Android后台定时提醒功能实现

import android.app.Activity; 
import android.content.Intent; 
import android.os.Bundle; 
import android.view.Window; 
import android.widget.Toast; 
 
public class MainActivity extends Activity { 
 
 private Intent intent; 
 @Override 
 protected void onCreate(Bundle savedInstanceState) { 
  super.onCreate(savedInstanceState); 
  //取消标题栏 
  requestWindowFeature(Window.FEATURE_NO_TITLE); 
  //由于主要是用于测试，并且便于新手理解，所以activity_main布局写的很简单 
  setContentView(R.layout.activity_main); 
  intent = new Intent(this, LongRunningService.class); 
  //开启关闭Service 
  startService(intent); 
 
  //设置一个Toast来提醒使用者提醒的功能已经开始 
  Toast.makeText(MainActivity.this,"提醒的功能已经开启，关闭界面则会取消提醒。",Toast.LENGTH_LONG).show(); 
 } 
 
 @Override 
 protected void onDestroy() { 
  super.onDestroy(); 
  //在Activity被关闭后，关闭Service 
  stopService(intent); 
 } 
} 

import android.app.AlarmManager; 
import android.app.PendingIntent; 
import android.app.Service; 
import android.content.Intent; 
import android.os.IBinder; 
import android.os.SystemClock; 
 
public class LongRunningService extends Service { 
 
 
 @Override 
 public IBinder onBind(Intent intent) { 
  return null; 
 } 
 
 @Override 
 public int onStartCommand(Intent intent, int flags, int startId) { 
 
  AlarmManager manager = (AlarmManager) getSystemService(ALARM_SERVICE); 
  //读者可以修改此处的Minutes从而改变提醒间隔时间 
  //此处是设置每隔90分钟启动一次 
  //这是90分钟的毫秒数 
  int Minutes = 90*60*1000; 
  //SystemClock.elapsedRealtime()表示1970年1月1日0点至今所经历的时间 
  long triggerAtTime = SystemClock.elapsedRealtime() + Minutes; 
  //此处设置开启AlarmReceiver这个Service 
  Intent i = new Intent(this, AlarmReceiver.class); 
  PendingIntent pi = PendingIntent.getBroadcast(this, 0, i, 0); 
  //ELAPSED_REALTIME_WAKEUP表示让定时任务的出发时间从系统开机算起，并且会唤醒CPU。 
  manager.set(AlarmManager.ELAPSED_REALTIME_WAKEUP, triggerAtTime, pi); 
  return super.onStartCommand(intent, flags, startId); 
 } 
 
 @Override 
 public void onDestroy() { 
  super.onDestroy(); 
 
  //在Service结束后关闭AlarmManager 
  AlarmManager manager = (AlarmManager) getSystemService(ALARM_SERVICE); 
  Intent i = new Intent(this, AlarmReceiver.class); 
  PendingIntent pi = PendingIntent.getBroadcast(this, 0, i, 0); 
  manager.cancel(pi); 
 
 } 
} 

import android.app.Notification; 
import android.app.NotificationManager; 
import android.content.BroadcastReceiver; 
import android.content.Context; 
import android.content.Intent; 
 
public class AlarmReceiver extends BroadcastReceiver { 
 
 @Override 
 public void onReceive(Context context, Intent intent) { 
  //设置通知内容并在onReceive()这个函数执行时开启 
  NotificationManager manager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE); 
  Notification notification=new Notification(R.drawable.ic_launcher,"用电脑时间过长了！白痴！" 
  ,System.currentTimeMillis()); 
  notification.setLatestEventInfo(context, "快去休息！！！", 
    "一定保护眼睛,不然遗传给孩子，老婆跟别人跑啊。", null); 
  notification.defaults = Notification.DEFAULT_ALL; 
  manager.notify(1, notification); 
 
 
  //再次开启LongRunningService这个服务，从而可以 
  Intent i = new Intent(context, LongRunningService.class); 
  context.startService(i); 
 } 
 
 
} 

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
 android:layout_width="match_parent" 
 android:layout_height="match_parent" 
 android:padding="15dp" 
 android:orientation="vertical" 
 > 
 
 <TextView 
  android:layout_marginBottom="20dp" 
  android:layout_width="match_parent" 
  android:layout_height="wrap_content" 
  android:text="护眼定时提醒" 
  android:textSize="30sp" 
  android:gravity="center_horizontal" 
  /> 
  
 
 <TextView 
  android:layout_width="match_parent" 
  android:layout_height="wrap_content" 
  android:text="提醒间隔时间:" 
  android:textSize="25sp" 
  /> 
 
 <TextView 
  android:layout_width="match_parent" 
  android:layout_height="wrap_content" 
  android:text="90分钟" 
  android:textSize="25sp" 
  /> 
 
 <TextView 
  android:layout_width="match_parent" 
  android:layout_height="wrap_content" 
  android:text="提醒音乐：" 
  android:textSize="25sp" 
  /> 
 <TextView 
  android:layout_width="match_parent" 
  android:layout_height="wrap_content" 
  android:text="系统默认音乐" 
  android:textSize="25sp" 
  /> 
</LinearLayout> 

<?xml version="1.0" encoding="utf-8"?> 
<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
 package="com.example.servicebestpractice" 
 android:versionCode="1" 
 android:versionName="1.0" > 
 
 <uses-sdk 
  android:minSdkVersion="14" 
  android:targetSdkVersion="17" /> 
 
 <application 
  android:allowBackup="true" 
  android:icon="@drawable/ic_launcher" 
  android:label="@string/app_name" 
  android:theme="@style/AppTheme" > 
  <activity 
   android:name="com.example.servicebestpractice.MainActivity" 
   android:label="@string/app_name" > 
   <intent-filter> 
    <action android:name="android.intent.action.MAIN" /> 
 
    <category android:name="android.intent.category.LAUNCHER" /> 
   </intent-filter> 
  </activity> 
 
  <service android:name=".LongRunningService" > 
  </service> 
 
  <receiver android:name=".AlarmReceiver" > 
  </receiver> 
 </application> 
 
</manifest>