title: Android: toggle text color of ToggleButton
body: <p>To create a custom ToggleButton, I've defined a new style in <code>/res/values/styles.xml</code>:</p>
  
  <pre><code>&lt;style name="myToggleButton"&gt;
      &lt;item name="android:layout_width"&gt;wrap_content&lt;/item&gt;
      &lt;item name="android:layout_height"&gt;wrap_content&lt;/item&gt;
      &lt;item name="android:textColor"&gt;#000000&lt;/item&gt;
      &lt;item name="android:background"&gt;@drawable/my_toggle_button&lt;/item&gt;
  &lt;/style&gt;
  </code></pre>
  
  <p>and I then use a selector to specify how the button's states look in <code>/res/drawable/my_toggle_button.xml</code>:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;selector xmlns:android="http://schemas.android.com/apk/res/android"&gt;
      &lt;item android:state_checked="true"&gt;
          &lt;shape&gt;
              [...]
          &lt;/shape&gt;
      &lt;/item&gt;
      &lt;item android:state_checked="false"
          &lt;shape&gt;
              [...]
          &lt;/shape&gt;
      &lt;/item&gt;
  &lt;/selector&gt;
  </code></pre>
  
  <p>How can I modify this setup to toggle the text color of the button when the state changes?</p>