Android更新语言的首选项活动

Question

在我的android应用程序中，我有一个首选项活动，让用户覆盖应用程序的语言。为了实现这一点，我在每个活动的onResume()中调用这个函数，然后重置内容视图:

    public static void checkOverrideSystemLanguage(Context context) {
    SharedPreferences prefs = PreferenceManager
            .getDefaultSharedPreferences(context);
    // Check if system's language setting needs to be overridden
    boolean overrideSystemLanguage = prefs.getBoolean(context
            .getString(R.string.pref_key_chkbx_override_system_language),
            false);
    if (overrideSystemLanguage) {
        // Get language selection and possible languages
        String localeString = prefs.getString(
                context.getString(R.string.pref_key_list_languages), "");
        List<String> possibleLanguages = Arrays.asList(context
                .getResources().getStringArray(
                        R.array.pref_values_list_languages));
        if (possibleLanguages.contains(localeString)) {
            // Change language setting in configuration
            Locale locale = new Locale(localeString);
            Locale.setDefault(locale);
            Configuration config = new Configuration();
            config.locale = locale;
            context.getResources().updateConfiguration(config,
                    context.getResources().getDisplayMetrics());
        }
        // Use default language
        else {
            overrideSystemLanguage = false;
        }
    }
    // Use default language
    if (!overrideSystemLanguage) {
        context.getResources().updateConfiguration(
                Resources.getSystem().getConfiguration(),
                context.getResources().getDisplayMetrics());
    }
}

在每一个活动中它都工作得很好。然而，在首选项活动中，当用户更改语言时，它不会立即得到更新，因为没有setContentView()方法。用户必须返回到先前的活动并再次启动preferences活动才能看到反映的语言更改。

我在onPreferenceChange()侦听器中尝试了以下操作:

1. 更新配置，删除和读取首选项:

   checkOverrideSystemLanguage(this);      
   // Remove all preferences and add them to update the language
   getPreferenceScreen().removeAll();
   addPreferencesFromResource(R.xml.preferences);
   

2. 更新配置并调用onCreate(null)

3. 完成并重新启动活动

   finish();
   startActivity(new Intent(this, PreferencesActivity.class));
   

谢谢你的帮助!

Answer 1

我有一个类似的问题，我以这种方式解决(如你所说:完成和重新启动活动)。它的工作原理!

    public class OptionsActivity extends PreferenceActivity implements YesNoDialogPreference.YesNoDialogListener, SharedPreferences.OnSharedPreferenceChangeListener {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //Options Setting
        final SharedPreferences prefs = getSharedPreferences(OptionsUtility.PREFERENCE_NAME, MODE_PRIVATE);
        String language = prefs.getString(OptionsUtility.PREFERENCE_LANGUAGE, OptionsUtility.DEFAULT_LANGUAGE);
        //Update locale
        OptionsUtility.updateLanguage(this, language);
        prefs.registerOnSharedPreferenceChangeListener(this);
        getPreferenceManager().setSharedPreferencesMode(MODE_PRIVATE);
        getPreferenceManager().setSharedPreferencesName(OptionsUtility.PREFERENCE_NAME);
        // Load the preferences from an XML resource
        addPreferencesFromResource(R.xml.preferences);
        Preference eraseGameButton = getPreferenceManager().findPreference(OptionsUtility.PREFERENCE_ERASE_GAME);
        if (eraseGameButton != null) {
            YesNoDialogPreference yesNo = (YesNoDialogPreference)eraseGameButton;
            yesNo.setListener(this);
        }
        Preference configureKeyboardPref = getPreferenceManager().findPreference("keyconfig");
        if (configureKeyboardPref != null) {
            //KeyboardConfigDialogPreference config = (KeyboardConfigDialogPreference)configureKeyboardPref;
            //config.setPrefs(getSharedPreferences(MemodroidCoreActivity.PREFERENCE_NAME, MODE_PRIVATE));
            //config.setContext(this);
        }
    }

    public void onDialogClosed(boolean positiveResult) {
        if (positiveResult) {
            DatabaseScoreManager dbsManager = new DatabaseScoreManager(getApplicationContext());
            dbsManager.resetHighScores();
            Toast.makeText(this, R.string.toast_highScoresReset,Toast.LENGTH_SHORT).show();
        }
    }

    @Override
    public void onSharedPreferenceChanged(SharedPreferences sharedPreferences,String key) {
        restartActivity();
    }
    @Override
    protected void onStop() {
        super.onStop();
        getPreferenceScreen().getSharedPreferences().unregisterOnSharedPreferenceChangeListener(this);
    }
    private void restartActivity() {
        Intent intent = getIntent();
        finish();
        startActivity(intent);
    }
    @Override
    public void onBackPressed() {
        finish();
    }
}