title: How to fill color inside of checkbox in flutter?
body: <p>Here is what I am using for checkbox in flutter.
  But I can set only border color for unchecked state, not method found for fill color inside of the checkbox.
  Please help me with this.</p>
  <pre><code>Theme(
      data: ThemeData(unselectedWidgetColor: Colors.white),
      child: Checkbox(
          checkColor: Colors.blue,
          activeColor: Colors.white,
          value: rememberMe,
          onChanged: (value) {
              setState(() {
                  rememberMe = value;
              });
          },
      ),
  )
  </code></pre>