最近针对我们项目中app经常收不到推送的问题作了一些处理，增加app的保活管理。我们知道当安卓进程退到后台之后，很容易被系统杀死，这个时候推送消息一般都是收不到的。我也观察了一些比较主流的app,像同花顺，钉钉，甚至是支付宝我都很少在后台收到过消息，尤其是支付宝计步功能老是不准，很有可能就是这种问题导致的
当然没有百分之百可以实现保活的解决方案，即便是从ndk层面去进行，但至少我们要尽一些努力，我采用的是双进程守护+1像素Activity的实现方式
双进程守护：
开启两个service，分别在两个进程中运行，启动一个service时，通过aidl的方式将它和另一个service绑定在一起，当其中一个service被杀掉的时候，另一个service中重新将它启动
service1启动绑定service2
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
//提高进程优先级
startForeground(GuardServiceId2,new Notification());
//绑定建立链接
bindService(new Intent(getApplicationContext(),GuardService2.class),connection, Context.BIND_IMPORTANT);
return START_STICKY;
}
service1和service2的链接断开时，说明service2被杀死，这时重新绑定
private ServiceConnection connection = new ServiceConnection() {
@Override
public void onServiceConnected(ComponentName componentName, IBinder iBinder) {
ArLog.i("TAG", "connect to guardservice2");
}
@Override
public void onServiceDisconnected(ComponentName componentName) {
// 断开链接 ,重新启动，重新绑定
startService(new Intent(getApplicationContext(), GuardService2.class));
bindService(new Intent(getApplicationContext(),GuardService2.class),connection, Context.BIND_IMPORTANT);
ArLog.i("TAG", "disconnect from guardservice2");
}
};
service2绑定service1的逻辑同上
这样一来，基本上在一定程度上可以保证app常驻内存了，保险起见，我们再加一层保护，创建两个JobService
分别位于上边两个进程中（安卓5.0以上适用），开启一个轮巡任务不断的检查service存活情况，如果不在了，启动它，注意JobService需要权限
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
// 开启一个轮寻
JobScheduler jobScheduler = (JobScheduler) getSystemService(Context.JOB_SCHEDULER_SERVICE);
JobInfo.Builder jobBuilder = new JobInfo.Builder(jobId,new ComponentName(this,JobWakeUpService1.class));
//设置每两秒钟一次
jobBuilder.setPeriodic(2000);
jobScheduler.schedule(jobBuilder.build());
ArLog.i("TAG", "start JobWakeUpService1");
return START_STICKY;
}
@Override
public boolean onStartJob(JobParameters jobParameters) {
// 开启定时任务，定时轮寻 ， 看MessageService有没有被杀死
// 如果杀死了启动 轮寻onStartJob
// 判断服务有没有在运行
boolean messageServiceAlive = serviceAlive(GuardService1.class.getName());
if(!messageServiceAlive){
ArLog.i("TAG", "GuardService1 is killed ，restart it");
startService(new Intent(this,GuardService1.class));
}
boolean JobWakeUpService2Alive = serviceAlive(JobWakeUpService2.class.getName());
if(!JobWakeUpService2Alive){
ArLog.i("TAG", "JobWakeUpService2 is killed ，restart it");
startService(new Intent(this,JobWakeUpService2.class));
}
return false;
}
1像素Activity：
监听系统锁屏消息，在屏幕锁定的时候开启一个Activity，这个Activity只有一个像素大小，当屏幕开启的时候再关闭这个Activity，达到app一直位于前台进程的目的，提高进程的优先级，降低系统杀死app的概率,在这个Activity启动时设置app只有一个像素大小，既可以减少占用空间，也可以防止开锁屏期间被用户发现这个奇怪的页面
Window window = getWindow();
window.setGravity(Gravity.LEFT & Gravity.TOP);
WindowManager.LayoutParams attributes = window.getAttributes();
attributes.x = 0;
attributes.y = 0;
attributes.width = 1;
attributes.height = 1;
window.setAttributes(attributes);
在AndroidManifest中配置
完整代码：
GuardService1
public class GuardService1 extends Service {
private final int GuardServiceId2 = 2;
@Override
public void onCreate() {
super.onCreate();
ArLog.i("TAG", "GuardService1 wait for signal");
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
//提高进程优先级
startForeground(GuardServiceId2,new Notification());
//绑定建立链接
bindService(new Intent(getApplicationContext(),GuardService2.class),connection, Context.BIND_IMPORTANT);
return START_STICKY;
}
@Override
public IBinder onBind(Intent intent) {
return new GuardAIDL.Stub(){};
}
private ServiceConnection connection = new ServiceConnection() {
@Override
public void onServiceConnected(ComponentName componentName, IBinder iBinder) {
ArLog.i("TAG", "connect to guardservice2");
}
@Override
public void onServiceDisconnected(ComponentName componentName) {
// 断开链接 ,重新启动，重新绑定
startService(new Intent(getApplicationContext(), GuardService2.class));
bindService(new Intent(getApplicationContext(),GuardService2.class),connection, Context.BIND_IMPORTANT);
ArLog.i("TAG", "disconnect from guardservice2");
}
};
@Override
public void onDestroy() {
ArLog.i("TAG", "guardservice2 is onDestroy");
unbindService(connection);
super.onDestroy();
}
}
GuardService2
public class GuardService2 extends Service {
private final int GuardServiceId1 = 1;
@Override
public void onCreate() {
super.onCreate();
ArLog.i("TAG", "GuardService2 wait for signal");
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
//提高进程优先级
startForeground(GuardServiceId1,new Notification());
//绑定建立链接
bindService(new Intent(getApplicationContext(),GuardService1.class),connection, Context.BIND_IMPORTANT);
return START_STICKY;
}
@Override
public IBinder onBind(Intent intent) {
return new GuardAIDL.Stub(){};
}
private ServiceConnection connection = new ServiceConnection() {
@Override
public void onServiceConnected(ComponentName componentName, IBinder iBinder) {
ArLog.i("TAG", "connect to guardservice1");
}
@Override
public void onServiceDisconnected(ComponentName componentName) {
// 断开链接 ,重新启动，重新绑定
startService(new Intent(getApplicationContext(), GuardService1.class));
bindService(new Intent(getApplicationContext(),GuardService1.class),connection, Context.BIND_IMPORTANT);
ArLog.i("TAG", "disconnect from guardservice1");
}
};
@Override
public void onDestroy() {
ArLog.i("TAG", "guardservice1 is onDestroy");
unbindService(connection);
super.onDestroy();
}
}
JobWakeUpService1
@RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
public class JobWakeUpService1 extends JobService {
private int jobId = 12;
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
// 开启一个轮寻
JobScheduler jobScheduler = (JobScheduler) getSystemService(Context.JOB_SCHEDULER_SERVICE);
JobInfo.Builder jobBuilder = new JobInfo.Builder(jobId,new ComponentName(this,JobWakeUpService1.class));
//设置每两秒钟一次
jobBuilder.setPeriodic(2000);
jobScheduler.schedule(jobBuilder.build());
ArLog.i("TAG", "start JobWakeUpService1");
return START_STICKY;
}
@Override
public boolean onStartJob(JobParameters jobParameters) {
// 开启定时任务，定时轮寻 ， 看MessageService有没有被杀死
// 如果杀死了启动 轮寻onStartJob
// 判断服务有没有在运行
boolean messageServiceAlive = serviceAlive(GuardService1.class.getName());
if(!messageServiceAlive){
ArLog.i("TAG", "GuardService1 is killed ，restart it");
startService(new Intent(this,GuardService1.class));
}
boolean JobWakeUpService2Alive = serviceAlive(JobWakeUpService2.class.getName());
if(!JobWakeUpService2Alive){
ArLog.i("TAG", "JobWakeUpService2 is killed ，restart it");
startService(new Intent(this,JobWakeUpService2.class));
}
return false;
}
@Override
public boolean onStopJob(JobParameters jobParameters) {
return false;
}
/**
* 判断某个服务是否正在运行的方法
* @param serviceName
* 是包名+服务的类名（例如：net.loonggg.testbackstage.TestService）
* @return true代表正在运行，false代表服务没有正在运行
*/
private boolean serviceAlive(String serviceName) {
boolean isWork = false;
ActivityManager myAM = (ActivityManager)getSystemService(Context.ACTIVITY_SERVICE);
List myList = myAM.getRunningServices(100);
if (myList.size() <= 0) {
return false;
}
for (int i = 0; i < myList.size(); i++) {
String mName = myList.get(i).service.getClassName().toString();
if (mName.equals(serviceName)) {
isWork = true;
break;
}
}
return isWork;
}
}
JobWakeUpService2
@RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
public class JobWakeUpService2 extends JobService {
private int jobId = 13;
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
// 开启一个轮寻
JobScheduler jobScheduler = (JobScheduler) getSystemService(Context.JOB_SCHEDULER_SERVICE);
JobInfo.Builder jobBuilder = new JobInfo.Builder(jobId,new ComponentName(this,JobWakeUpService2.class));
//设置每两秒钟一次
jobBuilder.setPeriodic(2000);
jobScheduler.schedule(jobBuilder.build());
ArLog.i("TAG", "start JobWakeUpService2");
return START_STICKY;
}
@Override
public boolean onStartJob(JobParameters jobParameters) {
// 开启定时任务，定时轮寻 ， 看MessageService有没有被杀死
// 如果杀死了启动 轮寻onStartJob
// 判断服务有没有在运行
boolean messageServiceAlive = serviceAlive(GuardService2.class.getName());
if(!messageServiceAlive){
ArLog.i("TAG", "GuardService2 is killed ，restart it");
startService(new Intent(this,GuardService1.class));
}
boolean JobWakeUpService1Alive = serviceAlive(JobWakeUpService1.class.getName());
if(!JobWakeUpService1Alive){
ArLog.i("TAG", "JobWakeUpService1 is killed ，restart it");
startService(new Intent(this,JobWakeUpService1.class));
}
return false;
}
@Override
public boolean onStopJob(JobParameters jobParameters) {
return false;
}
/**
* 判断某个服务是否正在运行的方法
* @param serviceName
* 是包名+服务的类名（例如：net.loonggg.testbackstage.TestService）
* @return true代表正在运行，false代表服务没有正在运行
*/
private boolean serviceAlive(String serviceName) {
boolean isWork = false;
ActivityManager myAM = (ActivityManager)getSystemService(Context.ACTIVITY_SERVICE);
List myList = myAM.getRunningServices(100);
if (myList.size() <= 0) {
return false;
}
for (int i = 0; i < myList.size(); i++) {
String mName = myList.get(i).service.getClassName().toString();
if (mName.equals(serviceName)) {
isWork = true;
break;
}
}
return isWork;
}
}
DaemonActivity
public class DaemonActivity extends AppCompatActivity {
private static final java.lang.String TAG = "DaemonActivity";
private static DaemonActivity context;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.context = this;
Window window = getWindow();
window.setGravity(Gravity.LEFT & Gravity.TOP);
WindowManager.LayoutParams attributes = window.getAttributes();
attributes.x = 0;
attributes.y = 0;
attributes.width = 1;
attributes.height = 1;
window.setAttributes(attributes);
}
/**
* 监听手机的锁屏和开屏广播，锁屏后调用start开启这个activity
* 调用此方法时，activity未启动，不能使用this.context,只能用application的
*/
public static void startDaemon(){
Intent intent = new Intent(SightPlusApplication.getContext(),DaemonActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
SightPlusApplication.getContext().startActivity(intent);
ArLog.i(TAG,"startDaemon");
}
/**
* 监听手机的锁屏和开屏广播，开屏后调用stop销毁这个activity
* 调用此方法时，可以使用activity的context
*/
public static void stopDaemon(){
if (context != null){
ArLog.i(TAG,"stopDaemon");
context.finish();
}
}
}
AndroidManifest配置
增加一个管理类GuardAppManager一键启动和关闭
public class GuardAppManager {
private GuardAppManager(){}
private static volatile GuardAppManager mInstance;
private BootCompleteReceiver mReceiver;
public static GuardAppManager getInstance(){
if (mInstance == null){
synchronized (GuardAppManager.class){
if (mInstance == null){
return new GuardAppManager();
}
}
}
return mInstance;
}
public class BootCompleteReceiver extends BroadcastReceiver {
@Override public void onReceive(Context context, Intent intent) {
if(intent.getAction().equals(Intent.ACTION_SCREEN_OFF)) {
ArLog.i("TAG","ACTION_SCREEN_OFF");
DaemonActivity.startDaemon();
}
else if(intent.getAction().equals(Intent.ACTION_SCREEN_ON)){
ArLog.i("TAG","ACTION_SCREEN_ON");
DaemonActivity.stopDaemon();
}
}
}
/**
* 开启守护
* @param context
*/
public void start(Context context){
context.startService(new Intent(context, GuardService1.class));
context.startService(new Intent(context, GuardService2.class));
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP){
//必须大于5.0
context.startService(new Intent(context,JobWakeUpService2.class));
context.startService(new Intent(context,JobWakeUpService1.class));
}
IntentFilter filter = new IntentFilter();
filter.addAction(Intent.ACTION_SCREEN_ON);
filter.addAction(Intent.ACTION_SCREEN_OFF);
mReceiver = new BootCompleteReceiver();
context.registerReceiver(mReceiver,filter);
}
/**
* 关闭守护
* @param context
*/
public void stop(Context context){
if (mReceiver != null){
context.unregisterReceiver(mReceiver);
}
}
}
开启守护
GuardAppManager.getInstance().start(this);
关闭守护
GuardAppManager.getInstance().stop(this);