title: How do I change the tick color for CheckboxListTile
body: <p>I have my checkbox widget all set up and would like to change the tick color to green when selected (currently it is white). So I managed to change the color of the checkbox when it is un-selected to white by adding a theme. I want to change the selected tick color to green, however I cant seem to find the right option under theme to do so.</p>
  
  <p>Code:</p>
  
  <pre class="lang-dart prettyprint-override"><code>  Widget buildResultTile(data) {
      return Theme(
        data: ThemeData(unselectedWidgetColor: white),
        child:
          CheckboxListTile(
          activeColor: transparent,
          title: AutoSizeText(
            data,
            maxLines: 1,
            style: TextStyle(
              color: white,
            ),
          ),
          value: _serachSelectList.contains(data),
          onChanged: (bool value) {
            setState(() {
              if (value) {
                _serachSelectList.add(data);
              } else {
                _serachSelectList.remove(data);
              }
            });
          },
          secondary: const Icon(Icons.account_box, color: white),      
        )
      );
    } 
  </code></pre>
  
  <p>Un-selected:</p>
  
  <p><a href="https://i.stack.imgur.com/cxjY0.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/cxjY0.png" alt="enter image description here"></a> </p>
  
  <p>Selected (I want <strong>only</strong> the tick to be <code>Colors.green</code>): </p>
  
  <p><a href="https://i.stack.imgur.com/yCqxl.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/yCqxl.png" alt="enter image description here"></a></p>