0.写在最前
当我们在activity调用startService启动一个service，同时在AndroidManifest中指定process时，将会开启一个新的进程，并在这个进程运行这个Service。
1.ContextImpl.startService()
@Override
public ComponentName startService(Intent service) {
warnIfCallingFromSystemProcess();
return startServiceCommon(service, false, mUser);
}
private ComponentName startServiceCommon(Intent service, boolean requireForeground,
UserHandle user) {
try {
validateServiceIntent(service);
service.prepareToLeaveProcess(this);
// ActivityManagerProxy,最终会调用ActivityManagerService
ComponentName cn = ActivityManager.getService().startService(
mMainThread.getApplicationThread(), service, service.resolveTypeIfNeeded(
getContentResolver()), requireForeground,
getOpPackageName(), user.getIdentifier());
if (cn != null) {
if (cn.getPackageName().equals("!")) {
throw new SecurityException(
"Not allowed to start service " + service
+ " without permission " + cn.getClassName());
} else if (cn.getPackageName().equals("!!")) {
throw new SecurityException(
"Unable to start service " + service
+ ": " + cn.getClassName());
} else if (cn.getPackageName().equals("?")) {
throw new IllegalStateException(
"Not allowed to start service " + service + ": " + cn.getClassName());
}
}
return cn;
} catch (RemoteException e) {
throw e.rethrowFromSystemServer();
}
}
2.AcvitityManagerService.startService()
@Override
public ComponentName startService(IApplicationThread caller, Intent service,
String resolvedType, boolean requireForeground, String callingPackage, int userId)
throws TransactionTooLargeException {
//获取调用方的pid和uid
final int callingPid = Binder.getCallingPid();
final int callingUid = Binder.getCallingUid();
final long origId = Binder.clearCallingIdentity();
ComponentName res;
try {
res = mServices.startServiceLocked(caller, service,
resolvedType, callingPid, callingUid,
requireForeground, callingPackage, userId);
} finally {
Binder.restoreCallingIdentity(origId);
}
return res;
}
}
3.接下来的调用流程ActiveServices.startServiceLocked ->ActiveServices.startServiceInnerLocked ->ActiveServices.bringUpServiceLocked
private String bringUpServiceLocked(ServiceRecord r, int intentFlags, boolean execInFg,
boolean whileRestarting, boolean permissionsReviewRequired)
throws TransactionTooLargeException {
if (r.app != null && r.app.thread != null) {
sendServiceArgsLocked(r, execInFg, false);
return null;
}
...
...
final boolean isolated = (r.serviceInfo.flags&ServiceInfo.FLAG_ISOLATED_PROCESS) != 0;
final String procName = r.processName;
String hostingType = "service";
ProcessRecord app;
// 当在service的配置清单里设置 android:isolatedProcess="true"
// 将会开启新的进程执行
if (!isolated) {
app = mAm.getProcessRecordLocked(procName, r.appInfo.uid, false);
if (app != null && app.thread != null) {
try {
app.addPackage(r.appInfo.packageName, r.appInfo.versionCode, mAm.mProcessStats);
//如果service运行在主进程中则会走到这里
realStartServiceLocked(r, app, execInFg);
return null;
} catch (TransactionTooLargeException e) {
throw e;
} catch (RemoteException e) {
Slog.w(TAG, "Exception when starting service " + r.shortName, e);
}
}
}
if (app == null && !permissionsReviewRequired) {
//根据上述判断，此时app从ProcessRecord取值为空，说明当前系统并不此进程
//则会调用到ActivityManagerService.startProcessLocked()方法
//似曾相识，在上一章文章也分析过，调用此方法最终会开启一个新的进程，并做一系列的初始化操作
//最终会到ActivityThread.main()方法
if ((app=mAm.startProcessLocked(procName, r.appInfo, true, intentFlags,
hostingType, r.name, false, isolated, false)) == null) {
String msg = "Unable to launch app "
+ r.appInfo.packageName + "/"
+ r.appInfo.uid + " for service "
+ r.intent.getIntent() + ": process is bad";
Slog.w(TAG, msg);
bringDownServiceLocked(r);
return msg;
}
if (isolated) {
r.isolatedProc = app;
}
}
if (r.fgRequired) {
mAm.tempWhitelistUidLocked(r.appInfo.uid,
SERVICE_START_FOREGROUND_TIMEOUT, "fg-service-launch");
}
//加入到Pending队列中，当新的进程创建完毕后会继续在pending队里取出这个service
if (!mPendingServices.contains(r)) {
mPendingServices.add(r);
}
...
...
return null;
}
接上一章《Android启动流程》的分析,AMS与Zygote通信，fork出一个子进程，同时进行一系列的初始化操作后，最后会来到ActivityThread.main()方法
注意：startProcess之后会将当前service加入pending列表中，以便后续进程初始化完后再从中取出来进行一系列操作。
4 AcitivityThread.main
public static void main(String[] args) {
...
...
Process.setArgV0("<pre-initialized>");
//准备main looper
Looper.prepareMainLooper();
ActivityThread thread = new ActivityThread();
thread.attach(false);
if (sMainThreadHandler == null) {
sMainThreadHandler = thread.getHandler();
}
//开启消息循环
Looper.loop();
throw new RuntimeException("Main thread loop unexpectedly exited");
}
5.ActivityThead.attach()
private void attach(boolean system) {
sCurrentActivityThread = this;
mSystemThread = system;
//此时system=false，什么时候会是true？还记得上一篇分析说过吗，当system_server时，system为true
if (!system) {
ViewRootImpl.addFirstDrawHandler(new Runnable() {
@Override
public void run() {
ensureJitEnabled();
}
});
RuntimeInit.setApplicationObject(mAppThread.asBinder());
final IActivityManager mgr = ActivityManager.getService();
try {
mgr.attachApplication(mAppThread);
} catch (RemoteException ex) {
throw ex.rethrowFromSystemServer();
}
// Watch for getting close to heap limit.
BinderInternal.addGcWatcher(new Runnable() {
@Override public void run() {
if (!mSomeActivitiesChanged) {
return;
}
Runtime runtime = Runtime.getRuntime();
long dalvikMax = runtime.maxMemory();
long dalvikUsed = runtime.totalMemory() - runtime.freeMemory();
if (dalvikUsed > ((3*dalvikMax)/4)) {
if (DEBUG_MEMORY_TRIM) Slog.d(TAG, "Dalvik max=" + (dalvikMax/1024)
+ " total=" + (runtime.totalMemory()/1024)
+ " used=" + (dalvikUsed/1024));
mSomeActivitiesChanged = false;
try {
mgr.releaseSomeActivities(mAppThread);
} catch (RemoteException e) {
throw e.rethrowFromSystemServer();
}
}
}
});
} else {
// Don't set application object here -- if the system crashes,
// we can't display an alert, we just want to die die die.
android.ddm.DdmHandleAppName.setAppName("system_process",
UserHandle.myUserId());
try {
mInstrumentation = new Instrumentation();
ContextImpl context = ContextImpl.createAppContext(
this, getSystemContext().mPackageInfo);
mInitialApplication = context.mPackageInfo.makeApplication(true, null);
mInitialApplication.onCreate();
} catch (Exception e) {
throw new RuntimeException(
"Unable to instantiate Application():" + e.toString(), e);
}
}
...
...
进入非system的判断语句执行逻辑
//确保开启Jit
ViewRootImpl.addFirstDrawHandler(new Runnable() {
@Override
public void run() {
ensureJitEnabled();
}
});
//获取ActivityManagerService在本地进程代理对象proxy
//最终会调用ActivityManagerService.attachApplication()
final IActivityManager mgr = ActivityManager.getService();
try {
mgr.attachApplication(mAppThread);
} catch (RemoteException ex) {
throw ex.rethrowFromSystemServer();
}
mAppThread是个啥?
final ApplicationThread mAppThread = new ApplicationThread();
//继承自Binder
private class ApplicationThread extends IApplicationThread.Stub {
}
mApplicationThead可以被看做作ActivityThead在远程(ActivityManagerService)的代理对象
6 AMS.attachApplication
@Override
public final void attachApplication(IApplicationThread thread) {
synchronized (this) {
int callingPid = Binder.getCallingPid();
final long origId = Binder.clearCallingIdentity();
attachApplicationLocked(thread, callingPid);
Binder.restoreCallingIdentity(origId);
}
}
// Find the application record that is being attached... either via
// the pid if we are running in multiple processes, or just pull the
// next app record if we are emulating process with anonymous threads.
ProcessRecord app;
long startTime = SystemClock.uptimeMillis();
if (pid != MY_PID && pid >= 0) {
synchronized (mPidsSelfLocked) {
app = mPidsSelfLocked.get(pid);
}
} else {
app = null;
}
//此时
if (app == null) {
Slog.w(TAG, "No pending application record for pid " + pid
+ " (IApplicationThread " + thread + "); dropping process");
EventLog.writeEvent(EventLogTags.AM_DROP_PROCESS, pid);
if (pid > 0 && pid != MY_PID) {
killProcessQuiet(pid);
//TODO: killProcessGroup(app.info.uid, pid);
} else {
try {
thread.scheduleExit();
} catch (Exception e) {
// Ignore exceptions.
}
}
return false;
}
// If this application record is still attached to a previous
// process, clean it up now.
if (app.thread != null) {
handleAppDiedLocked(app, true, true);
}
// Tell the process all about itself.
if (DEBUG_ALL) Slog.v(
TAG, "Binding process pid " + pid + " to record " + app);
final String processName = app.processName;
try {
AppDeathRecipient adr = new AppDeathRecipient(
app, pid, thread);
thread.asBinder().linkToDeath(adr, 0);
app.deathRecipient = adr;
} catch (RemoteException e) {
app.resetPackageList(mProcessStats);
startProcessLocked(app, "link fail", processName);
return false;
}
EventLog.writeEvent(EventLogTags.AM_PROC_BOUND, app.userId, app.pid, app.processName);
app.makeActive(thread, mProcessStats);
app.curAdj = app.setAdj = app.verifiedAdj = ProcessList.INVALID_ADJ;
app.curSchedGroup = app.setSchedGroup = ProcessList.SCHED_GROUP_DEFAULT;
app.forcingToImportant = null;
updateProcessForegroundLocked(app, false, false);
app.hasShownUi = false;
app.debugging = false;
app.cached = false;
app.killedByAm = false;
app.killed = false;
mHandler.removeMessages(PROC_START_TIMEOUT_MSG, app);
boolean normalMode = mProcessesReady || isAllowedWhileBooting(app.info);
List<ProviderInfo> providers = normalMode ? generateApplicationProvidersLocked(app) : null;
//安装provider比Application初始化还要早
if (providers != null && checkAppInLaunchingProvidersLocked(app)) {
Message msg = mHandler.obtainMessage(CONTENT_PROVIDER_PUBLISH_TIMEOUT_MSG);
msg.obj = app;
mHandler.sendMessageDelayed(msg, CONTENT_PROVIDER_PUBLISH_TIMEOUT);
}
checkTime(startTime, "attachApplicationLocked: before bindApplication");
if (!normalMode) {
Slog.i(TAG, "Launching preboot mode app: " + app);
}
...
...
checkTime(startTime, "attachApplicationLocked: immediately before bindApplication");
mStackSupervisor.mActivityMetricsLogger.notifyBindApplication(app);
if (app.instr != null) {
thread.bindApplication(processName, appInfo, providers,
app.instr.mClass,
profilerInfo, app.instr.mArguments,
app.instr.mWatcher,
app.instr.mUiAutomationConnection, testMode,
mBinderTransactionTrackingEnabled, enableTrackAllocation,
isRestrictedBackupMode || !normalMode, app.persistent,
new Configuration(getGlobalConfiguration()), app.compat,
getCommonServicesLocked(app.isolated),
mCoreSettingsObserver.getCoreSettingsLocked(),
buildSerial);
} else {
thread.bindApplication(processName, appInfo, providers, null, profilerInfo,
null, null, null, testMode,
mBinderTransactionTrackingEnabled, enableTrackAllocation,
isRestrictedBackupMode || !normalMode, app.persistent,
new Configuration(getGlobalConfiguration()), app.compat,
getCommonServicesLocked(app.isolated),
mCoreSettingsObserver.getCoreSettingsLocked(),
buildSerial);
}
boolean badApp = false;
boolean didSomething = false;
// 针对Activity做一下事情
if (normalMode) {
try {
if (mStackSupervisor.attachApplicationLocked(app)) {
didSomething = true;
}
} catch (Exception e) {
Slog.wtf(TAG, "Exception thrown launching activities in " + app, e);
badApp = true;
}
}
//
if (!badApp) {
try {
didSomething |= mServices.attachApplicationLocked(app, processName);
checkTime(startTime, "attachApplicationLocked: after mServices.attachApplicationLocked");
} catch (Exception e) {
Slog.wtf(TAG, "Exception thrown starting services in " + app, e);
badApp = true;
}
}
// Check if a next-broadcast receiver is in this process...
if (!badApp && isPendingBroadcastProcessLocked(pid)) {
try {
didSomething |= sendPendingBroadcastsLocked(app);
checkTime(startTime, "attachApplicationLocked: after sendPendingBroadcastsLocked");
} catch (Exception e) {
// If the app died trying to launch the receiver we declare it 'bad'
Slog.wtf(TAG, "Exception thrown dispatching broadcasts in " + app, e);
badApp = true;
}
}
接着调用thead.bindApplication（）方法，而thread则是ApplicationThread，接下来又会回到用户进程
7 ApplicationThread.bindApplication()
public final void bindApplication(String processName, ApplicationInfo appInfo,
List<ProviderInfo> providers, ComponentName instrumentationName,
ProfilerInfo profilerInfo, Bundle instrumentationArgs,
IInstrumentationWatcher instrumentationWatcher,
IUiAutomationConnection instrumentationUiConnection, int debugMode,
boolean enableBinderTracking, boolean trackAllocation,
boolean isRestrictedBackupMode, boolean persistent, Configuration config,
CompatibilityInfo compatInfo, Map services, Bundle coreSettings,
String buildSerial) {
if (services != null) {
// Setup the service cache in the ServiceManager
ServiceManager.initServiceCache(services);
}
setCoreSettings(coreSettings);
AppBindData data = new AppBindData();
data.processName = processName;
data.appInfo = appInfo;
data.providers = providers;
data.instrumentationName = instrumentationName;
data.instrumentationArgs = instrumentationArgs;
data.instrumentationWatcher = instrumentationWatcher;
data.instrumentationUiAutomationConnection = instrumentationUiConnection;
data.debugMode = debugMode;
data.enableBinderTracking = enableBinderTracking;
data.trackAllocation = trackAllocation;
data.restrictedBackupMode = isRestrictedBackupMode;
data.persistent = persistent;
data.config = config;
data.compatInfo = compatInfo;
data.initProfilerInfo = profilerInfo;
data.buildSerial = buildSerial;
sendMessage(H.BIND_APPLICATION, data);
}
接着通过mH这个handler发送消息，最终调用ActivityThead.handleBindApplication()
8 ActivityThead.handleBindApplication()
//忽略掉初始化配置一堆东西
final InstrumentationInfo ii;
if (data.instrumentationName != null) {
try {
ii = new ApplicationPackageManager(null, getPackageManager())
.getInstrumentationInfo(data.instrumentationName, 0);
} catch (PackageManager.NameNotFoundException e) {
throw new RuntimeException(
"Unable to find instrumentation info for: " + data.instrumentationName);
}
mInstrumentationPackageName = ii.packageName;
mInstrumentationAppDir = ii.sourceDir;
mInstrumentationSplitAppDirs = ii.splitSourceDirs;
mInstrumentationLibDir = getInstrumentationLibrary(data.appInfo, ii);
mInstrumentedAppDir = data.info.getAppDir();
mInstrumentedSplitAppDirs = data.info.getSplitAppDirs();
mInstrumentedLibDir = data.info.getLibDir();
} else {
ii = null;
}
final ContextImpl appContext = ContextImpl.createAppContext(this, data.info);
updateLocaleListFromAppContext(appContext,
mResourcesManager.getConfiguration().getLocales());
if (!Process.isIsolated()) {
setupGraphicsSupport(appContext);
}
if (ii != null) {
final ApplicationInfo instrApp = new ApplicationInfo();
ii.copyTo(instrApp);
instrApp.initForUser(UserHandle.myUserId());
final LoadedApk pi = getPackageInfo(instrApp, data.compatInfo,
appContext.getClassLoader(), false, true, false);
final ContextImpl instrContext = ContextImpl.createAppContext(this, pi);
try {
final ClassLoader cl = instrContext.getClassLoader();
mInstrumentation = (Instrumentation)
cl.loadClass(data.instrumentationName.getClassName()).newInstance();
} catch (Exception e) {
throw new RuntimeException(
"Unable to instantiate instrumentation "
+ data.instrumentationName + ": " + e.toString(), e);
}
final ComponentName component = new ComponentName(ii.packageName, ii.name);
mInstrumentation.init(this, instrContext, appContext, component,
data.instrumentationWatcher, data.instrumentationUiAutomationConnection);
if (mProfiler.profileFile != null && !ii.handleProfiling
&& mProfiler.profileFd == null) {
mProfiler.handlingProfiling = true;
final File file = new File(mProfiler.profileFile);
file.getParentFile().mkdirs();
Debug.startMethodTracing(file.toString(), 8 * 1024 * 1024);
}
} else {
mInstrumentation = new Instrumentation();
}
if ((data.appInfo.flags&ApplicationInfo.FLAG_LARGE_HEAP) != 0) {
dalvik.system.VMRuntime.getRuntime().clearGrowthLimit();
} else {
// Small heap, clamp to the current growth limit and let the heap release
// pages after the growth limit to the non growth limit capacity. b/18387825
dalvik.system.VMRuntime.getRuntime().clampGrowthLimit();
}
Application app;
try {
//最终在Instrumentation类中通过反射实例化一个application，并调用application.onCreate() 生命周期函数
app = data.info.makeApplication(data.restrictedBackupMode, null);
mInitialApplication = app;
// don't bring up providers in restricted mode; they may depend on the
// app's custom Application class
if (!data.restrictedBackupMode) {
if (!ArrayUtils.isEmpty(data.providers)) {
installContentProviders(app, data.providers);
// For process that contains content providers, we want to
// ensure that the JIT is enabled "at some point".
mH.sendEmptyMessageDelayed(H.ENABLE_JIT, 10*1000);
}
}
// Do this after providers, since instrumentation tests generally start their
// test thread at this point, and we don't want that racing.
try {
mInstrumentation.onCreate(data.instrumentationArgs);
}
catch (Exception e) {
throw new RuntimeException(
"Exception thrown in onCreate() of "
+ data.instrumentationName + ": " + e.toString(), e);
}
try {
mInstrumentation.callApplicationOnCreate(app);
} catch (Exception e) {
if (!mInstrumentation.onException(app, e)) {
throw new RuntimeException(
"Unable to create application " + app.getClass().getName()
+ ": " + e.toString(), e);
}
}
} finally {
...
}
// Preload fonts resources
FontsContract.setApplicationContextForResources(appContext);
try {
final ApplicationInfo info =
getPackageManager().getApplicationInfo(
data.appInfo.packageName,
PackageManager.GET_META_DATA /*flags*/,
UserHandle.myUserId());
if (info.metaData != null) {
final int preloadedFontsResource = info.metaData.getInt(
ApplicationInfo.METADATA_PRELOADED_FONTS, 0);
if (preloadedFontsResource != 0) {
data.info.getResources().preloadFonts(preloadedFontsResource);
}
}
} catch (RemoteException e) {
throw e.rethrowFromSystemServer();
}
}
1.Instrumentation最初这个类是为了测试用途，系统向开发者暴露一些app创建过程中的信息以便测试，后来发展成 hook这个类可以为插件化提供所有能力（动态分发activity，service。。。），谷歌当初也没想到还可以这样用。插件化的过程这里不细说，如果有时间将插件化的原理也整理一下
- Provider的安装要早于Application的实例化。
9 回到AMS.attachApplicationLocked()
if (app.instr != null) {
thread.bindApplication(processName, appInfo, providers,
app.instr.mClass,
profilerInfo, app.instr.mArguments,
app.instr.mWatcher,
app.instr.mUiAutomationConnection, testMode,
mBinderTransactionTrackingEnabled, enableTrackAllocation,
isRestrictedBackupMode || !normalMode, app.persistent,
new Configuration(getGlobalConfiguration()), app.compat,
getCommonServicesLocked(app.isolated),
mCoreSettingsObserver.getCoreSettingsLocked(),
buildSerial);
} else {
thread.bindApplication(processName, appInfo, providers, null, profilerInfo,
null, null, null, testMode,
mBinderTransactionTrackingEnabled, enableTrackAllocation,
isRestrictedBackupMode || !normalMode, app.persistent,
new Configuration(getGlobalConfiguration()), app.compat,
getCommonServicesLocked(app.isolated),
mCoreSettingsObserver.getCoreSettingsLocked(),
buildSerial);
}
....
....
//此时进程已经创建完，Application也已实例完
//然后再mServices的pending列表找出需要执行的service
if (!badApp) {
try {
didSomething |= mServices.attachApplicationLocked(app, processName);
checkTime(startTime, "attachApplicationLocked: after mServices.attachApplicationLocked");
} catch (Exception e) {
Slog.wtf(TAG, "Exception thrown starting services in " + app, e);
badApp = true;
}
}
10 ActiveServices.attachApplicationLocked
最终会调用realStartServiceLocked（）
private final void realStartServiceLocked(ServiceRecord r,
ProcessRecord app, boolean execInFg) throws RemoteException {
...
...
r.app = app;
r.restartTime = r.lastActivity = SystemClock.uptimeMillis();
final boolean newService = app.services.add(r);
//定时器
bumpServiceExecutingLocked(r, execInFg, "create");
mAm.updateLruProcessLocked(app, false, null);
updateServiceForegroundLocked(r.app, /* oomAdj= */ false);
mAm.updateOomAdjLocked();
boolean created = false;
try {
synchronized (r.stats.getBatteryStats()) {
r.stats.startLaunchedLocked();
}
mAm.notifyPackageUse(r.serviceInfo.packageName, PackageManager.NOTIFY_PACKAGE_USE_SERVICE);
app.forceProcessStateUpTo(ActivityManager.PROCESS_STATE_SERVICE);
//调用ApplicationThread的scheduleCreateService
app.thread.scheduleCreateService(r, r.serviceInfo,
mAm.compatibilityInfoForPackageLocked(r.serviceInfo.applicationInfo),
app.repProcState);
r.postNotification();
created = true;
} catch (DeadObjectException e) {
Slog.w(TAG, "Application dead when creating service " + r);
mAm.appDiedLocked(app);
throw e;
} finally {
if (!created) {
// Keep the executeNesting count accurate.
final boolean inDestroying = mDestroyingServices.contains(r);
serviceDoneExecutingLocked(r, inDestroying, inDestroying);
// Cleanup.
if (newService) {
app.services.remove(r);
r.app = null;
}
// Retry.
if (!inDestroying) {
scheduleServiceRestartLocked(r, false);
}
}
}
if (r.whitelistManager) {
app.whitelistManager = true;
}
//执行完onCreate执行，调用此方法bindService
requestServiceBindingsLocked(r, execInFg);
updateServiceClientActivitiesLocked(app, null, true);
// If the service is in the started state, and there are no
// pending arguments, then fake up one so its onStartCommand() will
// be called.
if (r.startRequested && r.callStart && r.pendingStarts.size() == 0) {
r.pendingStarts.add(new ServiceRecord.StartItem(r, false, r.makeNextStartId(),
null, null, 0));
}
//发送参数到client端，最终会导致onStartCommand触发
sendServiceArgsLocked(r, execInFg, true);
}
说明一下：
-
bumpServiceExecutingLocked将会开启一个定时器，
这也是Service.onCreate执行超过某个时间会触发ANR的由来，为什么说是某个时间呢？根据是否在前台进程执行service判断的，如果是在前台，则为20s，如果为后台，则为10*20s=200s -
app.thread.scheduleCreateService()最终会调用到service.onCreate()
-
requestServiceBindingsLocked(r, execInFg) 最终会调到bindService()，本章不作分析
4.sendServiceArgsLocked最终会调用到service.onStartCommand()
接下来继续分析scheduleCreateService，最终会调用ActivityThread.handleCreateService()
11 ActivityThread.handleCreateService()
private void handleCreateService(CreateServiceData data) {
....
Service service = null;
//反射实例化service
try {
java.lang.ClassLoader cl = packageInfo.getClassLoader();
service = (Service) cl.loadClass(data.info.name).newInstance();
} catch (Exception e) {
if (!mInstrumentation.onException(service, e)) {
throw new RuntimeException(
"Unable to instantiate service " + data.info.name
+ ": " + e.toString(), e);
}
}
try {
ContextImpl context = ContextImpl.createAppContext(this, packageInfo);
context.setOuterContext(service);
Application app = packageInfo.makeApplication(false, mInstrumentation);
service.attach(context, this, data.info.name, data.token, app,
ActivityManager.getService());
//调用service的生命周期函数
service.onCreate();
mServices.put(data.token, service);
try {
ActivityManager.getService().serviceDoneExecuting(
data.token, SERVICE_DONE_EXECUTING_ANON, 0, 0);
} catch (RemoteException e) {
throw e.rethrowFromSystemServer();
}
.....
}
12 ActivityThread.handleServiceArgs
过程10中最后执行sendServiceArgsLocked最终会到ActivityThread.handleServiceArgs
private void handleServiceArgs(ServiceArgsData data) {
Service s = mServices.get(data.token);
if (s != null) {
try {
if (data.args != null) {
data.args.setExtrasClassLoader(s.getClassLoader());
data.args.prepareToEnterProcess();
}
int res;
if (!data.taskRemoved) {
//回调service的onStartCommand的生命周期函数
res = s.onStartCommand(data.args, data.flags,data.startId);
...
//取消ANR定时器，并进行一些收尾工作，这里不作分析了
ActivityManager.getService().serviceDoneExecuting(
data.token, SERVICE_DONE_EXECUTING_START, data.startId, res)
}
}
AMS.serviceDoneExecuting()，会根据type，res修改ServiceRecord的某些值
11 不算总结的总结
至此，整个流程分析完，后续有空补个流程图吧，- -！
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