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

对于Android 7.0牛轧糖(或更低)，请遵循这篇文章:

在Android中以编程方式改变语言

旧的答案 这包括RTL/LTR支持:

public static void changeLocale(Context context, Locale locale) {
    Configuration conf = context.getResources().getConfiguration();
    conf.locale = locale;
    Locale.setDefault(locale);

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1) {
       conf.setLayoutDirection(conf.locale);
    }

    context.getResources().updateConfiguration(conf, context.getResources().getDisplayMetrics());
}

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);         
    }
}

首先为不同的语言创建多个string.xml;然后在onCreate()方法中使用这段代码:

super.onCreate(savedInstanceState);
String languageToLoad  = "fr"; // change your language here
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);

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。

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 ();