通过将特殊字符串%s放入summary属性，您可以告诉Android显示所选条目。
您的XML将是

<ListPreference
        android:title="@string/pref_calllog_sorting"
        android:key="@string/pref_calllog_sorting_descending"
        android:defaultValue="@string/pref_calllog_sorting_descending"
        android:entryValues="@array/pref_calllog_sorting_values"
        android:entries="@array/pref_calllog_sorting_options"
        android:summary="%s"
        />

需要在onPostCreate(Bundle savedInstanceState)方法中调用bindPreferenceSummaryToValue(findPreference(getString(R.string.pref_calllog_sorting_descending)));。在应用程序中添加SettingActivity时，自动创建bindPreferenceSymmaryToValue(Preference preference)方法。

@Override
protected void onPostCreate(Bundle savedInstanceState) {
    super.onPostCreate(savedInstanceState);
    setupActionBar();
    bindPreferenceSummaryToValue(findPreference(
            getString(R.string.pref_calllog_sorting_descending)));
}

private static void bindPreferenceSummaryToValue(Preference preference) {
    // Set the listener to watch for value changes.
    preference.setOnPreferenceChangeListener(sBindPreferenceSummaryToValueListener);

    // Trigger the listener immediately with the preference's
    // current value.
    sBindPreferenceSummaryToValueListener.onPreferenceChange(preference,
            PreferenceManager
                    .getDefaultSharedPreferences(preference.getContext())
                    .getString(preference.getKey(), ""));
}

只需添加app：useSimpleSummaryProvider=“true”即可

<ListPreference
            app:key="myKey"
            app:title="@string/line_type"
            app:defaultValue="line"
            app:entries="@array/type_entries"
            app:entryValues="@array/type_values"
            app:useSimpleSummaryProvider="true"/>