gecko-dev/mobile/android/base/LocaleManager.java

217 lines
7.1 KiB
Java
Raw Normal View History

/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
package org.mozilla.gecko;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.SharedPreferences;
import android.content.res.Configuration;
import android.content.res.Resources;
import android.util.Log;
import java.util.Locale;
/**
* This class manages persistence, application, and otherwise handling of
* user-specified locales.
*
* Of note:
*
* * It's a singleton, because its scope extends to that of the application,
* and definitionally all changes to the locale of the app must go through
* this.
* * It's lazy.
* * It has ties into the Gecko event system, because it has to tell Gecko when
* to switch locale.
* * It relies on using the SharedPreferences file owned by the browser (in
* Fennec's case, "GeckoApp") for performance.
*/
public class LocaleManager {
private static final String LOG_TAG = "GeckoLocales";
// These are both volatile because we don't impose restrictions
// over which thread calls our methods.
private static volatile ContextGetter getter = null;
private static volatile Locale currentLocale = null;
private static volatile boolean inited = false;
private static boolean systemLocaleDidChange = false;
private static BroadcastReceiver receiver;
public static void setContextGetter(ContextGetter getter) {
Log.d(LOG_TAG, "Calling setContextGetter: " + getter);
LocaleManager.getter = getter;
}
public static void initialize() {
if (inited) {
return;
}
receiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
systemLocaleDidChange = true;
}
};
getContext().registerReceiver(receiver, new IntentFilter(Intent.ACTION_LOCALE_CHANGED));
inited = true;
}
public static boolean systemLocaleDidChange() {
return systemLocaleDidChange;
}
private static Context getContext() {
if (getter == null) {
throw new IllegalStateException("No ContextGetter; cannot fetch context.");
}
return getter.getContext();
}
private static SharedPreferences getSharedPreferences() {
if (getter == null) {
throw new IllegalStateException("No ContextGetter; cannot fetch prefs.", new RuntimeException("No prefs."));
}
return getter.getSharedPreferences();
}
/**
* Every time the system gives us a new configuration, it
* carries the external locale. Fix it.
*/
public static void correctLocale(Resources res, Configuration config) {
Locale current = getCurrentLocale();
if (current == null) {
return;
}
// I know it's tempting to short-circuit here if the config seems to be
// up-to-date, but the rest is necessary.
config.locale = current;
// The following two lines are heavily commented in case someone
// decides to chase down performance improvements and decides to
// question what's going on here.
// Both lines should be cheap, *but*...
// This is unnecessary for basic string choice, but it almost
// certainly comes into play when rendering numbers, deciding on RTL,
// etc. Take it out if you can prove that's not the case.
Locale.setDefault(current);
// This seems to be a no-op, but every piece of documentation under the
// sun suggests that it's necessary, and it certainly makes sense.
res.updateConfiguration(config, res.getDisplayMetrics());
}
private static Locale parseLocaleCode(final String localeCode) {
int index;
if ((index = localeCode.indexOf('-')) != -1 ||
(index = localeCode.indexOf('_')) != -1) {
final String langCode = localeCode.substring(0, index);
final String countryCode = localeCode.substring(index + 1);
return new Locale(langCode, countryCode);
} else {
return new Locale(localeCode);
}
}
public static Locale getCurrentLocale() {
if (currentLocale != null) {
return currentLocale;
}
final String current = getPersistedLocale();
if (current == null) {
return null;
}
return currentLocale = parseLocaleCode(current);
}
/**
* Returns the persisted locale if it differed from the current.
*/
public static String updateLocale(String localeCode) {
// Fast path.
final Locale defaultLocale = Locale.getDefault();
if (defaultLocale.toString().equals(localeCode)) {
return null;
}
final Locale locale = parseLocaleCode(localeCode);
// Fast path.
if (defaultLocale.equals(locale)) {
return null;
}
Locale.setDefault(locale);
currentLocale = locale;
// Update resources.
Resources res = getContext().getResources();
Configuration config = res.getConfiguration();
config.locale = locale;
res.updateConfiguration(config, res.getDisplayMetrics());
// Tell Gecko.
GeckoEvent ev = GeckoEvent.createBroadcastEvent("Locale:Changed", locale.toString());
GeckoAppShell.sendEventToGecko(ev);
return locale.toString();
}
private static String getPrefName() {
return getContext().getPackageName() + ".locale";
}
public static String getPersistedLocale() {
final SharedPreferences settings = getSharedPreferences();
// N.B., it is expected that any per-profile settings will be
// implemented via SharedPreferences multiplexing in ContextGetter, not
// via profile-annotated preference names.
final String locale = settings.getString(getPrefName(), "");
if ("".equals(locale)) {
return null;
}
return locale;
}
private static void persistLocale(String localeCode) {
final SharedPreferences settings = getSharedPreferences();
settings.edit().putString(getPrefName(), localeCode).commit();
}
public static String getAndApplyPersistedLocale() {
final long t1 = android.os.SystemClock.uptimeMillis();
final String localeCode = getPersistedLocale();
if (localeCode == null) {
return null;
}
updateLocale(localeCode);
final long t2 = android.os.SystemClock.uptimeMillis();
Log.i(LOG_TAG, "Locale read and update took: " + (t2 - t1) + "ms.");
return localeCode;
}
/**
* Returns the set locale if it changed. Always persists.
*/
public static String setSelectedLocale(String localeCode) {
final String resultant = updateLocale(localeCode);
persistLocale(localeCode);
return resultant;
}
}