之前在《MTK IMS框架简析（1）——代码架构及模块初始化》 中已经分析了ims代码的构成和重点类的初始化，接下来以启用VOLTE子功能为例，具体分析AP侧IMS服务的注册过程。
概要
IMS注册前提是系统启用了volte或wifi calling等功能，Volte开关一般在网络设置界面会提供（如下图），用户切换开关状态将触发ims的注册或注销。
启用Volte后的消息传递序列（这里时序图避免复杂化，只表现消息的正向传递，忽略消息的返回）
frameworkframeworkims appims apprild imsrild imsvolte_imsmvolte_imsmrildrildTurn on IMS feature打开IMS子功能RIL_REQUEST_SET_VOLTE_ENABLERIL_REQUEST_SET_IMS_VOICE_ENABLERIL_REQUEST_SET_IMS_ENABLERIL_UNSOL_IMS_ENABLE_STARTIMS_SERVICE_UPMSG_ID_IMS_ENABLE_INDMSG_ID_WRAP_IMSM_IMSPA_PDN_ACT_REQRequest Network建立IMS承载SETUP_DATA_CALL(ims apn)MSG_ID_WRAP_IMSPA_IMSM_PDN_ACT_ACK_RESP成功建立承载RIL_UNSOL_IMS_REGISTRATION_INFO上报IMS注册状态
整个过程大致分为3步：
1. 设置并启用ims
2. 建立ims承载
3. 注册ims服务
接下来结合代码详细分析。
IMS注册过程
从界面启用ims
此过程会向rild-ims下发3个消息，通知rild需要打开哪些ims业务，然后开启ims服务：
//启用volte语音服务
RIL_REQUEST_SET_VOLTE_ENABLE
RIL_REQUEST_SET_IMS_VOICE_ENABLE
//启动ims功能
RIL_REQUEST_SET_IMS_ENABLE这里就从用户打开界面开关开始分析。
ImsManager::setAdvanced4GMode方法为volte功能的开关，设置界面即通过此接口实现volte开关。
1. 向ImsConfig设置了feature(ImsConfig::setFeatureValue)
2. 打开ims (turnOnIms)。
//ImsManager.java
private void setAdvanced4GMode(boolean turnOn) throws ImsException {
checkAndThrowExceptionIfServiceUnavailable();
try {
ImsConfig config = getConfigInterface();
if (config != null) {
//设置启用volte语音
config.setFeatureValue(ImsConfig.FeatureConstants.FEATURE_TYPE_VOICE_OVER_LTE,
TelephonyManager.NETWORK_TYPE_LTE, turnOn ? 1 : 0, null);
}
} catch (ImsException e) {
}
//启用ims服务
if (turnOn) {
turnOnIms();
} else if (isImsTurnOffAllowed()) {
turnOffIms();
}
}ImsConfig::setFeatureValue 作用是告诉ril目前要启用ims的哪些功能.
当前讨论的例子是打开volte，因此参数为”FEATURE_TYPE_VOICE_OVER_LTE”。
其他业务的定义在ImsConfig.java中：
//ImsConfig.java
public static class FeatureConstants {
public static final int FEATURE_TYPE_UNKNOWN = -1;
/**
* FEATURE_TYPE_VOLTE supports features defined in 3GPP and
* GSMA IR.92 over LTE.
*/
public static final int FEATURE_TYPE_VOICE_OVER_LTE = 0;
/**
* FEATURE_TYPE_LVC supports features defined in 3GPP and
* GSMA IR.94 over LTE.
*/
public static final int FEATURE_TYPE_VIDEO_OVER_LTE = 1;
/**
* FEATURE_TYPE_VOICE_OVER_WIFI supports features defined in 3GPP and
* GSMA IR.92 over WiFi.
*/
public static final int FEATURE_TYPE_VOICE_OVER_WIFI = 2;
/**
* FEATURE_TYPE_VIDEO_OVER_WIFI supports features defined in 3GPP and
* GSMA IR.94 over WiFi.
*/
public static final int FEATURE_TYPE_VIDEO_OVER_WIFI = 3;
}ImsConfig实际上是ims app/ImsConfigImpl的代理，setFeatureValue方法具体逻辑在ImsConfigImpl中。
这里传入的feature为FEATURE_TYPE_VOICE_OVER_LTE，因此会向rild-ims下发2个消息：RIL_REQUEST_SET_VOLTE_ENABLE及RIL_REQUEST_SET_IMS_VOICE_ENABLE。
//ImsConfigImpl.java
public void setFeatureValue(int feature, int network, int value, ImsConfigListener listener) {
try {
try {
//将设置值保存到数据库
mStorage.setFeatureValue(feature, network, value);
//不同的feature需要不同的设置，这里只分析volte的处理
switch(feature) {
case ImsConfig.FeatureConstants.FEATURE_TYPE_VIDEO_OVER_LTE:
case ImsConfig.FeatureConstants.FEATURE_TYPE_VIDEO_OVER_WIFI:
...
break;
case ImsConfig.FeatureConstants.FEATURE_TYPE_VOICE_OVER_WIFI:
...
break;
case ImsConfig.FeatureConstants.FEATURE_TYPE_VOICE_OVER_LTE:
int oldVoLTEValue = SystemProperties.getInt(PROPERTY_VOLTE_ENALBE, 0);
int wfcEnable = SystemProperties.getInt(PROPERTY_WFC_ENALBE, 0);
if (value != oldVoLTEValue) {
//打开
if (value == ImsConfig.FeatureValueConstants.ON) {
//设置property
SystemProperties.set(PROPERTY_VOLTE_ENALBE,"1");
//向rild-ims下发RIL_REQUEST_SET_VOLTE_ENABLE
mRilAdapter.turnOnVolte(null);
if (wfcEnable == 0){
//向rild-ims下发RIL_REQUEST_SET_IMS_VOICE_ENABLE
mRilAdapter.turnOnImsVoice(null);
}
} else {//关闭
SystemProperties.set(PROPERTY_VOLTE_ENALBE,"0");
mRilAdapter.turnOffVolte(null);
if (wfcEnable == 0){
mRilAdapter.turnOffImsVoice(null);
}
}
}
break;
default:
break;
}
...
} catch (ImsException e) {
...
}
} catch (RemoteException e) {
throw new RuntimeException(e);
}
}ImsConfig处理完成，继续执行ImsManager::turnOnIms，这同样是aidl调用，实际操作由ImsService.turnOnIms执行。
//ImsManager.java
private void turnOnIms() throws ImsException {
checkAndThrowExceptionIfServiceUnavailable();
try {
mImsService.turnOnIms(mPhoneId);
} catch (RemoteException e) {
throw new ImsException("turnOnIms() ", e, ImsReasonInfo.CODE_LOCAL_IMS_SERVICE_DOWN);
}
}turnOnIms同样是向rild-ims下发消息：RIL_REQUEST_SET_IMS_ENABLE。
//ImsService.java
@Override
public void turnOnIms(int phoneId) {
if (mActivePhoneId != phoneId) {
mActivePhoneId = phoneId;
}
if (mImsState != PhoneConstants.IMS_STATE_ENABLE) {
mImsRILAdapter.turnOnIms(mHandler.obtainMessage(EVENT_SET_IMS_ENABLED_DONE));
mImsState = PhoneConstants.IMS_STATE_ENABLING;
} else {
}
}下发了这3条消息后，等待ImsRilAdapter上报RIL_UNSOL_IMS_ENABLE_START来确认IMS服务已经启用。
ImsService在构造方法中注册了RIL_UNSOL_IMS_ENABLE_START消息的监听，消息上报后便会由它处理。
//ImsService.java
mImsRILAdapter.registerForImsEnableStart(mHandler, EVENT_IMS_ENABLING_URC, null);- ImsService中对RIL_UNSOL_IMS_ENABLE_START的处理如下：
1. 发送ACTION_IMS_SERVICE_UP广播；
2. 调用enableImsAdapter()
//ImsService.java
case EVENT_IMS_ENABLING_URC:
//+EIMS: 1
if (mActivePhoneId != phoneId) {
mActivePhoneId = phoneId;
}
// notify AP Ims Service is up
intent = new Intent(ImsManager.ACTION_IMS_SERVICE_UP);
intent.putExtra(ImsManager.EXTRA_PHONE_ID, mActivePhoneId);
mContext.sendBroadcast(intent);
// enable ImsAdapter
enableImsAdapter();
mImsState = PhoneConstants.IMS_STATE_ENABLE;
break;在《MTK IMS框架简析（1）——代码架构及模块初始化》 中提到过，ACTION_IMS_SERVICE_UP会触发ImsPhone和相关telephony类的初始化，因此这里跳过。
而ImsAdatper的流程涉及到建立ims承载，在第二节中继续分析。
以流程图小结这部分：
建立IMS PDN连接
在ims注册之前，需要建立专用的数据连接。连接的建立由volte_imsm.so来触发，与普通数据连接一样，通过ConnectivityManager请求网络，并由telephony发起SETUP_DATA_CALL。
先了解下volte_imsm.so的作用。根据readme文件的描述，volte_imsm.so库用于建立承载，P-CSCF，鉴权等过程，MTK并没有开源：
#README
IMS relay module, handling NAS bearer, P-CSCF address discovery, IMS AKA and relay message among IMCB/IMSA/MAL modules
WHAT IT DOES?
=============
handle the request from IMCB/IMSA/MAL module
Send the event to IMCB/IMSA/MAL module, and receive the Responseims app负责与volte_imsm.so对接，一张图来表示相关的工作过程。
VaSocketIO运作在线程中，负责维护socket和输入输出，循环从socket中读取消息交由ImsEventDispatcher。
ImsEventDispatcher根据消息的类型分发给对应的VaEventDispatcher处理。
实现了VaEventDispatcher的类共有4个，分别负责：通话，数据，补充业务还有Timer（具体作用尚需研究）。
ImsAdapter负责控制功能的总开关。
大概清楚这块流程后，下面接着第一节的思路，继续分析ImsAdapter:enableImsAdapter()方法。
ImsAdapter.java
public void enableImsAdapter() {
synchronized (ImsEnabledThreadLock) {
if (!misImsAdapterEnabled) {
if (mIO.connectSocket() == true) {
//调用所有VaEventDispatcher的enableRequest方法
mImsEventDispatcher.enableRequest();
misImsAdapterEnabled = true;
synchronized (mIO.VaSocketIOThreadLock) {
mIO.VaSocketIOThreadLock.notify();
}
//启用ims栈（向volte_imsm下发一条消息）
enableImsStack();
} else {
sendMessageDelayed(
obtainMessage(MSG_IMSA_RETRY_IMS_ENABLE),
IMSA_RETRY_SOCKET_TIME);
}
}
}
}DataDispatcher负责建立承载相关处理，直接看DataDispatcher.enableRequest()方法的处理：
注册DATA_CONNECTION_STATE_CHANGED和SIM_STATE_CHANGED的监听。监听这2个消息是为了维护ims的连接，响应Data和SIM卡的变动。
DataDispatcher.java
public void enableRequest() {
synchronized (mHandler) {
Arrays.fill(mSimStatus, false);
IntentFilter filter = new IntentFilter();
filter.addAction(TelephonyManager.ACTION_PRECISE_DATA_CONNECTION_STATE_CHANGED);
filter.addAction(TelephonyIntents.ACTION_SIM_STATE_CHANGED);
mContext.registerReceiver(mBroadcastReceiver, filter);
mIsEnable = true;
}
}返回到ImsAdapter继续看enableImsStack()方法。从方法的命名上看，作用是启用ims栈，
向volte_imsm发送MSG_ID_IMS_ENABLE_IND消息：
private void enableImsStack() {
// Send IMS Enable to IMSM
VaEvent event = new VaEvent(Util.getDefaultVoltePhoneId(), MSG_ID_IMS_ENABLE_IND);
mIO.writeEvent(event);
return;
}消息的定义如下：
int MSG_ID_IMS_ENABLE_IND = 900003; // MSG_ID_WRAP_IMSPA_IMSM_ENABLE_IND
int MSG_ID_IMS_DISABLE_IND = 900004; // MSG_ID_WRAP_IMSPA_IMSM_DISABLE_IND,- 1
- 2
从Log看，MSG_ID_WRAP_IMSPA_IMSM_ENABLE_IND消息的作用应该是初始化volte_imsm相关模块，VoLTE Stack/UA/REG等模块被初始化：
volte_imsm随后会上报MSG_ID_WRAP_IMSM_IMSPA_PDN_ACT_REQ，通知上层发起IMS PDN连接，消息由DataDispatcher处理。
消息分发到DataDispatcher::handleDefaultBearerActivationRequest方法：
将请求数据封装成TransactionParam，设置超时处理，最后调用requestNwRequest方法。这里能看到请求的apn类型是IMS。
DataDispatcher.java
private void handleDefaultBearerActivationRequest(VaEvent event) {
//apn type为IMS
String apnType = PhoneConstants.APN_TYPE_IMS;
int phoneId = event.getPhoneId();
//请求数据封装成TransactionParam
DataDispatcherUtil.PdnActivationInd actInd = mDataDispatcherUtil
.extractDefaultPdnActInd(event);
TransactionParam param = new TransactionParam(actInd.transactionId,
event.getRequestID(), phoneId, apnType);
...
putTransaction(param);
if (apnType == PhoneConstants.APN_TYPE_IMS) {
int subId = SubscriptionManager.getSubIdUsingPhoneId(phoneId);
if (mSimStatus[phoneId] || subId > 0) {
mSimStatus[phoneId] = true;
//判断是否有合法的ims apn
if (!isImsApnExists(phoneId)) {
rejectDefaultBearerDataConnActivation(param, FAILCAUSE_UNKNOWN, 500);
return;
}
//设置超时，如果超过10秒没有进入开始连接的状态即触发
mHandler.removeMessages(MSG_ON_NOTIFY_ACTIVE_DATA_TIMEOUT);
mHandler.sendMessageDelayed(mHandler.obtainMessage(
MSG_ON_NOTIFY_ACTIVE_DATA_TIMEOUT, param),
MAX_NETWORK_ACTIVE_TIMEOUT_MS);
} else {
return;
}
}
//发起IMS连接请求
if (requestNwRequest(apnType, phoneId) < 0) {
rejectDefaultBearerDataConnActivation(param, FAILCAUSE_UNKNOWN, 0);
}
}requestNwRequest方法实例化NetworkRequest并填充数据后，通过ConnectivityManager.requestNetwork发起连接请求。
private int requestNwRequest(String requestApnType, int phoneId) {
...
NetworkCallback nwCb = mDataNetworkRequests[pos].nwCb;
Builder builder = new NetworkRequest.Builder();
//IMS & EIMS
builder.addCapability(APN_CAP_LIST[pos]);
builder.addTransportType(NetworkCapabilities.TRANSPORT_CELLULAR);
//指定为当前subId
builder.setNetworkSpecifier(String.valueOf(subId));
mDataNetworkRequests[pos].nwRequest = builder.build();
NetworkRequest nwRequest = mDataNetworkRequests[pos].nwRequest;
releaseNwRequest(requestApnType);
synchronized (mAPNStatuses) {
ApnStatus apnStatus = mAPNStatuses.get(requestApnType);
apnStatus.mName = requestApnType;//IMS
apnStatus.mStatus = TelephonyManager.DATA_DISCONNECTED;
apnStatus.isSendReq = true;
apnStatus.ifaceName = "";
//发起request
getConnectivityManager().requestNetwork(nwRequest, nwCb,
ConnectivityManager.MAX_NETWORK_REQUEST_TIMEOUT_MS);
}
...
return nRet;
}
private static final int[] APN_CAP_LIST = new int[] {
NetworkCapabilities.NET_CAPABILITY_IMS,
NetworkCapabilities.NET_CAPABILITY_EIMS
};接下来SETUP_DATA_CALL的工作由ConnectivityService和telephony数据模块完成。返回成功后，检查手机的网络接口发现新建了一个Interface——ccmni4
root@x6:/ # ifconfig
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope: Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:46 errors:0 dropped:0 overruns:0 frame:0
TX packets:46 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:3992 TX bytes:3992
ccmni4 Link encap:Ethernet HWaddr 12:7A:92:06:07:BE
inet6 addr: 2409:8809:8590:da21:279:6506:7e0d:afdc/64 Scope: Global
inet6 addr: fe80::279:6506:7e0d:afdc/64 Scope: Link
UP RUNNING NOARP MTU:1410 Metric:1
RX packets:26 errors:0 dropped:0 overruns:0 frame:0
TX packets:29 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:17494 TX bytes:18434
ccmni4是mtk在底层指定的ims默认承载接口的名称，连接建立后DataDispatcher还需要检查这个Interface的名字是否正确，最后发送ACT消息通知volte_imsm连接已经建立
//DataDispatcher.java
private static final String IMS_INTERFACE_NAME = "ccmni4";
private void handleDefaultBearerActivationResponse(Network network, String type) {
TransactionParam deacTrans = findTransaction
(VaConstants.MSG_ID_WRAP_IMSM_IMSPA_PDN_DEACT_REQ, type);
synchronized (mAPNStatuses) {
ApnStatus apnStatus = mAPNStatuses.get(type);
if (deacTrans == null) {
apnStatus.mStatus = TelephonyManager.DATA_CONNECTED;
ConnectivityManager cm = (ConnectivityManager) mContext
.getSystemService(Context.CONNECTIVITY_SERVICE);
LinkProperties mLink = cm.getLinkProperties(network);
...
apnStatus.ifaceName = mLink.getInterfaceName();
//检查iface名字是否为"ccmni4"
if (IMS_INTERFACE_NAME.equals(apnStatus.ifaceName)
|| EMERGENCY_INTERFACE_NAME.equals(apnStatus.ifaceName)) {
//发送MSG_ID_WRAP_IMSM_IMSPA_PDN_ACT_REQ通知volte_imsm
responseDefaultBearerDataConnActivated(
findTransaction(VaConstants.MSG_ID_WRAP_IMSM_IMSPA_PDN_ACT_REQ, type),
network.netId, apnStatus.ifaceName);
}
...
}
...
}
}
这部分的代码量较多，理解了设计意图后其实结构和流程都比较简单，同样以流程图总结：
注册IMS服务
完成注册
IMS注册基于SIP，这部分由ims核心模块处理，需要分析协议和模块设计，这里先不作深入探讨。
注册成功后，返回200 OK。
rild_ims将注册状态及capability通过RIL_UNSOL_IMS_REGISTRATION_INFO消息上报： 
ImsService在构造方法中注册过对RIL_UNSOL_IMS_REGISTRATION_INFO的监听，因此处理方法就在ImsService的handler中能找到。
mImsRILAdapter.registerForImsRegistrationInfo(mHandler, EVENT_IMS_REGISTRATION_INFO, null);- 1
ImsService 处理：
从EVENT_IMS_REGISTRATION_INFO中读取到ims注册状态和Capability，并通知监听者。
//ImsService.java
//IMS所支持的capability
private static final int IMS_VOICE_OVER_LTE = 1;
private static final int IMS_RCS_OVER_LTE = 2;
private static final int IMS_SMS_OVER_LTE = 4;
private static final int IMS_VIDEO_OVER_LTE = 8;
private static final int IMS_VOICE_OVER_WIFI = 16;
public void handleMessage(Message msg) {
AsyncResult ar;
Intent intent;
int phoneId = getMainCapabilityPhoneId();
switch (msg.what) {
case EVENT_IMS_REGISTRATION_INFO:
ar = (AsyncResult) msg.obj;
//根据协议的规定，CIREGU返回消息的第一字段表示注册状态，第二个表示capability
/**
* According to 3GPP TS 27.007 +CIREGU format
*
* AsyncResult.result is an Object[]
* ((Object[])AsyncResult.result)[0] is integer type to indicate the IMS regiration status.
* 0: not registered
* 1: registered
* ((Object[])AsyncResult.result)[1] is numeric value in hexadecimal format to indicate the IMS capability.
* 1: RTP-based transfer of voice according to MMTEL (see 3GPP TS 24.173 [87])
* 2: RTP-based transfer of text according to MMTEL (see 3GPP TS 24.173 [87])
* 4: SMS using IMS functionality (see 3GPP TS 24.341[101])
* 8: RTP-based transfer of video according to MMTEL (see 3GPP TS 24.183 [87])
*
*/
//对比socketId是否当前的active phoneId
int socketId = ((int[]) ar.result)[2];
if (socketId != mActivePhoneId) {
break;
}
int newImsRegInfo = ServiceState.STATE_POWER_OFF;
//读取Ims的注册状态
if (((int[]) ar.result)[0] == 1) {
newImsRegInfo = ServiceState.STATE_IN_SERVICE;
} else {
newImsRegInfo = ServiceState.STATE_OUT_OF_SERVICE;
}
//读取当前支持的capability
int newImsExtInfo = ((int[]) ar.result)[1];
mImsRegInfo = newImsRegInfo;
//通知ims注册状态更新
notifyRegistrationStateChange(mImsRegInfo);
if ((mImsRegInfo == ServiceState.STATE_IN_SERVICE)) {
mImsExtInfo = newImsExtInfo;
} else {
mImsExtInfo = 0;
}
//通知ims capability更新
notifyRegistrationCapabilityChange(mImsExtInfo);
break;
...
}
...
} 从LOG来看，此次CIREGU指令返回的结果是“1,5”，按照定义，1表示已注册，5代表同时支持IMS_VOICE_OVER_LTE和IMS_SMS_OVER_LTE，即语音和短信业务。
AT< +CIREGU: 1,5- 1
注册状态的同步
ImsManager获得注册状态和capability后，回调ImsPhoneCallTracker中实例化的ImsConnectionStateListener，数据最终将传递到ImsPhone。
ImsPhone中有ServiceState实例来标记data和ims voice服务状态，并有布尔值mImsRegistered来标记ims注册情况。
//ImsManager.java
private class ImsRegistrationListenerProxy extends IImsRegistrationListener.Stub {
private int mServiceClass;
private ImsConnectionStateListener mListener;
public ImsRegistrationListenerProxy(int serviceClass,
ImsConnectionStateListener listener) {
mServiceClass = serviceClass;
mListener = listener;
}
...
@Override
public void registrationConnected() {
if (mListener != null) {
mListener.onImsConnected();
}
}
@Override
public void registrationProgressing() {
if (mListener != null) {
mListener.onImsProgressing();
}
}
@Override
public void registrationDisconnected(ImsReasonInfo imsReasonInfo) {
if (mListener != null) {
mListener.onImsDisconnected(imsReasonInfo);
}
}
@Override
public void registrationResumed() {
if (mListener != null) {
mListener.onImsResumed();
}
}
@Override
public void registrationSuspended() {
if (mListener != null) {
mListener.onImsSuspended();
}
}
@Override
public void registrationFeatureCapabilityChanged(int serviceClass,
int[] enabledFeatures, int[] disabledFeatures) {
if (mListener != null) {
mListener.onFeatureCapabilityChanged(serviceClass,
enabledFeatures, disabledFeatures);
}
}
}ImsPhoneCallTracker如何处理注册信息和capability的上报：
1. 注册状态同步到ImsPhone；
2. Capability同步到mImsFeatureEnabled数组中，标记可用的ims业务；
3. 最后发出ACTION_IMS_STATE_CHANGED广播。
ImsPhoneCallTracker.java
/**
* Listen to the IMS service state change
*
*/
private ImsConnectionStateListener mImsConnectionStateListener =
new ImsConnectionStateListener() {
@Override
public void onImsConnected() {
mPhone.setServiceState(ServiceState.STATE_IN_SERVICE);
mPhone.setImsRegistered(true);
}
@Override
public void onImsDisconnected(ImsReasonInfo imsReasonInfo) {
mPhone.setServiceState(ServiceState.STATE_OUT_OF_SERVICE);
mPhone.setImsRegistered(false);
mPhone.processDisconnectReason(imsReasonInfo);
if (imsReasonInfo != null && imsReasonInfo.getExtraMessage() != null
&& !imsReasonInfo.getExtraMessage().equals("")) {
mImsRegistrationErrorCode = Integer.parseInt(imsReasonInfo.getExtraMessage());
}
}
@Override
public void onImsProgressing() {
}
@Override
public void onImsResumed() {
mPhone.setServiceState(ServiceState.STATE_IN_SERVICE);
}
@Override
public void onImsSuspended() {
mPhone.setServiceState(ServiceState.STATE_OUT_OF_SERVICE);
}
@Override
public void onFeatureCapabilityChanged(int serviceClass,
int[] enabledFeatures, int[] disabledFeatures) {
if (serviceClass == ImsServiceClass.MMTEL) {
boolean tmpIsVideoCallEnabled = isVideoCallEnabled();
// Check enabledFeatures to determine capabilities. We ignore disabledFeatures.
for (int i = ImsConfig.FeatureConstants.FEATURE_TYPE_VOICE_OVER_LTE;
i <= ImsConfig.FeatureConstants.FEATURE_TYPE_VIDEO_OVER_WIFI; i++) {
if (enabledFeatures[i] == i) {
mImsFeatureEnabled[i] = true;
} else if (enabledFeatures[i]
== ImsConfig.FeatureConstants.FEATURE_TYPE_UNKNOWN) {
mImsFeatureEnabled[i] = false;
} else {
}
}
if (tmpIsVideoCallEnabled != isVideoCallEnabled()) {
mPhone.notifyForVideoCapabilityChanged(isVideoCallEnabled());
}
for (ImsPhoneConnection connection : mConnections) {
connection.updateWifiState();
}
mPhone.onFeatureCapabilityChanged();
broadcastImsStatusChange();
}
}
};ImsPhone更新ServiceState的Log：
06-02 16:47:44.925 D/ImsPhone( 2170): updateDataServiceState:
defSs = 0 0 voice home data home 中国移动 中国移动 46000 中国移动 中国移动 46000 LTE LTE_CA CSS not supported 0 0 RoamInd=-1 DefRoamInd=-1 EmergOnly=false Ril Voice Regist state: 1 Ril Data Regist state: 1 mProprietaryDataRadioTechnology: 0 VoiceRejectCause: 0 DataRejectCause: -1 IsDataRoamingFromRegistration=false
//imsServiceState
imsSs = 0 0 voice home data home null null null null null null Unknown LTE_CA CSS not supported -1 -1 RoamInd=-1 DefRoamInd=-1 EmergOnly=false Ril Voice Regist state: 0 Ril Data Regist state: 0 mProprietaryDataRadioTechnology: 0 VoiceRejectCause: -1 DataRejectCause: -1 IsDataRoamingFromRegistration=false小结
以上分析只分析了AP侧流程，相对于完整的ims注册过程来说并不完整，核心部分的协议及信令流程许多对上层来说是透明的，需要对这些部分深入了解后再做补充。
原文地址:https://blog.csdn.net/wilschan0201/article/details/72846897