在运行每个Activity时，必须对attachBaseContext函数进行这些更改。

public Context createConfiguration(Context context, String lan) {
    Locale locale = new Locale(lan);
    Configuration configuration = new Configuration(context.getResources().getConfiguration());
    configuration.setLocale(locale);
    return context.createConfigurationContext(configuration);
}

@Override
protected void attachBaseContext(Context newBase) {
    super.attachBaseContext(createConfiguration(newBase, "en"/*LANGUAGE_SELECTED*/)));
}

同样，对于您所在的活动，在更改语言后，调用函数recrere ();

唯一完全适合我的解决方案是结合Alex Volovoy的代码和应用程序重启机制:

void restartApplication() {
    Intent i = new Intent(MainTabActivity.context, MagicAppRestart.class);
    i.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
    i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
    MainTabActivity.context.startActivity(i);
}


/** This activity shows nothing; instead, it restarts the android process */
public class MagicAppRestart extends Activity {
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        finish();
    }

    protected void onResume() {
        super.onResume();
        startActivityForResult(new Intent(this, MainTabActivity.class), 0);         
    }
}

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

这是有可能的。您可以设置区域。然而，我不建议这样做。我们在早期阶段尝试过，基本上是在对抗这个系统。

我们对改变语言有同样的要求，但决定接受UI应该与手机UI相同的事实。它是通过设置locale工作，但太bug了。根据我的经验，每次输入活动(每个活动)时都必须设置它。这里是一个代码，如果你仍然需要这个(再次强调，我不推荐)

Resources res = context.getResources();
// Change locale settings in the app.
DisplayMetrics dm = res.getDisplayMetrics();
android.content.res.Configuration conf = res.getConfiguration();
conf.setLocale(new Locale(language_code.toLowerCase())); // API 17+ only.
// Use conf.locale = new Locale(...) if targeting lower versions
res.updateConfiguration(conf, dm);

如果您有特定于语言的内容-您可以根据设置更改它。

2020年3月26日更新

    public static 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());
    }

注意:语言代码不能有“-”，必须是2个小写字母

下面是一些适合我的代码:

public class  MainActivity extends AppCompatActivity {
    public static String storeLang;

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        SharedPreferences shp = PreferenceManager.getDefaultSharedPreferences(this);
        storeLang = shp.getString(getString(R.string.key_lang), "");

        // Create a new Locale object
        Locale locale = new Locale(storeLang);

        // Create a new configuration object
        Configuration config = new Configuration();
        // Set the locale of the new configuration
        config.locale = locale;
        // Update the configuration of the Accplication context
        getResources().updateConfiguration(
                config,
                getResources().getDisplayMetrics()
        );

        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
}

来源:这里

这段代码真的可以工作:

fa = 波斯语，en = 英语

注意:语言代码不能有“-”，必须是2个小写字母

在languageToLoad变量中输入您的语言代码:

import android.app.Activity;
import android.content.res.Configuration;
import android.os.Bundle;

public class Main extends Activity {
  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    String languageToLoad  = "fa"; // your language
    Locale locale = new Locale(languageToLoad); 
    Locale.setDefault(locale);
    Configuration config = new Configuration();
    config.locale = locale;
    getBaseContext().getResources().updateConfiguration(config, 
      getBaseContext().getResources().getDisplayMetrics());
    this.setContentView(R.layout.main);
  }
}

2021年6月更新(Kotlin):

class Main : Activity() {
    // Called when the activity is first created.
    public override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        
        val config = resources.configuration
        val lang = "fa" // your language code
        val locale = Locale(lang)
        Locale.setDefault(locale)
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1)
            config.setLocale(locale)
        else
            config.locale = locale

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N)
            createConfigurationContext(config)
        resources.updateConfiguration(config, resources.displayMetrics)

        this.setContentView(R.layout.main)
    }
}