Andriod通话处理流程

一、总览
1、从java端发送at命令的处理流程。
2、unsolicited 消息从modem上报到java的流程。
3、猫相关的各种状态的监听和通知机制。
4、通话相关的图标变换的工作原理。
5、gprs拨号上网的通路原理。
6、通话相关的语音通路切换原理、震动接口。
7、通话相关的notification服务。
8、通话相关的各种server。

第一部分：从java端发送at命令的处理流程。
拨出电话流程：

1、contacts的androidmanifest.xml android:process="android.process.acore"说明此应用程序运行在acore进程中。
DialtactsActivity的intent-filter的action属性设置为main，catelog属性设置为 launcher，所以此activity能出现在主菜单中，并且是点击此应用程序的第一个界面。dialtactsactivity包含四个tab，分 别由TwelveKeyDialer,RecentCallsListActivity，两个activity-alias DialtactsContactsEntryActivity和DialtactsFavoritesEntryActivity分别
表示联系人和收藏tab，但是正真的联系人列表和收藏是由ContactsListActivity负责。

2、进入TwelveKeyDialer OnClick方法，按住的按钮id为： R.id.digits，执行
placecall()
Intent intent = new Intent(Intent.ACTION_CALL_PRIVILEGED,
Uri.fromParts("tel", number, null));
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);

3、intert.ACTION_CALL_PRIVILEGED实际字符串为android.intent.action.CALL_PRIVILEGED，通过查找知道了packegs/phone
下面的androidmanifest.xml中PrivilegedOutgoingCallBroadcaster activity-alias设置了intent-filter，所以需要找到其
targetactivity为OutgoingCallBroadcaster。所以进入OutgoingCallBroadcaster的
onCreate（）
//如果为紧急号码马上启动intent.setClass(this, InCallScreen.class); startActivity(intent);
Intent broadcastIntent = new Intent(Intent.ACTION_NEW_OUTGOING_CALL);
if (number != null) broadcastIntent.putExtra(Intent.EXTRA_PHONE_NUMBER, number);
broadcastIntent.putExtra(EXTRA_ALREADY_CALLED, callNow);
broadcastIntent.putExtra(EXTRA_ORIGINAL_URI, intent.getData().toString());
if (LOGV) Log.v(TAG, "Broadcasting intent " + broadcastIntent + ".");
sendOrderedBroadcast(broadcastIntent, PERMISSION, null, null,
Activity.RESULT_OK, number, null);

4、Intent.ACTION_NEW_OUTGOING_CALL实际字符串为android.intent.action.NEW_OUTGOING_CALL，通过查找知道了packegs/phone
下面的androidmanifest.xml中OutgoingCallReceiver Receiver接收此intent消息。找到OutgoingCallReceiver，执行
onReceive()函数
Intent newIntent = new Intent(Intent.ACTION_CALL, uri);
newIntent.putExtra(Intent.EXTRA_PHONE_NUMBER, number);
newIntent.setClass(context, InCallScreen.class);
newIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

5、请求拨号的java部分流程
onCreate(第一次)/onNewIntent(非第一次)
internalResolveIntent
placeCall(intent);
PhoneUtils.placeCall(mPhone, number, intent.getData());
phone.dial(number);
mCT.dial(newDialString);
dial(dialString, CommandsInterface.CLIR_DEFAULT);
cm.dial(pendingMO.address, clirMode, obtainCompleteMessage());//obtainCompleteMessage(EVENT_OPERATION_COMPLETE);
send(rr);
msg = mSender.obtainMessage(EVENT_SEND, rr);
acquireWakeLock();
msg.sendToTarget();
RILSender.handleMessage()
case EVENT_SEND:
...                   s.getOutputStream().write(dataLength);                  
s.getOutputStream().write(data);//从这里流程跑到下面ril.cpp中监听部份

6、请求拨号的c/c++部分流程
6.1、初始化事件循环，启动串口监听，注册socket监听。
rild.c->main()
(1)、RIL_startEventLoop
    //建立事件循环线程
    ret = pthread_create(&s_tid_dispatch, &attr, eventLoop, NULL);
    //注册进程唤醒事件回调
    ril_event_set (&s_wakeupfd_event, s_fdWakeupRead, true,
                processWakeupCallback, NULL);
    rilEventAddWakeup (&s_wakeupfd_event);
    //建立事件循环
    ril_event_loop
    for (;;) {
          ...
          n = select(nfds, &rfds, NULL, NULL, ptv);
          // Check for timeouts
          processTimeouts();
          // Check for read-ready
          processReadReadies(&rfds, n);
          // Fire away
          firePending();
        }
(2)、funcs = rilInit(&s_rilEnv, argc, rilArgv);//实际是通过动态加载动态库的方式执行reference-ril.c中的RIL_Init
     //单独启动一个线程读取串口数据
     ret = pthread_create(&s_tid_mainloop, &attr, mainLoop, NULL);
     fd = open (s_device_path, O_RDWR);
     ret = at_open(fd, onUnsolicited);
     ret = pthread_create(&s_tid_reader, &attr, readerLoop, &attr);
     RIL_requestTimedCallback(initializeCallback, NULL, &TIMEVAL_0);
     在initializeCallback中执行的程序：
     setRadioState (RADIO_STATE_OFF);
     at_handshake();
     /* note: we don't check errors here. Everything important will
     be handled in onATTimeout and onATReaderClosed */
     /*  atchannel is tolerant of echo but it must */
     /*  have verbose result codes */
     at_send_command("ATE0Q0V1", NULL);
     /*  No auto-answer */
     at_send_command("ATS0=0", NULL);
     ...
     //注册rild socket端口事件监听到事件循环中
(3)、RIL_register(funcs);
     s_fdListen = android_get_control_socket(SOCKET_NAME_RIL);
     ret = listen(s_fdListen, 4);
     ril_event_set (&s_listen_event, s_fdListen, false,
     listenCallback, NULL);//将此端口加入事件select队列
     rilEventAddWakeup (&s_listen_event);
     如果rild socket端口有数据来了将执行listencallback函数
     listencallback
     //为此客户端连接创建新的监听句柄，s_fdListen继续监听其他客户端的连接。
     s_fdCommand = accept(s_fdListen, (sockaddr *) &peeraddr, &socklen);
     ril_event_set (&s_commands_event, s_fdCommand, 1,
     processCommandsCallback, p_rs);//将此端口加入事件select队列
     rilEventAddWakeup (&s_commands_event);

6.2、socket监听，收到dial的socket请求
     processCommandsCallback
     //读数据到p_record中
     ret = record_stream_get_next(p_rs, &p_record, &recordlen);
     processCommandBuffer(p_record, recordlen);
     p.setData((uint8_t *) buffer, buflen);
     // status checked at end
     status = p.readInt32(&request);
     status = p.readInt32 (&token);//请求队列中的序号
     pRI = (RequestInfo *)calloc(1, sizeof(RequestInfo));
     pRI->token = token;
    /*
      包含#include "ril_commands.h"语句，结构体如下：
      typedef struct {
      int requestNumber;
      void (*dispatchFunction) (Parcel &p, struct RequestInfo *pRI);
      int(*responseFunction) (Parcel &p, void *response, size_t responselen);
      } CommandInfo;
    */
      pRI->pCI = &(s_commands[request]);
      pRI->p_next = s_pendingRequests;
      s_pendingRequests = pRI;
      pRI->pCI->dispatchFunction(p, pRI);
      //假设是接收了dial指令,pRI->PCI->dispatchFunction(p,pRI)，调用dispatchDial (p,pRI)
      dispatchDial (p,pRI)
      s_callbacks.onRequest(pRI->pCI->requestNumber, &dial, sizeof(dial), pRI);
      in reference-ril.c onRequest()
      ...
      switch (request) {
      case RIL_REQUEST_DIAL:
      requestDial(data, datalen, t);
      asprintf(&cmd, "ATD%s%s;", p_dial->address, clir);
      ret = at_send_command(cmd, NULL);
      err = at_send_command_full (command, NO_RESULT, NULL, NULL, 0, pp_outResponse);
      err = at_send_command_full_nolock(command, type, responsePrefix, smspdu,timeoutMsec, sponse);
      err = writeline (command);
//此处等待，直到收到成功应答或失败的应答,如：ok,connect,error cme等
      err = pthread_cond_wait(&s_commandcond, &s_commandmutex);
      waiting....
      waiting....
      /* success or failure is ignored by the upper layer here.it will call GET_CURRENT_CALLS and determine success that way */
      RIL_onRequestComplete(t, RIL_E_SUCCESS, NULL, 0);
      p.writeInt32 (RESPONSE_SOLICITED);
      p.writeInt32 (pRI->token);
      errorOffset = p.dataPosition();
      p.writeInt32 (e);
      if (e == RIL_E_SUCCESS) {
      /* process response on success */
      ret = pRI->pCI->responseFunction(p, response, responselen);
      if (ret != 0) {
         p.setDataPosition(errorOffset);
         p.writeInt32 (ret);
         }
      }
       sendResponse(p);
       sendResponseRaw(p.data(), p.dataSize());
       blockingWrite(fd, (void *)&header, sizeof(header));
       blockingWrite(fd, data, dataSize);

6.4、串口监听收到atd命令的应答"OK"或"no carrier"等
       readerLoop()
       line = readline();
       processLine(line);
       handleFinalResponse(line);
       pthread_cond_signal(&s_commandcond);//至此，前面的等待结束，接着执行RIL_onRequestComplete函数

6.5、java层收到应答后的处理,以dial为例子.
       ril.java->RILReceiver.run()
       for(;;)
       {
         ...
       length = readRilMessage(is, buffer);
       p = Parcel.obtain();
       p.unmarshall(buffer, 0, length);
       p.setDataPosition(0);
       processResponse(p);
       type = p.readInt();
       if (type == RESPONSE_SOLICITED) {
       processSolicited (p);
       serial = p.readInt();
       rr = findAndRemoveRequestFromList(serial);
       rr.mResult.sendToTarget();
       ......
       }
        CallTracker.java->handleMessage (Message msg)
       switch (msg.what) {
         case EVENT_OPERATION_COMPLETE:
         ar = (AsyncResult)msg.obj;
         operationComplete();
         cm.getCurrentCalls(lastRelevantPoll);
第二部分：unsolicited 消息从modem上报到java的流程。
  c++部份
         readerLoop()
         line = readline();
         processLine(line);
         handleUnsolicited(line);
         if (s_unsolHandler != NULL) {
         s_unsolHandler (line1, line2);//实际执行的是void onUnsolicited (const char *s, const char *sms_pdu)
         if (strStartsWith(s,"+CRING:")
         || strStartsWith(s,"RING")
         || strStartsWith(s,"NO CARRIER")
         || strStartsWith(s,"+CCWA")
          )
         RIL_onUnsolicitedResponse (RIL_UNSOL_RESPONSE_CALL_STATE_CHANGED, NULL, 0);
          p.writeInt32 (RESPONSE_UNSOLICITED);
          p.writeInt32 (unsolResponse);
          ret = s_unsolResponses[unsolResponseIndex].responseFunction(p, data, datalen);
          ret = sendResponse(p);
          sendResponseRaw(p.data(), p.dataSize());
          ret = blockingWrite(fd, (void *)&header, sizeof(header));
          blockingWrite(fd, data, dataSize);
  java部份
          ril.java->RILReceiver.run()
          for(;;)
          {
           ...
          length = readRilMessage(is, buffer);
          p = Parcel.obtain();
          p.unmarshall(buffer, 0, length);
          p.setDataPosition(0);
          processResponse(p);
          processUnsolicited (p);
          response = p.readInt();
          switch(response) {
          ...
          case RIL_UNSOL_RESPONSE_CALL_STATE_CHANGED: ret =  responseVoid(p); break;
          ...
          }
          switch(response) {
          case RIL_UNSOL_RESPONSE_CALL_STATE_CHANGED:
          if (RILJ_LOGD) unsljLog(response);
          mCallStateRegistrants
                    .notifyRegistrants(new AsyncResult(null, null, null));
          ...
          }

第三部分、第四部分：猫相关的各种状态的监听和通知机制／通话相关的图标变换的工作原理。
网络状态，edge,gprs图标的处理
a、注册监听部分
==>SystemServer.java
  init2()
    Thread thr = new ServerThread();
    thr.setName("android.server.ServerThread");
    thr.start();
      ServerThread.run()    com.android.server.status.StatusBarPolicy.installIcons(context, statusBar);
    sInstance = new StatusBarPolicy(context, service);
    // phone_signal
    mPhone = (TelephonyManager)context.getSystemService(Context.TELEPHONY_SERVICE);
    mPhoneData = IconData.makeIcon("phone_signal",
null, com.android.internal.R.drawable.stat_sys_signal_null, 0, 0);
    mPhoneIcon = service.addIcon(mPhoneData, null);
    // register for phone state notifications.
((TelephonyManager)mContext.getSystemService(Context.TELEPHONY_SERVICE)).listen(mPhoneStateListener,
    PhoneStateListener.LISTEN_SERVICE_STATE
  | PhoneStateListener.LISTEN_SIGNAL_STRENGTH
  | PhoneStateListener.LISTEN_CALL_STATE
  | PhoneStateListener.LISTEN_DATA_CONNECTION_STATE
  | PhoneStateListener.LISTEN_DATA_ACTIVITY);
  //实际是调用的是TelephonyRegistry.listen，此listen函数会将Iphonestatelistener添加到对应的的handler数组中，到时来了事件会轮询回调。
  // data_connection
  mDataData = IconData.makeIcon("data_connection", null, com.android.internal.R.drawable.stat_sys_data_connected_g, 0, 0);
  mDataIcon = service.addIcon(mDataData, null);
  service.setIconVisibility(mDataIcon, false);

b、事件通知部分
==>PhoneFactory.java
makeDefaultPhones()
  sPhoneNotifier = new DefaultPhoneNotifier();
  useNewRIL(context);
    phone = new GSMPhone(context, new RIL(context), sPhoneNotifier);
for example
==>DataConnectionTracker.java
notifyDefaultData(String reason)
    phone.notifyDataConnection(reason);
    mNotifier.notifyDataConnection(this, reason);
    ==>DefaultPhoneNotifier.java
    mRegistry = ITelephonyRegistry.Stub.asInterface(ServiceManager.getService(
                    "telephony.registry"));
mRegistry.notifyDataConnection(convertDataState(sender.getDataConnectionState()),
    sender.isDataConnectivityPossible(), reason, sender.getActiveApn(),
    sender.getInterfaceName(null));

第五部分：gprs拨号上网的通路原理。
上层java程序调用gprs流程：
=>PhoneApp.java
        onCreate()
        PhoneFactory.makeDefaultPhones(this);
        phone = new GSMPhone(context, new SimulatedCommands(), sPhoneNotifier);
        mDataConnection = new DataConnectionTracker (this);
        createAllPdpList();//建立缺省pdpconnection
        pdp = new PdpConnection(phone);
        dataLink = new PppLink(phone.mDataConnection);
        dataLink.setOnLinkChange(this, EVENT_LINK_STATE_CHANGED, null);
        //某个条件触发执行
        trySetupData(String reason)
        setupData(reason);
        pdp = findFreePdp();
        Message msg = obtainMessage();
        msg.what = EVENT_DATA_SETUP_COMPLETE;
        msg.obj = reason;
        pdp.connect(apn, msg);
        phone.mCM.setupDefaultPDP(apn.apn, apn.user, apn.password,
                            obtainMessage(EVENT_SETUP_PDP_DONE));
        //收到EVENT_SETUP_PDP_DONE消息
        =>pdpconnection.java
        handleMessage()
        case EVENT_SETUP_PDP_DONE:
        dataLink.connect();//dataLink是pppLink.java
        SystemService.start(SERVICE_PPPD_GPRS);//启动pppd_grps服务
        poll.what = EVENT_POLL_DATA_CONNECTION;
        sendMessageDelayed(poll, POLL_SYSFS_MILLIS);//启动轮询，看是否成功连接gprscheckPPP()//每隔5秒轮询，看是否连接成功，或断开
        //如果已经连接
        mLinkChangeRegistrant.notifyResult(LinkState.LINK_UP);
        //执行到pdpconnection.handleMessage()
        case EVENT_LINK_STATE_CHANGED
        onLinkStateChanged(ls);
        case LINK_UP:
        notifySuccess(onConnectCompleted);
        onCompleted.sendToTarget();
        //执行dataConnectionTracker.java的handleMessage()
        case EVENT_DATA_SETUP_COMPLETE
        notifyDefaultData(reason);
        setupDnsProperties();
        setState(State.CONNECTED);
        phone.notifyDataConnection(reason);
        startNetStatPoll();
        resetPollStats();
       1、读取发送出去的包数和接受到的包数
       2、如果发送的数据包且没有收到应答包数n大于等于看门狗追踪的限定包数。
       2.1、开始轮询pdp context list，尝试恢复网络连接
       2.2、如果轮询24次后还没有联通网络则停止网络状态轮询，进行一次ping实验。
       2.2.1、如果ping成功则，重新进行网络状态轮询，否则发送EVENT_START_RECOVERY事件。
        // reset reconnect timer
        nextReconnectDelay = RECONNECT_DELAY_INITIAL_MILLIS;
着重c++部分代码的角度分析
＝>DataConnectionTracker.java
        trySetupData(String reason)
        setupData(reason);
＝>PdpConnection.java
        pdp.connect(apn, msg);
=>RIL.JAVA
        phone.mCM.setupDefaultPDP(apn.apn, apn.user, apn.password,
        obtainMessage(EVENT_SETUP_PDP_DONE));
        send(rr);
        //send socket to RIL
        //enter c++ layer
=>ril.cpp
        processCommandsCallback (int fd, short flags, void *param)
        processCommandBuffer(p_record, recordlen);
        status = p.readInt32(&request);
        pRI->pCI = &(s_commands[request]);
        pRI->pCI->dispatchFunction(p, pRI);
        dispatchStrings();
        s_callbacks.onRequest(pRI->pCI->requestNumber, pStrings, datalen, pRI);
=>reference-ril.c
        onRequest();
        requestSetupDefaultPDP(data, datalen, t);
        err = write_at_to_data_channel("ATD*99***1#",1);
        //after a while.get "connect" from data channel,so need to send socket message to java layer.
        p.writeInt32 (RESPONSE_SOLICITED);
        p.writeInt32 (pRI->token);//the serial No  in the request list.
        errorOffset = p.dataPosition();
        p.writeInt32 (e);
        if (e == RIL_E_SUCCESS) {
        /* process response on success */
        ret = pRI->pCI->responseFunction(p, response, responselen);
        /* if an error occurred, rewind and mark it */
        if (ret != 0) {
        p.setDataPosition(errorOffset);
        p.writeInt32 (ret);
        }
        }
        sendResponse(p);
        sendResponseRaw(p.data(), p.dataSize());
        ret = blockingWrite(fd, (void *)&header, sizeof(header));
        blockingWrite(fd, data, dataSize);
=>RIL.JAVA
        RILReceiver.run();
        length = readRilMessage(is, buffer);
        p = Parcel.obtain();
        p.unmarshall(buffer, 0, length);
        p.setDataPosition(0);
        processResponse(p);
        processSolicited (p);
        serial = p.readInt();
        error = p.readInt();
        rr = findAndRemoveRequestFromList(serial);
        ret =  responseStrings(p);
        if (rr.mResult != null) {
        AsyncResult.forMessage(rr.mResult, ret, null);
                               rr.mResult.sendToTarget();
        }
=>pdpConnection.java
        handleMessage()
        case EVENT_SETUP_PDP_DONE:
        ...
        dataLink.connect();
=>pppLink.java
        SystemProperties.set(PROPERTY_PPPD_EXIT_CODE, "");
        SystemService.start(SERVICE_PPPD_GPRS);//启动pppd_grps服务
        poll.what = EVENT_POLL_DATA_CONNECTION;
        sendMessageDelayed(poll, POLL_SYSFS_MILLIS);
        dataConnection.state = State.CONNECTING;
        handleMessage()
        case EVENT_POLL_DATA_CONNECTION
        checkPPP();
        if (ArrayUtils.equals(mCheckPPPBuffer, UP_ASCII_STRING, UP_ASCII_STRING.length)
        || ArrayUtils.equals(mCheckPPPBuffer, UNKNOWN_ASCII_STRING,
    UNKNOWN_ASCII_STRING.length) && dataConnection.state == State.CONNECTING)
        if (mLinkChangeRegistrant != null) {
mLinkChangeRegistrant.notifyResult(LinkState.LINK_UP);
=>pdpConnection.java
        handleMessage()
        case EVENT_LINK_STATE_CHANGED:
        DataLink.LinkState ls  = (DataLink.LinkState) ar.result;
        onLinkStateChanged(ls);
        case LINK_UP:
        notifySuccess(onConnectCompleted);
        AsyncResult.forMessage(onCompleted);
        onCompleted.sendToTarget();             
=>DataConnectionTracker.java
        handleMessage()
        case EVENT_DATA_SETUP_COMPLETE:
        ...                   SystemProperties.set("gsm.defaultpdpcontext.active", "true");
        notifyDefaultData(reason);
        setupDnsProperties();//设置dns，gw，我们的实现方式是在pppd中设置的，不用pppd拨号的适用。
        setState(State.CONNECTED);
        phone.notifyDataConnection(reason);
        mNotifier.notifyDataConnection(this, reason);
＝>DefaultPhoneNotifier.java
        //mRegistry = ITelephonyRegistry.Stub.asInterface(ServiceManager.getService(
                    "telephony.registry"));构造函数中初始化了mRegistry                           mRegistry.notifyDataConnection(convertDataState(sender.getDataConnectionState()),                                       sender.isDataConnectivityPossible(), reason, sender.getActiveApn(),
sender.getInterfaceName(null));
startNetStatPoll();   
        }

第六部分：通话相关的语音通路切换原理、震动接口
6、语音通路
6.1、设置语音通路的路由
目前我们有两处处理:

a、CallTracker.java中的handlePollCalls（）检测到＋clcc返回的电话列表中有状态为DriverCall.State.ALERTING(表示拨打电话后，对方已经振铃)，此时需要设置语音通路为MODE_IN_CALL

b、PhoneUtils.java中setAudioMode（）函数

c、调用通路分析
AudioManager audioManager = (AudioManager) context.getSystemService
   (Context.AUDIO_SERVICE);
             audioManager.setMode(mode);
             AudioManager.setMode(mode);
             AudioService.setMode(mode);
             AudioSystem.setMode(mode);（native function)
android_media_AudioSystem.cpp==>android_media_AudioSystem_setMode()
             AudioSystem.cpp==>setMode()
             const sp& af = AudioSystem::get_audio_flinger();
             binder = sm->getService(String16("media.audio_flinger"));
             ...
             gAudioFlinger = interface_cast(binder);
             ...
             return gAudioFlinger;
通过查找“media.audio_flinger”发现AudioFlinger.cpp==> instantiate()//Main_mediaserver.cpp中被实例化。              defaultServiceManager()->addService(String16("media.audio_flinger"), new AudioFlinger());
          mAudioHardware = AudioHardwareInterface::create();
          LOGV("Creating Vendor Specific AudioHardware");
          hw = createAudioHardware();
          return new AudioHardwareMarvell();
          return af->setMode(mode);
          AudioHardwareLittle.cpp==>setMode(mode)
          doRouting();
          enable_incall_headphone()//or others...
          system("alsactl -f /etc/alsactl/asound.state_none restore");
          system("alsactl -f /etc/alsactl/asound.state_headset_r_s restore");

6.2、来电播放振铃,挂断或接听停止振铃。
          ==>Phone.app
          onCreate()
          ringer = new Ringer(phone);
          Vibrator mVibrator = new Vibrator();
          mService = IHardwareService.Stub.asInterface(ServiceManager.getService("hardware"));
          notifier = new CallNotifier(this, phone, ringer, mBtHandsfree);
          mPhone.registerForIncomingRing(this, PHONE_INCOMING_RING, null);
          mPhone.registerForPhoneStateChanged(this, PHONE_STATE_CHANGED, null);
          mPhone.registerForDisconnect(this, PHONE_DISCONNECT, null);
          ...
          case PHONE_INCOMING_RING:
          mRinger.ring();
          mHardwareService.setAttentionLight(true);
          mVibratorThread.start();
          while (mContinueVibrating) {
          mVibrator.vibrate(VIBRATE_LENGTH);
          SystemClock.sleep(VIBRATE_LENGTH + PAUSE_LENGTH);
            }
          ...
          makeLooper();
          mRingHandler.sendEmptyMessage(PLAY_RING_ONCE);
          ...
          case PLAY_RING_ONCE:
PhoneUtils.setAudioMode(mContext,AudioManager.MODE_RINGTONE);
          r.play();
          ...
          case PHONE_DISCONNECT:
          case PHONE_STATE_CHANGED:
          ...
          mRinger.stopRing();
          Message msg = mRingHandler.obtainMessage(STOP_RING);
          msg.obj = mRingtone;
          mRingHandler.sendMessage(msg);
          case STOP_RING:
             r.stop();
             getLooper().quit();
          ...mVibrator.cancel();

第七部分：通话相关的notification服务
7、通话相关的notification服务。
7.1、NotificationMgr
==>PhoneApp.java
onCreate()
NotificationMgr.init(this)//NotificationMgr.java//此类主要负责电话通知的具体表现（通知 和取消通知），未接图标、通话中、蓝牙激活中、保持中，静音、免提等。封装了简单的瞬间显示文本消息的功能。提供漫游数据连接禁止的通知封装和漫游数据连 接允许时取消通知
sMe = new NotificationMgr(context);
mNotificationMgr = (NotificationManager)
context.getSystemService(Context.NOTIFICATION_SERVICE);
mStatusBar = (StatusBarManager) context.getSystemService(Context.STATUS_BAR_SERVICE); //主要用于显示静音和speaker状态的图表（在状态条右边显示）
sMe.updateNotifications();//主要功能是：
1、查询是否有未读的未接听电话，并显示到状态栏图标，和通知列表
2、根据是否是电话状态，更新状态栏图表和通知列表（可能是激活，蓝牙，保持等）
7.2、CallNotifier
==>PhoneApp.java
onCreate()
notifier = new CallNotifier(this, phone, ringer, mBtHandsfree);//此类主要是监听通话相关的事件，然后进行例如来电播放铃声，震动。挂断、接听停止振铃等（调用Ringer类实现此功 能)，根据不同的状态调用调用NotificationMgr进行具体的通知和取消通知。
第八部分： 通话相关的各种server
电话通信相关的服务：
(1)、从ServiceManager得到的：
a、wifiService
b、PhoneInterfaceManager
c、PhoneSubInfo
d、SimPhoneBookInterfaceManager
e、SimSmsInterfaceManager
f、TelephonyRegistry
g、NetStatService
h、ConnectivityService

(2)、从ApplicationContext得到的：
a、TelephonyManager