title: Add mor info to flutter tabs
body: <p>i would like to create dynamic tabs depending on categories from a HTTP service. creating the categories is not a problem as i could just use <code>List&lt;Widget&gt;.generate</code> however my problem is that depending on which tab is clicked i would like to retrieve the key of the clicked tab and make a HTTP call and thus populate the corresponding tab content, is there a way that i could associate more data with my tabs e.g include the key that i would use for a HTTP call? e.g</p>
  
  <pre><code> List&lt;Widget&gt; _buildTabs() {
        return &lt;Widget&gt;[
          Tab(//insert key as a property),
  
        ];
      }
  </code></pre>