android4.0网络服务状态或者信号量强度上报过程（RIL Framework Java 部分）

网络服务状态或者网络信号量是通过Modem 主动上报信息来实现的，相关类有ServiceState,GsmServiceStateTracker,GSMPhone,TelephonyRegistry等。

1.比如现在所处的网络发生变化,RILReciver 收到上报信息，处理 RIL_UNSOL_RESPONSE_VOICE_NETWORK_STATE_CHANGED 信息。

case RIL_UNSOL_RESPONSE_VOICE_NETWORK_STATE_CHANGED:

if (RILJ_LOGD) unsljLog(response);

mVoiceNetworkStateRegistrants

.notifyRegistrants(new AsyncResult(null, null, null));

break;

2.经分析 mVoiceNetworkStateRegistrants，是由 GsmServiceStateTracker 构造的。

public GsmServiceStateTracker(GSMPhone phone) {

...

cm.registerForVoiceNetworkStateChanged(this, EVENT_NETWORK_STATE_CHANGED, null);

...

}

3.消息交给 EVENT_NETWORK_STATE_CHANGED 处理。GsmServiceStateTracker 处理 EVENT_NETWORK_STATE_CHANGED 消息

case EVENT_NETWORK_STATE_CHANGED:

pollState();

break;

4.调用 pollState();

default:

// Issue all poll-related commands at once

// then count down the responses, which

// are allowed to arrive out-of-order

pollingContext[0]++;

cm.getOperator(

obtainMessage(

EVENT_POLL_STATE_OPERATOR, pollingContext));

pollingContext[0]++;

cm.getDataRegistrationState(

obtainMessage(

EVENT_POLL_STATE_GPRS, pollingContext));

pollingContext[0]++;

cm.getVoiceRegistrationState(

obtainMessage(

EVENT_POLL_STATE_REGISTRATION, pollingContext));

pollingContext[0]++;

cm.getNetworkSelectionMode(

obtainMessage(

EVENT_POLL_STATE_NETWORK_SELECTION_MODE, pollingContext));

5.再次向rild 发送消息，等待返回信息 ，信息返回后 GsmServiceStateTracker 处理 EVENT_POLL_STATE_OPERATOR，EVENT_POLL_STATE_GPRS，EVENT_POLL_STATE_REGISTRATION，EVENT_POLL_STATE_NETWORK_SELECTION_MODE

6. GsmServiceStateTracker最后调用 pollStateDone();

7.调用 phone.notifyServiceStateChanged(ss);

8.调用 phoneBase 的 notifyServiceStateChanged

protected void notifyServiceStateChangedP(ServiceState ss) {

AsyncResult ar = new AsyncResult(null, ss, null);

mServiceStateRegistrants.notifyRegistrants(ar);

mNotifier.notifyServiceState(this);

}

9.DefaultPhoneNotifier的 notifyServiceState(this);

10.public void notifyServiceState(Phone sender) {

ServiceState ss = sender.getServiceState();

if (ss == null) {

ss = new ServiceState();

ss.setStateOutOfService();

}

try {

mRegistry.notifyServiceState(ss);

} catch (RemoteException ex) {

// system process is dead

}

}

11. mRegistry 是 TelephonyRegistry.

12.调用 TelephonyRegistry的 notifyServiceState

public void notifyServiceState(ServiceState state) {

if (!checkNotifyPermission("notifyServiceState()")){

return;

}

synchronized (mRecords) {

mServiceState = state;

for (Record r : mRecords) {

if ((r.events & PhoneStateListener.LISTEN_SERVICE_STATE) != 0) {

try {

r.callback.onServiceStateChanged(new ServiceState(state));

} catch (RemoteException ex) {

mRemoveList.add(r.binder);

}

}

}

handleRemoveListLocked();

}

broadcastServiceStateChanged(state);

}

13.回调应用程序的 onServiceStateChanged方法 ，可能会有多个应用程序，现在选择状态栏的处理程序，NetworkController处理网络变化。

public void onServiceStateChanged(ServiceState state) {

if (DEBUG) {

Slog.d(TAG, "onServiceStateChanged state=" + state);

}

mServiceState = state;

if (SystemProperties.getBoolean("ro.config.combined_signal", true)) {

/*

* if combined_signal is set to true only then consider data

* service state for signal display

*/

mDataServiceState = mServiceState.getDataState();

if (DEBUG) {

Slog.d(TAG, "Combining data service state" + mDataServiceState + "for signal");

}

}

updateTelephonySignalStrength();

updateDataNetType();

updateDataIcon();

refreshViews();

}

14. 信号量强度的传递也是类似，都需要状态栏应用(SystemUI)去更新数据。