Listen for weather update notifications instead of polling.

DeskClock still periodically requests updated information
from the weather content provider (as recommended by the
Genie team) but does so on an hourly schedule rather than
every 5 minutes.

Also addresses http://b/2314820.

diff --git a/src/com/android/deskclock/DeskClock.java b/src/com/android/deskclock/DeskClock.java
index cfb599e..2df4d0b 100644 (file)
--- a/src/com/android/deskclock/DeskClock.java
+++ b/src/com/android/deskclock/DeskClock.java
@@ -29,6 +29,7 @@ import android.content.SharedPreferences;
 import android.content.pm.PackageManager;
 import android.content.res.Configuration;
 import android.content.res.Resources;
+import android.database.ContentObserver;
 import android.database.Cursor;
 import android.graphics.drawable.BitmapDrawable;
 import android.graphics.drawable.ColorDrawable;
@@ -94,13 +95,11 @@ public class DeskClock extends Activity {
     // Alarm action for midnight (so we can update the date display).
     private static final String ACTION_MIDNIGHT = "com.android.deskclock.MIDNIGHT";
 
-    // Interval between polls of the weather widget. Its refresh period is
-    // likely to be much longer (~3h), but we want to pick up any changes
-    // within 5 minutes.
-    private final long QUERY_WEATHER_DELAY = 5 * 60 * 1000; // 5 min
+    // Interval between forced polls of the weather widget.
+    private final long QUERY_WEATHER_DELAY = 60 * 60 * 1000; // 1 hr
 
     // Delay before engaging the burn-in protection mode (green-on-black).
-    private final long SCREEN_SAVER_TIMEOUT = 5* 60 * 1000; // 10 min
+    private final long SCREEN_SAVER_TIMEOUT = 5 * 60 * 1000; // 5 min
 
     // Repositioning delay in screen saver.
     private final long SCREEN_SAVER_MOVE_DELAY = 60 * 1000; // 1 min
@@ -211,6 +210,14 @@ public class DeskClock extends Activity {
         }
     };
 
+    private final ContentObserver mContentObserver = new ContentObserver(mHandy) {
+        @Override
+        public void onChange(boolean selfChange) {
+            if (DEBUG) Log.d(LOG_TAG, "content observer notified that weather changed");
+            refreshWeather();
+        }
+    };
+
 
     private void moveScreenSaver() {
         moveScreenSaverTo(-1,-1);
@@ -342,8 +349,7 @@ public class DeskClock extends Activity {
     private void requestWeatherDataFetch() {
         if (DEBUG) Log.d(LOG_TAG, "forcing the Genie widget to update weather now...");
         sendBroadcast(new Intent(ACTION_GENIE_REFRESH).putExtra("requestWeather", true));
-        // update the display with any new data
-        scheduleWeatherQueryDelayed(5000);
+        // we expect the result to show up in our content observer
     }
 
     private boolean supportsWeather() {
@@ -562,6 +568,16 @@ public class DeskClock extends Activity {
         filter.addAction(ACTION_MIDNIGHT);
         registerReceiver(mIntentReceiver, filter);
 
+        // Listen for updates to weather data
+        Uri weatherNotificationUri = new Uri.Builder()
+            .scheme(android.content.ContentResolver.SCHEME_CONTENT)
+            .authority(WEATHER_CONTENT_AUTHORITY)
+            .path(WEATHER_CONTENT_PATH)
+            .build();
+        getContentResolver().registerContentObserver(
+            weatherNotificationUri, true, mContentObserver);
+
+        // Elaborate mechanism to find out when the day rolls over
         Calendar today = Calendar.getInstance();
         today.add(Calendar.DATE, 1);
         mMidnightIntent = PendingIntent.getBroadcast(this, 0, new Intent(ACTION_MIDNIGHT), 0);
@@ -602,6 +618,8 @@ public class DeskClock extends Activity {
 
         // Other things we don't want to be doing in the background.
         unregisterReceiver(mIntentReceiver);
+        getContentResolver().unregisterContentObserver(mContentObserver);
+
         AlarmManager am = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
         am.cancel(mMidnightIntent);
         unscheduleWeatherQuery();