title: Why does the nested PreferenceScreen not open when using AndroidX?
body: <p>I am using AndroidX's Preference library to manage my app's settings. My <code>SettingsFragment</code> derives from <code>PreferenceFragmentCompat</code> and loads the following layout:</p>
  
  <pre><code>&lt;androidx.preference.PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"&gt;
  
      &lt;androidx.preference.PreferenceScreen
          android:key="screen_backup_key"
          android:title="@string/local_database"&gt;
  
          &lt;androidx.preference.Preference
              android:key="button_save_key"
              android:title="@string/export" /&gt;
  
          &lt;androidx.preference.Preference
              android:key="button_load_key"
              android:title="@string/_import" /&gt;
  
      &lt;/androidx.preference.PreferenceScreen&gt;
  
      &lt;androidx.preference.Preference
              android:key="screen_about"
              android:title="@string/about" /&gt;
  
  &lt;/androidx.preference.PreferenceScreen&gt;
  </code></pre>
  
  <p>The layout is displayed correctly, but when I click on the nested <code>PreferenceScreen</code> entry nothing happens. It worked before with the <code>PreferenceScreen</code> from the <em>Support Library</em>, which is now deprecated.</p>
  
  <p>I would expect to see the contents to this nested <code>PreferenceScreen</code>. What am I doing wrong?</p>