Java tutorial
/* * Copyright 2013 Google Inc. * * 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.google.android.apps.dashclock; import android.app.AlarmManager; import android.app.PendingIntent; import android.content.Context; import android.content.Intent; import android.os.SystemClock; import android.support.v4.content.WakefulBroadcastReceiver; import com.google.android.apps.dashclock.api.DashClockExtension; import static com.google.android.apps.dashclock.LogUtils.LOGD; import static com.google.android.apps.dashclock.Utils.MINUTES_MILLIS; /** * A broadcast receiver in charge of scheduling DashClock extension refreshes. This was * originally handled by updatePeriodMillis but custom refresh behavior and a separation of * extension refreshes from widget refreshes was desirable so was moved here. */ public class PeriodicExtensionRefreshReceiver extends WakefulBroadcastReceiver { private static final String TAG = LogUtils.makeLogTag(PeriodicExtensionRefreshReceiver.class); private static final String ACTION_PERIODIC_ALARM = "com.google.android.apps.dashclock.action.PERIODIC_ALARM"; @Override public void onReceive(Context context, Intent intent) { if (intent == null || !ACTION_PERIODIC_ALARM.equals(intent.getAction())) { return; } // Periodic alarm has triggered. Update all extensions. startWakefulService(context, getUpdateAllExtensionsIntent(context, DashClockExtension.UPDATE_REASON_PERIODIC)); } private static Intent getUpdateAllExtensionsIntent(Context context, int reason) { LOGD(TAG, "getUpdateAllExtensionsIntent, reason=" + reason); return new Intent(context, DashClockService.class).setAction(DashClockService.ACTION_UPDATE_EXTENSIONS) .putExtra(DashClockService.EXTRA_UPDATE_REASON, reason); } /** * Sets the refresh schedule if one isn't set already. */ public static void updateExtensionsAndEnsurePeriodicRefresh(final Context context) { LOGD(TAG, "updateExtensionsAndEnsurePeriodicRefresh"); AlarmManager am = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE); // Update all extensions now. context.startService(getUpdateAllExtensionsIntent(context, DashClockExtension.UPDATE_REASON_MANUAL)); // Schedule an alarm for every 30 minutes; it will not wake up the device; // it will be handled only once the device is awake. The first time that this // alarm can go off is in 15 minutes, and the latest time it will go off is // 45 minutes from now. PendingIntent pi = PendingIntent.getBroadcast(context, 0, new Intent(context, PeriodicExtensionRefreshReceiver.class).setAction(ACTION_PERIODIC_ALARM), PendingIntent.FLAG_UPDATE_CURRENT); am.cancel(pi); am.setInexactRepeating(AlarmManager.ELAPSED_REALTIME_WAKEUP, SystemClock.elapsedRealtime() + 15 * MINUTES_MILLIS, AlarmManager.INTERVAL_HALF_HOUR, pi); } /** * Cancels the refresh schedule if one isn't set already. */ protected static void cancelPeriodicRefresh(final Context context) { final AlarmManager am = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE); PendingIntent pi = PendingIntent.getBroadcast(context, 0, new Intent(context, PeriodicExtensionRefreshReceiver.class).setAction(ACTION_PERIODIC_ALARM), PendingIntent.FLAG_CANCEL_CURRENT); am.cancel(pi); } }