您必须使用一项服务。 ApiDemos 中有一个完整的示例 - 名称为 AlarmService_Service 和 AlarmService。我将在这里为您发布代码：
/*
* Copyright (C) 2007 The Android Open Source 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.example.android.apis.app;
// Need the following import to get access to the app resources, since this
// class is in a sub-package.
import com.example.android.apis.R;
import android.app.Activity;
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.Intent;
import android.os.SystemClock;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;
/**
* This demonstrates how you can schedule an alarm that causes a service to
* be started. This is useful when you want to schedule alarms that initiate
* long-running operations, such as retrieving recent e-mails.
*/
public class AlarmService extends Activity {
private PendingIntent mAlarmSender;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Create an IntentSender that will launch our service, to be scheduled
// with the alarm manager.
mAlarmSender = PendingIntent.getService(AlarmService.this,
0, new Intent(AlarmService.this, AlarmService_Service.class), 0);
setContentView(R.layout.alarm_service);
// Watch for button clicks.
Button button = (Button)findViewById(R.id.start_alarm);
button.setOnClickListener(mStartAlarmListener);
button = (Button)findViewById(R.id.stop_alarm);
button.setOnClickListener(mStopAlarmListener);
}
private OnClickListener mStartAlarmListener = new OnClickListener() {
public void onClick(View v) {
// We want the alarm to go off 30 seconds from now.
long firstTime = SystemClock.elapsedRealtime();
// Schedule the alarm!
AlarmManager am = (AlarmManager)getSystemService(ALARM_SERVICE);
am.setRepeating(AlarmManager.ELAPSED_REALTIME_WAKEUP,
firstTime, 30*1000, mAlarmSender);
// Tell the user about what we did.
Toast.makeText(AlarmService.this, R.string.repeating_scheduled,
Toast.LENGTH_LONG).show();
}
};
private OnClickListener mStopAlarmListener = new OnClickListener() {
public void onClick(View v) {
// And cancel the alarm.
AlarmManager am = (AlarmManager)getSystemService(ALARM_SERVICE);
am.cancel(mAlarmSender);
// Tell the user about what we did.
Toast.makeText(AlarmService.this, R.string.repeating_unscheduled,
Toast.LENGTH_LONG).show();
}
};
}
和服务：
/*
* Copyright (C) 2007 The Android Open Source 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.example.android.apis.app;
// Need the following import to get access to the app resources, since this
// class is in a sub-package.
import com.example.android.apis.R;
import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.Service;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
import android.os.Parcel;
import android.os.RemoteException;
import android.widget.Toast;
/**
* This is an example of implementing an application service that will run in
* response to an alarm, allowing us to move long duration work out of an
* intent receiver.
*
* @see AlarmService
* @see AlarmService_Alarm
*/
public class AlarmService_Service extends Service {
NotificationManager mNM;
@Override
public void onCreate() {
mNM = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
// show the icon in the status bar
showNotification();
// Start up the thread running the service. Note that we create a
// separate thread because the service normally runs in the process's
// main thread, which we don't want to block.
Thread thr = new Thread(null, mTask, "AlarmService_Service");
thr.start();
}
@Override
public void onDestroy() {
// Cancel the notification -- we use the same ID that we had used to start it
mNM.cancel(R.string.alarm_service_started);
// Tell the user we stopped.
Toast.makeText(this, R.string.alarm_service_finished, Toast.LENGTH_SHORT).show();
}
/**
* The function that runs in our worker thread
*/
Runnable mTask = new Runnable() {
public void run() {
// Normally we would do some work here... for our sample, we will
// just sleep for 30 seconds.
long endTime = System.currentTimeMillis() + 15*1000;
while (System.currentTimeMillis() < endTime) {
synchronized (mBinder) {
try {
mBinder.wait(endTime - System.currentTimeMillis());
} catch (Exception e) {
}
}
}
// Done with our work... stop the service!
AlarmService_Service.this.stopSelf();
}
};
@Override
public IBinder onBind(Intent intent) {
return mBinder;
}
/**
* Show a notification while this service is running.
*/
private void showNotification() {
// In this sample, we'll use the same text for the ticker and the expanded notification
CharSequence text = getText(R.string.alarm_service_started);
// Set the icon, scrolling text and timestamp
Notification notification = new Notification(R.drawable.stat_sample, text,
System.currentTimeMillis());
// The PendingIntent to launch our activity if the user selects this notification
PendingIntent contentIntent = PendingIntent.getActivity(this, 0,
new Intent(this, AlarmService.class), 0);
// Set the info for the views that show in the notification panel.
notification.setLatestEventInfo(this, getText(R.string.alarm_service_label),
text, contentIntent);
// Send the notification.
// We use a layout id because it is a unique number. We use it later to cancel.
mNM.notify(R.string.alarm_service_started, notification);
}
/**
* This is the object that receives interactions from clients. See RemoteService
* for a more complete example.
*/
private final IBinder mBinder = new Binder() {
@Override
protected boolean onTransact(int code, Parcel data, Parcel reply,
int flags) throws RemoteException {
return super.onTransact(code, data, reply, flags);
}
};
}
