Automatically change drawer language when app resume from backstack

Question

I have implemented two language in my app \"English\" and \"French\" and both of them are working fine individually. When I am trying to check the language change with devic

Answer 1

You have two different options.

1. setting including "locale" to android:configChanges in xml. It is recommended the way of changing the language as doc says,

android:configChanges Lists configuration changes that the activity will handle itself. When a configuration change occurs at runtime, the activity is shut down and restarted by default, but declaring a configuration with this attribute will prevent the activity from being restarted. Instead, the activity remains running and its onConfigurationChanged() method is called.

Note: Using this attribute should be avoided and used only as a last-resort. Please read Handling Runtime Changes for more information about how to properly handle a restart due to a configuration change.

Any or all of the following strings are valid values for this attribute. Multiple values are separated by '|' — for example, "locale|navigation|orientation".

2. Another way is through the broadcast receiver. ACTION_LOCALE_CHANGED. You can register a BroadcastReceiver in your manifest to handle it.

Answer 2

Check this,

String language = preferences.getString("language", null);

and this is my onclick listener of button

 llChangeLanguage.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {


            if (language == null) {
                LocaleHelper.setLocale(BaseActivity.this, "de");
                Intent intent = new Intent(BaseActivity.this, HomeActivity.class);
                storeLanguageInPref("en");
                startActivity(intent);
                finish();
            } else if ("kn".contentEquals(language)) {
                LocaleHelper.setLocale(BaseActivity.this, "de");
                Intent intent = new Intent(BaseActivity.this, HomeActivity.class);
                startActivity(intent);
                storeLanguageInPref("en");
                finish();
            } else {
                LocaleHelper.setLocale(BaseActivity.this, "kn");
                Intent intent = new Intent(BaseActivity.this, HomeActivity.class);
                storeLanguageInPref("kn");
                startActivity(intent);

                finish();
            }

        }
    });

and here i am storing the selected language to preference

 private void storeLanguageInPref(String language) {
    SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(BaseActivity.this);
    SharedPreferences.Editor editor = preferences.edit();

    editor.putString("language", language);
    editor.apply();
}

LocaleHelper class

public class LocaleHelper {

public static Context onAttach(Context context) {
    String locale = getPersistedLocale(context);
    return setLocale(context, locale);
}

public static String getPersistedLocale(Context context) {
    SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(context);
    return preferences.getString(SettingsFragment.KEY_PREF_LANGUAGE, "");
}

/**
 * Set the app's locale to the one specified by the given String.
 *
 * @param context
 * @param localeSpec a locale specification as used for Android resources (NOTE: does not
 *                   support country and variant codes so far); the special string "system" sets
 *                   the locale to the locale specified in system settings
 * @return
 */
public static Context setLocale(Context context, String localeSpec) {
    Locale locale;
    if (localeSpec.equals("system")) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
            locale = Resources.getSystem().getConfiguration().getLocales().get(0);
        } else {
            //noinspection deprecation
            locale = Resources.getSystem().getConfiguration().locale;
        }
    } else {
        locale = new Locale(localeSpec);
    }
    Locale.setDefault(locale);
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
        return updateResources(context, locale);
    } else {
        return updateResourcesLegacy(context, locale);
    }
}

@TargetApi(Build.VERSION_CODES.N)
private static Context updateResources(Context context, Locale locale) {
    Configuration configuration = context.getResources().getConfiguration();
    configuration.setLocale(locale);
    configuration.setLayoutDirection(locale);

    return context.createConfigurationContext(configuration);
}

@SuppressWarnings("deprecation")
private static Context updateResourcesLegacy(Context context, Locale locale) {
    Resources resources = context.getResources();

    Configuration configuration = resources.getConfiguration();
    configuration.locale = locale;
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1) {
        configuration.setLayoutDirection(locale);
    }

    resources.updateConfiguration(configuration, resources.getDisplayMetrics());

    return context;
}
}