Andoird 监听开机广播和关机广播

需求:有时候,我们需要自己的程序在开机后自动运行;在关机时,记录一些信息到文件中.

一、开机广播监听
Android系统启动完成后会自动发出启动完成广播(android.intent.action.BOOT_COMPLETED),
所有注册了接收启动完成广播的接收器(BroadcastReceiver)都会收到此广播.

①编写一个继承BroadcastReceiver的类,接受系统启动完成广播.

 1 package com.example.systemtest;
 2
 3 import android.content.BroadcastReceiver;
 4 import android.content.Context;
 5 import android.content.Intent;
 6
 7 /**
 8  * 系统启动完成广播接收器
 9  * #<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
10  * @author Lone_Wolf
11  */
12 public class BootCompletedReceiver extends BroadcastReceiver {
13     @Override
14     public void onReceive(Context context, Intent intent) {
15         if (intent.getAction().equals(Intent.ACTION_BOOT_COMPLETED)) {
16             //example:启动程序
17             Intent start = new Intent(context, MainActivity.class);
18             start.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);//
19             context.startActivity(start);
20         }
21     }
22 }

②在AndroidManifest.xml文件里注册广播接收器.

1 <receiver android:name="com.example.systemtest.BootCompletedReceiver" >
2     <intent-filter>
3         <!-- 开机广播 -->
4         <action android:name="android.intent.action.BOOT_COMPLETED" />
5     </intent-filter>
6 </receiver>

③添加相应权限.

1 <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />

二、关机广播监听
与开机广播对应,Android系统在即将关闭时发出系统关闭广播(android.intent.action.ACTION_SHUTDOWN).

①编写一个继承BroadcastReceiver的类,接受系统关闭广播.

 1 package com.example.systemtest;
 2
 3 import java.io.File;
 4 import java.io.FileOutputStream;
 5
 6 import android.content.BroadcastReceiver;
 7 import android.content.Context;
 8 import android.content.Intent;
 9
10 /**
11  * 系统关闭广播接收器
12  * @author Lone_Wolf
13  */
14 public class ShutdownReceiver extends BroadcastReceiver {
15     @Override
16     public void onReceive(Context context, Intent intent) {
17         if (intent.getAction().equals(Intent.ACTION_SHUTDOWN)) {
18             //example:写入文件
19             FileOutputStream fos;
20             try {
21                 fos = new FileOutputStream(
22                           android.os.Environment.getExternalStorageDirectory()
23                           + File.separator + "SysLog.txt", true);
24                 fos.write("系统退出".getBytes("utf-8"));
25                 fos.close();
26             } catch (Exception e) {
27                 e.printStackTrace();
28             }
29         }
30     }
31 }

②在AndroidManifest.xml文件里注册广播接收器.

1 <receiver android:name="com.example.systemtest.ShutdownReceiver" >
2     <intent-filter>
3         <!-- 关机广播 -->
4         <action android:name="android.intent.action.ACTION_SHUTDOWN" />
5     </intent-filter>
6 </receiver>

注: onReceive中代码的执行时间不要超过5s,否则android会弹出超时dialog.
     如果需要做耗时处理,可以在onReceive()里开始一个Service,让Service去做耗时处理.
     最好不要用子线程,因为BroadcastReceiver的生命周期很短,子线程可能还没有结束BroadcastReceiver就先结束了.