Settings: update time zone strings on date change

If the user changes the date, most obvious case being from 1970, to a
current date, and the user's selected Locale's country time zones have
been changed (according to ICU), we must update the time zone strings in
the system.

Ref: CYNGNOS-453

Signed-off-by: Roman Birg <roman@cyngn.com>
(cherry picked from commit 926c3b0a50e521368628ef0d9975c99fa4cd3480)

Change-Id: I487c54cd4f933286c5004d24a3f8730ee2d4e4f6

3 files changed, 48 insertions, 0 deletions

diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 451f370..349bca7 100755
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -529,6 +529,13 @@
                 android:value="true" />
         </activity>
 
+        <receiver android:name=".DateChangeReceiver">
+            <intent-filter>
+                <action android:name="android.intent.action.DATE_CHANGED"/>
+                <action android:name="android.intent.action.LOCALE_CHANGED"/>
+            </intent-filter>
+        </receiver>
+
         <activity android:name="DateTimeSettingsSetupWizard"
                   android:label="@string/date_and_time"
                   android:theme="@style/Theme.DateTimeSettingsSetupWizard"
diff --git a/src/com/android/settings/DateChangeReceiver.java b/src/com/android/settings/DateChangeReceiver.java
new file mode 100644
index 0000000..6a3ec88
--- /dev/null
+++ b/src/com/android/settings/DateChangeReceiver.java
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2016 The CyanogenMod Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+
+public class DateChangeReceiver extends BroadcastReceiver {
+    @Override
+    public void onReceive(Context context, Intent intent) {
+        DateTimeSettings.updateLocaleStrings();
+    }
+}
diff --git a/src/com/android/settings/DateTimeSettings.java b/src/com/android/settings/DateTimeSettings.java
index 8a9e2ad..34753ef 100644
--- a/src/com/android/settings/DateTimeSettings.java
+++ b/src/com/android/settings/DateTimeSettings.java
@@ -40,9 +40,12 @@ import android.widget.TimePicker;
 
 import com.android.internal.logging.MetricsLogger;
 import com.android.settingslib.datetime.ZoneGetter;
+import libcore.icu.TimeZoneNames;
 
+import java.text.DateFormatSymbols;
 import java.util.Calendar;
 import java.util.Date;
+import java.util.Locale;
 
 public class DateTimeSettings extends SettingsPreferenceFragment
         implements OnSharedPreferenceChangeListener,
@@ -329,6 +332,16 @@ public class DateTimeSettings extends SettingsPreferenceFragment
         if (when / 1000 < Integer.MAX_VALUE) {
             ((AlarmManager) context.getSystemService(Context.ALARM_SERVICE)).setTime(when);
         }
+        updateLocaleStrings();
+    }
+
+    static void updateLocaleStrings() {
+        // If a device was boot up with date 1970 and then date changes to some later time,
+        // the wrong string might be cached if the country's zones have changed.
+        // See external/icu/icu4c/source/data/misc/metaZones.txt for complete mapping
+        TimeZoneNames.clearLocaleCache();
+        Locale locale = Locale.getDefault();
+        DateFormatSymbols.getInstance(locale).setZoneStrings(TimeZoneNames.getZoneStrings(locale));
     }
 
     /* package */ static void setTime(Context context, int hourOfDay, int minute) {