Changing Locale within the app itself

Hubert picture Hubert · Feb 15, 2010 · Viewed 153.7k times · Source

My users can change the Locale within the app (they may want to keep their phone settings in English but read the content of my app in French, Dutch or any other language ...)

Why is this working perfectly fine in 1.5/1.6 but NOT in 2.0 anymore ???

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch(item.getItemId()) {
    case 201:
        Locale locale2 = new Locale("fr"); 
        Locale.setDefault(locale2);
        Configuration config2 = new Configuration();
        config2.locale = locale2;
        getBaseContext().getResources().updateConfiguration(
            config2, getBaseContext().getResources().getDisplayMetrics());
        // loading data ...
        refresh();
        // refresh the tabs and their content
        refresh_Tab ();   
     break;
     case 201: etc...

The problem is that the MENU "shrinks" more and more everytime the user is going through the lines of code above ...

This is the Menu that gets shrunk:

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    menu.add(0, 100, 1, "REFRESH").setIcon(android.R.drawable.ic_menu_compass);
    SubMenu langMenu = menu.addSubMenu(0, 200, 2, "NL-FR").setIcon(android.R.drawable.ic_menu_rotate);
        langMenu.add(1, 201, 0, "Nederlands");
        langMenu.add(1, 202, 0, "Français");
    menu.add(0, 250, 4, R.string.OptionMenu2).setIcon(android.R.drawable.ic_menu_send);
    menu.add(0, 300, 5, R.string.OptionMenu3).setIcon(android.R.drawable.ic_menu_preferences);
    menu.add(0, 350, 3, R.string.OptionMenu4).setIcon(android.R.drawable.ic_menu_more);
    menu.add(0, 400, 6, "Exit").setIcon(android.R.drawable.ic_menu_delete);

    return super.onCreateOptionsMenu(menu);
}

What should I do in API Level 5 to make this work again ?

HERE IS THE FULL CODE IF YOU WANT TO TEST THIS :

import java.util.Locale;

import android.app.Activity;
import android.content.res.Configuration;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.SubMenu;
import android.widget.Toast;

public class Main extends Activity {
    /** Called when the activity is first created. */


    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {

        SubMenu langMenu = menu.addSubMenu(0, 200, 2, "NL-FR").setIcon(android.R.drawable.ic_menu_rotate);
            langMenu.add(1, 201, 0, "Nederlands");
            langMenu.add(1, 202, 0, "Français");

        return super.onCreateOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch(item.getItemId()){

        case 201:

            Locale locale = new Locale("nl"); 
            Locale.setDefault(locale);
            Configuration config = new Configuration();
            config.locale = locale;
            getBaseContext().getResources().updateConfiguration(config, getBaseContext().getResources().getDisplayMetrics());
            Toast.makeText(this, "Locale in Nederlands !", Toast.LENGTH_LONG).show();
            break;

        case 202:

            Locale locale2 = new Locale("fr"); 
            Locale.setDefault(locale2);
            Configuration config2 = new Configuration();
            config2.locale = locale2;
            getBaseContext().getResources().updateConfiguration(config2, getBaseContext().getResources().getDisplayMetrics());

            Toast.makeText(this, "Locale en Français !", Toast.LENGTH_LONG).show();
            break;  

        }
        return super.onOptionsItemSelected(item);
    }
}

AND HERE IS THE MANIFEST :

<?xml version="1.0" encoding="utf-8"?>
    <manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="com.cousinHub.ChangeLocale"
          android:versionCode="1"
          android:versionName="1.0">
        <application android:icon="@drawable/icon" android:label="@string/app_name">
            <activity android:name=".Main"
                      android:label="@string/app_name">
                <intent-filter>
                    <action android:name="android.intent.action.MAIN" />
                    <category android:name="android.intent.category.LAUNCHER" />
                </intent-filter>
            </activity>
        </application>
        <uses-sdk android:minSdkVersion="3" /> 
    </manifest>

THIS IS WHAT I FOUND :

<uses-sdk android:minSdkVersion="5" />

=> IT WORKS JUST FINE ...

<uses-sdk android:minSdkVersion="3" />

=> Menu shrinks every time you change the locale !!!

as I want to keep my application accessible for users on 1.5, what should I do ??

Answer

Andrey Novikov picture Andrey Novikov · Nov 21, 2010

Through the original question is not exactly about the locale itself all other locale related questions are referencing to this one. That's why I wanted to clarify the issue here. I used this question as a starting point for my own locale switching code and found out that the method is not exactly correct. It works, but only until any configuration change (e.g. screen rotation) and only in that particular Activity. Playing with a code for a while I have ended up with the following approach:

I have extended android.app.Application and added the following code:

public class MyApplication extends Application
{
    private Locale locale = null;

    @Override
    public void onConfigurationChanged(Configuration newConfig)
    {
        super.onConfigurationChanged(newConfig);
        if (locale != null)
        {
            newConfig.locale = locale;
            Locale.setDefault(locale);
            getBaseContext().getResources().updateConfiguration(newConfig, getBaseContext().getResources().getDisplayMetrics());
        }
    }

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

        SharedPreferences settings = PreferenceManager.getDefaultSharedPreferences(this);

        Configuration config = getBaseContext().getResources().getConfiguration();

        String lang = settings.getString(getString(R.string.pref_locale), "");
        if (! "".equals(lang) && ! config.locale.getLanguage().equals(lang))
        {
            locale = new Locale(lang);
            Locale.setDefault(locale);
            config.locale = locale;
            getBaseContext().getResources().updateConfiguration(config, getBaseContext().getResources().getDisplayMetrics());
        }
    }
}

This code ensures that every Activity will have custom locale set and it will not be reset on rotation and other events.

I have also spent a lot of time trying to make the preference change to be applied immediately but didn't succeed: the language changed correctly on Activity restart, but number formats and other locale properties were not applied until full application restart.

Changes to AndroidManifest.xml

Don't forget to add android:configChanges="layoutDirection|locale" to every activity at AndroidManifest, as well as the android:name=".MyApplication" to the <application> element.