如何像QQ一样进程不被系统杀死
2018-01-29 香沙小熊 代码集中营
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今天介绍一个android的Service，他是一个后台服务，专门用来处理常驻后台的工作组件。我们用的即时通讯，service来做常驻后台
进程优先级
进程的重要性优先级：
1. 前台进程：Foreground process
用户正在交互的Activity（onResume()
当某个Service绑定正在交互的Activity
被主动调用为前台的Service(startForeground())
组件正在执行生命周期的回调（(onCreate() /onStart()/onDestory())
BroadcastReceiver 正在执行onReceive()；
2.可见进程：Visible process
我们的Activity处在onPause() (没有进入onStop())
绑定到前台Activity的Service
3.服务进程：Service process
简单的startservice()启动
4.后台进程：Background process
对用户没有直接影响的进程-----Activity处于onStop()的时候
5.空进程 ：Empty process
不含有任何的活动的组件。(android设计的，为了第二次启动更快，采取了一个权衡)
进程越往后越容易被系统杀死
如何不被系统杀死
我们要如何提升进程的优先级(尽量做到不轻易被系统杀死)，提供以下七个方案
1. 模仿QQ采取在锁屏的时候启动1个像素的Activity。
背景：当手机锁屏的时候什么都干死了，为了省电。
监听锁屏广播，锁了---启动这个1像素Activity。
监听锁屏的， 开启---结束掉这个1像素Activity。
要监听锁屏的广播---动态注册。
关键代码：
publicclassKeepLiveActivityManager{
privatestaticKeepLiveActivityManager instance;
privateContext context;
privateWeakReference activityInstance;
publicstaticKeepLiveActivityManagergetInstance(Context context){
if(instance==null){
instance =newKeepLiveActivityManager(context.getApplicationContext());
}
returninstance;
}
privateKeepLiveActivityManager(Context context){
this.context = context;
}
publicvoidsetKeepLiveActivity(Activity activity){
activityInstance =newWeakReference(activity);
}
publicvoidstartKeepLiveActivity(){
Intent intent =newIntent(context, KeepLiveActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(intent);
}
publicvoidfinishKeepLiveActivity(){
if(activityInstance!=null&&activityInstance.get()!=null){
Activity activity = activityInstance.get();
activity.finish();
} }
}
源码地址：https://github.com/kpioneer123/KeepLiveProcess
2. 大型App运营商和手机厂商可能有合作关系---白名单
3. 双进程守护
一个进程被杀死，另外一个进程又被他启动，相互监听启动。
A<---->B
杀进程是一个一个杀的，本质是和杀进程时间赛跑。
关键代码：
publicclassLocalServiceextendsService{
publicstaticfinalString ACTION_LOCAL_SERVICE ="com.haocai.app.keepliveprocess.LocalService";
privatestaticfinalString TAG ="LocalService";
privateMyServiceConnection conn;
privateMyBinder binder;
privateIntent testIntent;
@Override
publicvoidonCreate(){
// TODO Auto-generated method stub
super.onCreate();
if(binder ==null){
binder =newMyBinder();
}
conn =newMyServiceConnection();
}
@Nullable
@Override
publicIBinderonBind(Intent intent){
returnbinder;
}
@Override
publicvoidonDestroy(){
super.onDestroy();
if(testIntent!=null){
stopService(testIntent);
}
//unbindService(conn);
}
//启动前台进程 增加重要性优先级
@Override
publicintonStartCommand(Intent intent,intflags,intstartId){
LocalService.this.bindService(newIntent(LocalService.this, RemoteService.class), conn, Context.BIND_IMPORTANT);
PendingIntent contentIntent = PendingIntent.getService(this,0, intent,0);
NotificationCompat.Builder builder =newNotificationCompat.Builder(this);
builder.setTicker("360")
.setContentIntent(contentIntent)
.setContentTitle("我是360，我怕谁!")
.setAutoCancel(true)
.setContentText("hehehe")
.setWhen( System.currentTimeMillis());
//把service设置为前台运行，避免手机系统自动杀掉改服务。
startForeground(startId, builder.build());
returnSTART_STICKY;
}
classMyBinderextendsRemoteConnection.Stub{
@Override
publicStringgetProcessName()throwsRemoteException{
// TODO Auto-generated method stub
return"LocalService";
}
}
classMyServiceConnectionimplementsServiceConnection{
@Override
publicvoidonServiceConnected(ComponentName name, IBinder service){
Log.i(TAG,"建立连接成功！");
}
@Override
publicvoidonServiceDisconnected(ComponentName name){
Log.i(TAG,"本地服务被干掉了~~~~~断开连接!");
Toast.makeText(LocalService.this,"断开连接", Toast.LENGTH_SHORT).show();
//启动被干掉的
testIntent =newIntent();
//自定义的Service的action
testIntent.setAction(RemoteService.ACTION_REMOTE_SERVICE);
//自定义Service的包名
testIntent.setPackage(getPackageName());
Log.i("999", getPackageName() +"");
startService(testIntent);
LocalService.this.bindService(newIntent(LocalService.this, RemoteService.class), conn, Context.BIND_IMPORTANT);
}
}
}
源码地址：https://github.com/kpioneer123/KeepLiveProcess2
4. JobScheduler
把任务加到系统调度队列中，当到达任务窗口期的时候就会执行，我们可以在这个任务里面启动我们的进程。这样可以做到将近杀不死的进程。
@SuppressLint("NewApi")
publicclassJobHandleServiceextendsJobService{
publicstaticfinalString ACTION_JOB_HANDLE_SERVICE ="com.haocai.app.keepliveprocess.JobHandleService";
privateintkJobId =0;
@Override
publicvoidonCreate(){
super.onCreate();
Log.i("INFO","jobService create");
}
@Override
publicintonStartCommand(Intent intent,intflags,intstartId){
Log.i("INFO","jobService start");
scheduleJob(getJobInfo());
returnSTART_NOT_STICKY;
}
@Override
publicvoidonDestroy(){
// TODO Auto-generated method stub
super.onDestroy();
}
@Override
publicbooleanonStartJob(JobParameters params){
// TODO Auto-generated method stub
Log.i("INFO","job start");
// scheduleJob(getJobInfo());
booleanisLocalServiceWork = isServiceWork(this, LocalService.ACTION_LOCAL_SERVICE);
booleanisRemoteServiceWork = isServiceWork(this, RemoteService.ACTION_REMOTE_SERVICE);
// Log.i("INFO", "localSericeWork:"+isLocalServiceWork);
// Log.i("INFO", "remoteSericeWork:"+isRemoteServiceWork);
if(!isLocalServiceWork||
!isRemoteServiceWork){
//this.startService(new Intent(this,LocalService.class));
startLocalService();
startRemoteService();
//this.startService(new Intent(this,RemoteService.class));
Toast.makeText(this,"process start", Toast.LENGTH_SHORT).show();
}
returntrue;
}
privatevoidstartLocalService(){
Intent testIntent =newIntent();
//自定义的Service的action
testIntent.setAction(LocalService.ACTION_LOCAL_SERVICE);
//自定义Service的包名
testIntent.setPackage(getPackageName());
Log.i("999",getPackageName()+"");
startService(testIntent);
}
privatevoidstartRemoteService(){
Intent testIntent =newIntent();
//自定义的Service的action
testIntent.setAction(RemoteService.ACTION_REMOTE_SERVICE);
//自定义Service的包名
testIntent.setPackage(getPackageName());
Log.i("999", getPackageName() +"");
startService(testIntent);
}
@Override
publicbooleanonStopJob(JobParameters params){
Log.i("INFO","job stop");
// Toast.makeText(this, "process stop", Toast.LENGTH_SHORT).show();
scheduleJob(getJobInfo());
returntrue;
}
/** Send job to the JobScheduler. */
publicvoidscheduleJob(JobInfo t){
Log.i("INFO","Scheduling job");
JobScheduler tm =
(JobScheduler) getSystemService(Context.JOB_SCHEDULER_SERVICE);
tm.schedule(t);
}
publicJobInfogetJobInfo(){
JobInfo.Builder builder =newJobInfo.Builder(kJobId++,newComponentName(this, JobHandleService.class));
builder.setRequiredNetworkType(JobInfo.NETWORK_TYPE_ANY);
builder.setPersisted(true);
builder.setRequiresCharging(false);
builder.setRequiresDeviceIdle(false);
builder.setPeriodic(10);//间隔时间--周期
returnbuilder.build();
}
/**
* 判断某个服务是否正在运行的方法
*
*@parammContext
*@paramserviceName
* 是包名+服务的类名（例如：net.loonggg.testbackstage.TestService）
*@returntrue代表正在运行，false代表服务没有正在运行
*/
publicbooleanisServiceWork(Context mContext, String serviceName){
booleanisWork =false;
ActivityManager myAM = (ActivityManager) mContext
.getSystemService(Context.ACTIVITY_SERVICE);
List myList = myAM.getRunningServices(100);
if(myList.size() <=0) {
returnfalse;
}
for(inti =0; i < myList.size(); i++) {
String mName = myList.get(i).service.getClassName().toString();
if(mName.equals(serviceName)) {
isWork =true;
break;
}
}
returnisWork;
}
}
5. 监听QQ,微信，系统应用，友盟，小米推送等等的广播，然后把自己启动了。
6. 利用账号同步机制唤醒我们的进程AccountManager
7. NDK来解决，Native进程来实现双进程守护。