title: How can I add a click event to show a tooltip in an NVD3 Pie Chart?
body: <p>There isn't much documentation on nvd3. In the following plunkr, the tooltip displays on a hover event. That's native to the framework. After reading other stackoverflow questions, one would use someting like the following to display the tooltip via a click versus the hover:</p>
  
  <pre><code>d3.selectAll('.nv-slice')
    .on('click', function(d) {
      console.log(d.data.label);
    }); 
  </code></pre>
  
  <p>How can I apply a click event to trigger the tooltip to display? 
  <a href="http://plnkr.co/edit/QYuol3Q10xsA3pziiWGl?p=preview" rel="nofollow">http://plnkr.co/edit/QYuol3Q10xsA3pziiWGl?p=preview</a></p>