title: Flutter Switch - onChanged Not Changing
body: <p>When using the following <code>Switch</code> widget, the <code>isOn</code> value always returns <code>true</code> and never changes.</p>
  
  <p>The <code>Switch</code> only moves position on a swipe too, a tap won't move it. How to resolve?</p>
  
  <pre><code>bool isInstructionView = false;
  
  Switch(
      value: isInstructionView,
      onChanged: (bool isOn) {
        setState(() {
          isInstructionView = isOn;
          print(isInstructionView);
        });
      },
      activeColor: Colors.blue,
      inactiveTrackColor: Colors.grey,
      inactiveThumbColor: Colors.grey,
  )
  </code></pre>
  
  <p><strong>Update</strong>: For extra clarity, <code>onChanged</code> always returns <code>isOn</code> as <code>true</code>. Why would this be?</p>