title: How to apply theme to <PreferenceScreen> elements of a <PreferenceCategory>
body: <p>I have an activity that extends PreferenceActivity.</p>
  
  <p>My theme : android:theme="@android:style/Theme.Light.NoTitleBar.Fullscreen" is applied to the application level in the Manifest file.</p>
  
  <p>Everything is getting the desired theme except the "PreferenceScreen" elements of "PreferenceCategory". They are still having the default black background. In simple words, the main Preference Category screen which has the parent Preference Screens are getting the theme but if I click on any of the PreferenceScreens to go to their element preferences(EditText  etc etc), they are not getting the theme...</p>
  
  <p>Any Idea why this might be happening?</p>
  
  <p>The structure or preferences.xml is something like this :</p>
  
  <pre><code>&lt;PreferenceCategory&gt;
  
      &lt;PreferenceScreen&gt;
          &lt;EditTextPreference&gt;
          ...
          &lt;/EditTextPreference&gt;
          &lt;EditTextPreference&gt;
          ...
          &lt;/EditTextPreference&gt;
          ...
      &lt;/PreferenceScreen&gt;
  
      &lt;PreferenceScreen&gt;
      ...
      &lt;/PreferenceScreen&gt;
  
  &lt;/PreferenceCategory&gt;
  </code></pre>