让后台服务不被杀———电话录音

最近做了一个监听电话并录音的小例子，而保证它在后台运行不被杀确实不容易。

首先在主service中：

service中重写onStartCommand方法，这个方法有三个返回值， START_STICKY是service被kill掉后自动

public int onStartCommand(Intent intent, int flags, int startId) {

        IntentFilter filter=new IntentFilter();
        filter.addAction(Intent.ACTION_TIME_TICK);
        UserPresentReceive userReceive = new UserPresentReceive();
        registerReceiver(userReceive,filter);
        
        int flag = START_STICKY;
        // 判断是否是Broadcast发来的intentif (!("Protect".equals(intent.getAction()))) {
            System.out.println("action" + intent.getAction());
            this.outGoingNum = intent.getStringExtra("outGoingNums");
            // 将耗时操作放到子线程中
            backGroundExecution();
        }
        return super.onStartCommand(intent, flag, startId);
    }

 在onDestroy()方法中，启动当前服务，同时再启动protectService（）

public void onDestroy() {
        System.out.println("ServicePhone_onDestroy");
        Intent ins = new Intent(this, ServicePhone.class);
        ins.setAction("Protect");
        startService(ins);

        Intent in = new Intent(this, ProtectService.class);
        startService(in);
        super.onDestroy();
    }

新建一个ProtectService服务 ，同时再建一个broadcastReceive 

public int onStartCommand(Intent intent, int flags, int startId) {
        
        Intent ins = new Intent(this, ServicePhone.class);
        ins.setAction("Protect");
        startService(ins);
        flags = START_STICKY;
        return super.onStartCommand(intent, flags, startId);
    }

    public void onDestroy() {
        Intent in = new Intent(this, ServicePhone.class);
        in.setAction("Protect");
        startService(in);
//相互关联
        Intent ins = new Intent(this, ProtectService.class);
        startService(ins);
        super.onDestroy();
    }

 ProtectService中用alarmManager来不断触发UserPresentReceive 

private void proctectServiceInBack() {
        /**
         * 指定时间间隔 重复唤醒alarm
         */
        AlarmManager alarmManager = (AlarmManager)getSystemService(Context.ALARM_SERVICE);
        // 在合适的时间醒来
        int alarmType = AlarmManager.RTC_WAKEUP;
        // 设置时间长度
        long timeOrLengthofWait = 150;
        long timeOrLengthofWaits=20000;
        Intent intent = new Intent(getApplicationContext(),
                UserPresentReceive.class);
        intent.setAction("protect");
        PendingIntent alarmIntent = PendingIntent.getBroadcast(this, 0,
                intent, 0);
        alarmManager.setRepeating(alarmType, timeOrLengthofWait,
                timeOrLengthofWaits, alarmIntent);

    }

在UserPresentReceive 监听系统广播：

Intent.ACTION_TIME_TICK，这个广播每分钟发送一次，我们可以每分钟检查一次Service的运行状态，如果已经被结束了，就重新启动Service。
同时监听    ACTION_BOOT_COMPLETED   

    public void onReceive(Context content, Intent intent) {
        System.out.println("UserPresentReceive");
        if(Intent.ACTION_TIME_TICK.equals(intent.getAction()) ){
            Intent in=new Intent(content, ProtectService.class);
            content.startService(in);
        }else if(Intent.ACTION_BUG_REPORT.equals(intent.getAction())){
            Intent in=new Intent(content, ProtectService.class);
            content.startService(in);
        }else{
            Intent in=new Intent(content, ProtectService.class);
            content.startService(in);
        }
        //开机自启
        if(Intent.ACTION_BOOT_COMPLETED.equals(intent.getAction())){
            Intent in=new Intent(content,ServicePhone.class);
            in.setAction("Protect");
            content.startService(in);
        } else{
            Intent in=new Intent(content, ServicePhone.class);
            in.setAction("Protect");
            content.startService(in);
        }
    }

}

另外建再建一个broadcastReceive来监听电话状态

if (Intent.ACTION_NEW_OUTGOING_CALL.equals(intent.getAction())) {
            //取得号码
            String outGoingNum = intent
                    .getStringExtra(Intent.EXTRA_PHONE_NUMBER);
            Intent in=new Intent(content,ServicePhone.class);
            in.setAction(".b2");
            //将号码传给service
            in.putExtra("outGoingNums", outGoingNum);
            content.startService(in);

        } else{
            Intent in=new Intent(content, ServicePhone.class);
            in.setAction(".b3");
            content.startService(in);
        }
    }

manifest.xml    application中可以加  android:persistent="true"  提高不被杀死的几率   

<application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:persistent="true"
        android:theme="@style/AppTheme" >

 将protectService另起一个进程

<service
            android:process=":protect"
            android:name="com.example.phonelisten.ProtectService"
            android:enabled="true" >
        </service>

监听系统广播  设置android:priority 提高优先权

<receiver android:name="com.example.phonelisten.ReceivePhone" >
           <intent-filter android:priority="1000" >
               <action android:name="android.intent.action.TIME_TICK" />
                <action android:name="android.intent.action.PHONE_STATE" />
                <action android:name="android.intent.action.BOOT_COMPLETED" />
                <action android:name="android.intent.action.NEW_OUTGOING_CALL" />
            </intent-filter>
        </receiver>
        <receiver android:name="com.example.phonelisten.UserPresentReceive" >
            <intent-filter android:priority="999" >
                <action android:name="android.intent.action.BOOT_COMPLETED" />
                <action android:name="android.intent.action.TIME_TICK" />
                <action android:name="android.intent.action.BUG_REPORT" />
                 <action android:name="android.intent.action.USER_PRESENT" />
                 <action android:name="android.media.RINGER_MODE_CHANGED" />
            </intent-filter>
        </receiver>