对每应用语言偏好的支持刚刚添加到API 33 (Android 13，提拉米苏目前在开发者预览版)。

要改变应用程序的语言环境，只需从LocaleManager调用setApplicationLocales:

// Set app locale to pt-BR (Portuguese, Brazil)
getSystemService(LocaleManager::class.java)
    .applicationLocales = LocaleList(Locale.forLanguageTag("pt-BR"))

详见https://developer.android.com/about/versions/13/features/app-languages#api-impl

我已经写了一篇关于这个功能的文章https://proandroiddev.com/exploring-the-new-android-13-per-app-language-preferences-8d99b971b578

我终于弄清楚如何设置它工作在两个=N安卓版本。

用你自己的抽象类扩展AppCompatActivity，比如:

abstract class MLAppCompatActivity : AppCompatActivity() {
  override fun attachBaseContext(newBase: Context?) {
    super.attachBaseContext(LocaleHelper.wrap(newBase))
  }

  override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.N) {
        LocaleHelper.wrap(this)
    }
  }
}

attachBaseContext在Android >=N版本上被调用，这样activity将使用正确的上下文。在Android <N上，我们必须以另一种方式调用这个函数，在设置内容视图之前。因此，我们重写onCreate函数来设置正确的上下文。 意思是，每当你创建一个新的Activity时，你必须扩展你的抽象类。比如这个:

class TermsActivity : MLAppCompatActivity() {
  override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_terms)
  }
}

最后LocaleHelper是这样的:

import android.annotation.TargetApi;
import android.content.Context;
import android.content.ContextWrapper;
import android.content.SharedPreferences;
import android.content.res.Configuration;
import android.content.res.Resources;
import android.os.Build;
import android.util.DisplayMetrics;

import com.at_zone.constants.SharedPreferencesKeys;

import java.util.Locale;

public class LocaleHelper extends ContextWrapper {

    public LocaleHelper(Context base) {
        super(base);
    }

    public static Context wrap(Context context) {
        SharedPreferences sharedPreferences = context.getSharedPreferences(
                SharedPreferencesKeys.SHARED_PREFERENCES, Context.MODE_PRIVATE
        );
        String language = sharedPreferences.getString(SharedPreferencesKeys.CURRENT_LANGUAGE, "default");
        if (!language.equals("default")) {
            Configuration config = context.getResources().getConfiguration();
            if (!language.equals("")) {
                Locale locale = new Locale(language);
                Locale.setDefault(locale);
                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
                    setSystemLocale(config, locale);
                } else {
                    setSystemLocaleLegacy(context, config, locale);
                }
                config.setLayoutDirection(locale);
                context = context.createConfigurationContext(config);
            }
            return new LocaleHelper(context);
        }
        return context;
    }

    public static String getSystemLanguage(Context context) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
            return getSystemLocale(context).getLanguage().toLowerCase();
        } else {
            return getSystemLocaleLegacy(context).getLanguage().toLowerCase();
        }
    }

    public static Locale getSystemLocaleLegacy(Context context) {
        Configuration config = context.getResources().getConfiguration();
        return config.locale;
    }

    @TargetApi(Build.VERSION_CODES.N)
    public static Locale getSystemLocale(Context context) {
        return context.getResources().getConfiguration().getLocales().get(0);
    }

    public static void setSystemLocaleLegacy(Context context, Configuration config, Locale locale) {
        config.locale = locale;
        Resources res = context.getResources();
        DisplayMetrics dm = res.getDisplayMetrics();
        res.updateConfiguration(config, dm);
    }

    @TargetApi(Build.VERSION_CODES.N)
    public static void setSystemLocale(Configuration config, Locale locale) {
        config.setLocale(locale);
    }

}

/*change language at Run-time*/
//use method like that:
//setLocale("en");
 public void setLocale(String lang) { 
  myLocale = new Locale(lang);         
  Resources res = getResources();         
  DisplayMetrics dm = res.getDisplayMetrics();         
  Configuration conf = res.getConfiguration();         
  conf.locale = myLocale;         
  res.updateConfiguration(conf, dm);         
  Intent refresh = new Intent(this, AndroidLocalize.class);         
  startActivity(refresh); 
 }

如果你想在你的应用中保持语言变化，你必须做两件事。

首先，创建一个base Activity，让你所有的Activity都从下面扩展:

public class BaseActivity extends AppCompatActivity {

    private Locale mCurrentLocale;

    @Override
    protected void onStart() {
        super.onStart();

        mCurrentLocale = getResources().getConfiguration().locale;
    }

    @Override
    protected void onRestart() {
        super.onRestart();
        Locale locale = getLocale(this);

        if (!locale.equals(mCurrentLocale)) {

            mCurrentLocale = locale;
            recreate();
        }
    }

    public static Locale getLocale(Context context){
        SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(context);

        String lang = sharedPreferences.getString("language", "en");
        switch (lang) {
            case "English":
                lang = "en";
                break;
            case "Spanish":
                lang = "es";
                break;
        }
        return new Locale(lang);
    }
}

注意，我将新语言保存在sharedPreference中。

其次，像这样创建一个应用程序的扩展:

    public class App extends Application {

    @Override
    public void onCreate() {
        super.onCreate();
        setLocale();
    }

    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        setLocale();
    }

    private void setLocale() {

        final Resources resources = getResources();
        final Configuration configuration = resources.getConfiguration();
        final Locale locale = getLocale(this);
        if (!configuration.locale.equals(locale)) {
            configuration.setLocale(locale);
            resources.updateConfiguration(configuration, null);
        }
    }
}

注意，getLocale()与上面相同。

这是所有! 我希望这能帮助到一些人。

如果你正在使用片段，并且你想在Android中以编程方式更改应用程序语言，请使用此方法

  public void setLocale(Activity activity, String languageCode) {
    Locale locale = new Locale(languageCode);
    Locale.setDefault(locale);
    Resources resources = activity.getResources();
    Configuration config = resources.getConfiguration();
    config.setLocale(locale);
    resources.updateConfiguration(config, resources.getDisplayMetrics());
     SettingsFragment settingsFragment = new SettingsFragment();
     FragmentManager fragmentManager = requireActivity().getSupportFragmentManager();
     FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
    activity.overridePendingTransition(0,0);
     fragmentTransaction.replace(R.id.main, settingsFragment).commit();
}

这样叫它

setLocale(requireActivity(),"fr");

只需要用你的片段名改变SettingsFragment，在你调用方法的地方，这基本上是刷新布局来获得视图上的新字符串 如果你想在另一个类上设置这个方法只需像这样添加context

public void setLocale(Activity activity, String languageCode,Context context) {
    Locale locale = new Locale(languageCode);
    Locale.setDefault(locale);
    Resources resources = activity.getResources();
    Configuration config = resources.getConfiguration();
    config.setLocale(locale);
    resources.updateConfiguration(config, resources.getDisplayMetrics());
    SettingsFragment settingsFragment = new SettingsFragment();
    FragmentManager fragmentManager = ((AppCompatActivity) context).getSupportFragmentManager();
    FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
    activity.overridePendingTransition(0,0);
    fragmentTransaction.replace(R.id.main, settingsFragment).commit();
}

Mayuri的答案是正确的，但这只适用于Api 33或更高的版本。以下是逐步向后兼容的解决方案:

步骤1:在res/xml文件夹下创建locales_config.xml。

//res/xml/locales_config.xml
<?xml version="1.0" encoding="utf-8"?>
<locale-config xmlns:android="http://schemas.android.com/apk/res/android">
    <!-- Add your required languages -->
    <locale android:name="hi" />
    <locale android:name="en" />
</locale-config>

步骤2:在Application的Manifest中添加localeConfig

<manifest>
<application
    android:localeConfig="@xml/locales_config">
</application>

步骤3:在Manifest中应用此服务

<service
android:name="androidx.appcompat.app.AppLocalesMetadataHolderService"
android:enabled="false"
android:exported="false">
<meta-data
  android:name="autoStoreLocales"
  android:value="true" />
</service>

步骤4:在应用程序的模块级构建中使用resConfigs属性指定相同的语言。gradle文件:

  android {
  defaultConfig {
      ...
      resConfigs "hi","en"
  }
  }

(要求appCompat版本1.6.0或更高)

implementation 'androidx.appcompat:appcompat:1.6.0'

第5步:现在你可以使用下面的代码来更改应用程序语言(在android 9,10,12和13上测试)

  LocaleListCompat appLocale = LocaleListCompat.forLanguageTags("hi"); //Give user selected language code 
  AppCompatDelegate.setApplicationLocales(appLocale);