt;
      &lt;script type="text/javascript" src="https://www.google.com/jsapi"&gt;&lt;/script&gt;
      &lt;script type="text/javascript"&gt;
          google.load("visualization", "1", {packages: ["corechart"]});
          google.setOnLoadCallback(drawChart);
          function drawChart() {
              var data = google.visualization.arrayToDataTable([
                  ['Year', 'Expenses'],
                  ['2004', 400],
                  ['2005', 460],
                  ['2006', 1120],
                  ['2007', 540]
              ]);
  
              var options = {
                  hAxis: {title: 'Year', titleTextStyle: {color: 'red'}}
              };
  
              var chart = new google.visualization.ColumnChart(document.getElementById('chart_div'));
              chart.draw(data, options);
          }
      &lt;/script&gt;
  &lt;/head&gt;
  &lt;body&gt;
      &lt;div id="chart_div" style="width: 900px; height: 500px;"&gt;&lt;/div&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>When I click on one of bar it is displaying data of x and y axis in tooltip. I want data which is displayed in tooltip(2006 and 460) as alert. How to find it.</p>
  
  <p><img src="https://i.stack.imgur.com/Jx0Aw.png" alt="enter image description here"></p>