Android8.1 开关VOLTE流程分析

前言

最近有需求需要实现插卡默认打开volte功能，顺带研究了下volte的流程，在此做个记录

开始

从settings设置界面入手，网络和互联网-->移动网络-->volte高清通话(电信卡)/增强型4g lte模式（移动卡）

找到网络和互联网加载对应的fragment为networkdashboardfragment，

源码位置 vendor\mediatek\proprietary\packages\apps\mtksettings\src\com\android\settings\network\networkdashboardfragment.java，

networkdashboardfragment加载的布局xml为 network_and_internet.xml

源码位置 vendor\mediatek\proprietary\packages\apps\mtksettings\res\xml\network_and_internet.xml

<preferencescreen
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:settings="http://schemas.android.com/apk/res/com.android.settings"
android:title="@string/network_dashboard_title">

...

<com.android.settingslib.restrictedpreference
    android:key="mobile_network_settings"
    android:title="@string/network_settings_title"
    android:summary="@string/summary_placeholder"
    android:icon="@drawable/ic_network_cell"
    android:dependency="toggle_airplane"
    android:order="-15"
    settings:keywords="@string/keywords_more_mobile_networks"
    settings:userrestriction="no_config_mobile_networks"
    settings:useadmindisabledsummary="true">
    <intent
        android:action="android.intent.action.main"
        android:targetpackage="com.android.phone"
        android:targetclass="com.android.phone.mobilenetworksettings"/>
</com.android.settingslib.restrictedpreference>

从上面可以看出移动网络对应的目标启动类为mobilenetworksettings

源码位置 vendor\mediatek\proprietary\packages\services\telephony\src\com\android\phone\mobilenetworksettings.java

代码不算多，2400多行，别被吓到了，只需找我们关心的即可

private void addenhanced4glteswitchpreference(preferencescreen preferencescreen) {
        int phoneid = subscriptionmanager.getphoneid(mphone.getsubid());
        log("[addenhanced4glteswitchpreference] volteenabled :"
                + isvolteenabled());
        if (mbutton4glte != null) {
            log("[addenhanced4glteswitchpreference] remove mbutton4glte!");
            //移除google原生的volte开关
            preferencescreen.removepreference(mbutton4glte);
        }
        //是否包含ct插件
        boolean isctplugin = extensionmanager.getmobilenetworksettingsext().isctplugin();
        log("[addenhanced4glteswitchpreference] ss :" + isctplugin);
        if (isvolteenabled() && !isctplugin) {
            int order = mbuttonenablednetworks.getorder() + 1;
            //实例化volte开关
            menhancedbutton4glte = new enhanced4glteswitchpreference(this, mphone.getsubid());
            /// still use google's key, title, and summary. 将原来的key依旧设置给新的volte开关，用于处理点击事件
            menhancedbutton4glte.setkey(button_4g_lte_key);
            /// m: [ct volte]
            // show "volte" for ct volte sim
            if (telephonyutilsex.isctvolteenabled()
                    && telephonyutilsex.isctsim(mphone.getsubid())) {
                menhancedbutton4glte.settitle(r.string.hd_voice_switch_title);//volte高清通话
                menhancedbutton4glte.setsummary(r.string.hd_voice_switch_summary);//启用前应先向运营商确认已开通此功能，否则可能影响正常通话
            } else {
                persistablebundle carrierconfig =
                phoneglobals.getinstance().getcarrierconfigforsubid(mphone.getsubid());
                boolean usevariant4gltetitle = carrierconfig.getboolean(
                        carrierconfigmanager.key_enhanced_4g_lte_title_variant_bool);
                int enhanced4gltemodetitleid = usevariant4gltetitle ?
                        r.string.enhanced_4g_lte_mode_title_variant :
                        r.string.enhanced_4g_lte_mode_title;//增强型 4g lte 模式
                menhancedbutton4glte.settitle(enhanced4gltemodetitleid);
            }
            /// m: [ct volte]
            // show "volte" for ct volte sim
            if (!telephonyutilsex.isctvolteenabled()
                    || !telephonyutilsex.isctsim(mphone.getsubid())) {
            /// @}
                menhancedbutton4glte.setsummary(r.string.enhanced_4g_lte_mode_summary);//使用 lte 服务改进语音和其他通信功能（推荐）
            }
            menhancedbutton4glte.setonpreferencechangelistener(this);
            menhancedbutton4glte.setorder(order);
            /// m: customize the lte switch preference. @{
            extensionmanager.getmobilenetworksettingsext()
                    .customizeenhanced4glteswitchpreference(this, menhancedbutton4glte);
            /// @}
        } else {
            menhancedbutton4glte = null;
        }
    }

开关的ui分析完了，我们接着看下volte开关的点击事件

    public boolean onpreferencechange(preference preference, object objvalue) {
        final int phonesubid = mphone.getsubid();
        if (onpreferencechangemtk(preference, objvalue)) {//新实例化的volte开关处理点击事件
            return true;
        }
        if (preference == mbuttonpreferrednetworkmode) {
        ....
        } else if (preference == mbutton4glte) {//google原生的volte点击事件
            switchpreference enhanced4gmodepref = (switchpreference) preference;
            boolean enhanced4gmode = !enhanced4gmodepref.ischecked();
            enhanced4gmodepref.setchecked(enhanced4gmode);
            log.e("networksettings", "enhanced4gmode="+enhanced4gmode + " phoneid="+mphone.getphoneid());
            mtkimsmanager.setenhanced4gltemodesetting(this, enhanced4gmodepref.ischecked(),
                    mphone.getphoneid());
        }

新实例化的volte开关处理点击事件

private boolean onpreferencechangemtk(preference preference, object objvalue) {
        string voltetitle = getresources().getstring(r.string.hd_voice_switch_title);
        string ltetitle = getresources().getstring(r.string.enhanced_4g_lte_mode_title);
        log("[onpreferencechangemtk] preference = " + preference.gettitle());

        if ((menhancedbutton4glte == preference) || preference.gettitle().equals(voltetitle)
                || preference.gettitle().equals(ltetitle)) {
            enhanced4glteswitchpreference ltepref = (enhanced4glteswitchpreference) preference;
            log("[onpreferencechangemtk] ischecked = " + ltepref.ischecked());
            /// m: [ct volte] @{
            if (telephonyutilsex.isctvolteenabled() && telephonyutilsex.isctsim(
                    mphone.getsubid())
                    && !ltepref.ischecked()) {
                int type = telephonymanager.getdefault().getnetworktype(mphone.getsubid());
                log("network type = " + type);
                if (telephonymanager.network_type_lte != type
                        && !telephonyutilsex.isroaming(mphone)
                        && (telephonyutilsex.getmainphoneid() == mphone.getphoneid()
                        || telephonyutilsex.isbothslotct4gsim(msubscriptionmanager))) {
                    if (!telephonyutilsex.isctautovolteenabled()) {
                        showvolteunavailabledialog();
                        return false;
                    }
                }
            }
            ltepref.setchecked(!ltepref.ischecked());
            log.e("networksettings", "ltepref.ischecked()="+ltepref.ischecked() + " phoneid="+mphone.getphoneid());
            mtkimsmanager.setenhanced4gltemodesetting(this, ltepref.ischecked(),
                    mphone.getphoneid());
            return true;
        }
        return false;
    }

这个函数处理如果点击的是新实例化的vlote开关，或者volte整个条目，其它返回false，由原来的onpreferencechange接着处理事件。

可以看到，最终通过mtkimsmanager.setenhanced4gltemodesetting(this, ltepref.ischecked(), mphone.getphoneid()); 来控制volte的打开和关闭。

继续跟进 源码位置 vendor\mediatek\proprietary\frameworks\opt\net\ims\src\java\com\mediatek\ims\internal\mtkimsmanager.java

public static void setenhanced4gltemodesetting(context context, boolean enabled, int phoneid) {
    int value = enabled ? 1 : 0;

    if (issupportmims() == false) {
        phoneid = getmainphoneidforsingleims(context);
        android.provider.settings.global.putint(
                context.getcontentresolver(),
                android.provider.settings.global.enhanced_4g_mode_enabled, value);

        if (isnonttyorttyonvolteenabled(context, phoneid)) {
            imsmanager imsmanager = imsmanager.getinstance(context, phoneid);
            if (imsmanager != null) {
                try {
                    imsmanager.setadvanced4gmode(enabled);
                } catch (imsexception ie) {
                    // do nothing
                }
            }
        }
    } else {
        simsmanagerext = getimsmanagerplugininstance(context);
        if (simsmanagerext != null) {
            phoneid = simsmanagerext.getimsphoneid(context, phoneid);
        }
        imsmanager imsmanager = imsmanager.getinstance(context, phoneid);
        if(imsmanager != null) {
            imsmanager.setenhanced4gltemodesettingforslot(enabled);
        } else {
            loge("setenhanced4gltemodesetting");
            loge("getinstance null for phoneid=" + phoneid);
        }
    }

}

这里需要关注下issupportmims()的返回结果

//private static final string multi_ims_support = "persist.mtk_mims_support";
public static boolean issupportmims() {
    return (systemproperties.getint(multi_ims_support, 1) > 1);
}

systemproperties读取的是build.prop中的值，经查找persist.mtk_mims_support不存在，则为默认值1, issupportmims()结果为false，

那么回到上面的逻辑中，走if代码块，将volte的状态保存到settings.global.enhanced_4g_mode_enabled中，

方便当下次进入界面时查询结果以显示开关的状态。继续看isnonttyorttyonvolteenabled()结果

public static boolean isnonttyorttyonvolteenabled(context context, int phoneid) {

    if (issupportmims() == false) {
        if (imsmanager.getbooleancarrierconfig(context,
                carrierconfigmanager.key_carrier_volte_tty_supported_bool)) {
            return true;
        }

        return settings.secure.getint(context.getcontentresolver(),
                settings.secure.preferred_tty_mode, telecommanager.tty_mode_off)
                == telecommanager.tty_mode_off;
    }

    imsmanager imsmanager = imsmanager.getinstance(context, phoneid);
    if(imsmanager != null) {
        return imsmanager.isnonttyorttyonvolteenabledforslot();
    } else {
        loge("isnonttyorttyonvolteenabled");
        loge("getinstance null for phoneid=" + phoneid);
    }

    return false;
}

从刚刚结论issupportmims()为false，主要看imsmanager.getbooleancarrierconfig()结果

源码位置 frameworks\opt\net\ims\src\java\com\android\ims\imsmanager.java

public static boolean getbooleancarrierconfig(context context, string key) {
    carrierconfigmanager configmanager = (carrierconfigmanager) context.getsystemservice(
            context.carrier_config_service);
    persistablebundle b = null;
    if (configmanager != null) {
        b = configmanager.getconfig();
    }
    if (b != null) {
        return b.getboolean(key);
    } else {
        // return static default defined in carrierconfigmanager.
        return carrierconfigmanager.getdefaultconfig().getboolean(key);
    }
}

从上面的代码可以看出，不论carrierconfigmanager是否为null，最终都是通过getboolean（）来读取key对应的结果，有点类似sharedprenference
还得继续往下深入，

carrierconfigmanager 源码位置 frameworks\base\telephony\java\android\telephony\carrierconfigmanager.java

 static {
    sdefaults = new persistablebundle();
    ...
    sdefaults.putboolean(key_carrier_volte_provisioning_required_bool, false);
    sdefaults.putboolean(key_carrier_volte_override_wfc_provisioning_bool, false);
    sdefaults.putboolean(key_carrier_volte_tty_supported_bool, true);

}

从中我们找到静态代码块设置初始值 key_carrier_volte_tty_supported_bool，默认值为true，回到 mtkimsmanager.java 中，

isnonttyorttyonvolteenabled()结果为true，则调用imsmanager.setadvanced4gmode(enabled)来打开或关闭volte。

进入imsmanager中，源码位置 frameworks\opt\net\ims\src\java\com\android\ims\imsmanager.java

public void setadvanced4gmode(boolean turnon) throws imsexception {
    checkandthrowexceptionifserviceunavailable();//bind ims_service，如果ims服务不可用则抛出异常

    // if turnon: first set feature values then call turnonims()
    // if turnoff: only set feature values if ims turn off is not allowed. if turn off is
    // allowed, first call turnoffims() then set feature values
    if (turnon) {
        setltefeaturevalues(turnon);
        log("setadvanced4gmode: turnonims");
        turnonims();//打开ims 服务
    } else {
        if (isimsturnoffallowed()) {
            log("setadvanced4gmode: turnoffims");
            turnoffims();//关闭ims 服务
        }
        setltefeaturevalues(turnon);
    }
}

打开ims服务

public void turnonims() throws imsexception {
    checkandthrowexceptionifserviceunavailable();

    try {
        mimsserviceproxy.turnonims();
    } catch (remoteexception e) {
        throw new imsexception("turnonims() ", e, imsreasoninfo.code_local_ims_service_down);
    }
}

通过mimsserviceproxy代理对象调用，代理对象的创建过程在createimsservice()中

/**
 * binds the ims service to make/receive the call. supports two methods of exposing an
 * imsservice:
 * 1) com.android.ims.imsservice implementation in servicemanager (deprecated).
 * 2) android.telephony.ims.imsservice implementation through imsresolver.
 */
protected void createimsservice() {
    if (!mconfigdynamicbind) {
        // old method of binding  
        rlog.i(tag, "creating imsservice using servicemanager");
        mimsserviceproxy = getserviceproxycompat();
    } else {
        rlog.i(tag, "creating imsservice using imsresolver");
        mimsserviceproxy = getserviceproxy();
    }
    // we have created a new imsservice connection, signal for re-registration
    synchronized (mhasregisteredlock) {
        mhasregisteredforproxy = false;
    }
}

此处创建mimsserviceproxy代理对象有两种方式，mconfigdynamicbind的值在framework/core/res/res/values/config.xml中定义，

通过查看该值为false，则通过getserviceproxycompat()获取mimsserviceproxy对象。

private imsserviceproxycompat getserviceproxycompat() {
    ibinder binder = servicemanager.checkservice(ims_service);

    if (binder != null) {
        try {
            binder.linktodeath(mdeathrecipient, 0);
        } catch (remoteexception e) {
        }
    }

    return new imsserviceproxycompat(mphoneid, binder);
}

imsserviceproxycompat的turnonims()方法

@override
public void turnonims() throws remoteexception {
    checkbinderconnection();
    getserviceinterface(mbinder).turnonims(mslotid);
}

实际上通过mbinder获取到iimsservice对象，继续跟进，实际上最终调用了iimsservice.aidl的turnonims()

源码位置 frameworks\base\telephony\java\com\android\ims\internal\iimsservice.aidl

interface iimsservice {
     ....

    /**
     * config interface to get/set ims service/capability parameters.
     */
    iimsconfig getconfiginterface(int phoneid);

    /**
     * used for turning on ims when its in off state.
     */
    void turnonims(int phoneid);

    /**
     * used for turning off ims when its in on state.
     * when ims is off, device will behave as csfb'ed.
     */
    void turnoffims(int phoneid);

    ....
}

回到上面在imsmanager.java中setadvanced4gmode()方法，不管打开或关闭都会调用setltefeaturevalues(turnon),来看下做了什么操作

protected void setltefeaturevalues(boolean turnon) {
    log("setltefeaturevalues: " + turnon);
    try {
        imsconfig config = getconfiginterface();
        if (config != null) {
            config.setfeaturevalue(imsconfig.featureconstants.feature_type_voice_over_lte,
                    telephonymanager.network_type_lte, turnon ? 1 : 0, mimsconfiglistener);

            if (isvolteenabledbyplatformforslot()) {
                boolean ignoredataenabledchanged = getbooleancarrierconfig(mcontext,
                        carrierconfigmanager.key_ignore_data_enabled_changed_for_video_calls);
                boolean enablevilte = turnon && isvtenabledbyuserforslot() &&
                        (ignoredataenabledchanged || isdataenabled());
                config.setfeaturevalue(imsconfig.featureconstants.feature_type_video_over_lte,
                        telephonymanager.network_type_lte,
                        enablevilte ? 1 : 0,
                        mimsconfiglistener);
            }
        }
    } catch (imsexception e) {
        loge("setltefeaturevalues: exception ", e);
    }
}

调用imsconfig的setfeaturevalue()保存值

源码位置 frameworks\base\telephony\java\com\android\ims\imsconfig.java

public void setfeaturevalue(int feature, int network, int value,
        imsconfiglistener listener) throws imsexception {
    if (dbg) {
        rlog.d(tag, "setfeaturevalue: feature = " + feature + ", network =" + network +
                ", value =" + value + ", listener =" + listener);
    }
    try {
        miconfig.setfeaturevalue(feature, network, value, listener);
    } catch (remoteexception e) {
        throw new imsexception("setfeaturevalue()", e,
                imsreasoninfo.code_local_service_unavailable);
    }
}

发现又调用的miconfig，继续接着找吧。调用过程：

imsconfig.java中setfeaturevalue()--->iimsconfig.aild--->

--->imsconfigimplbase.java(继承iimsconfig.aild)-->imsconfigimpl中的setfeaturevalue(继承imsconfigimplbase)-->imsconfigstorage中的setfeaturevalue

vendor\mediatek\proprietary\packages\services\ims\src\com\mediatek\ims\config\internal\imsconfigstorage.java

public void setfeaturevalue(int featureid, int network, int value)
        throws imsexception {
    synchronized(mfeaturelock) {
        mfeaturehelper.updatefeature(featureid, network, value);
    }
}

//当前类中的内部类 featurehelper
private static class featurehelper {

private void updatefeature(int featureid, int network, int value) {
        int curvalue = -1;
        boolean result = false;
        contentvalues cv = new contentvalues();
        cv.put(imsconfigcontract.feature.phone_id, mphoneid);
        cv.put(imsconfigcontract.feature.feature_id, featureid);
        cv.put(imsconfigcontract.feature.network_id, network);
        cv.put(imsconfigcontract.feature.value, value);

        // check exist or not
        try {
            curvalue = getfeaturevalue(featureid, network);
            if (debug) log.d(tag, "updatefeature() comparing: curvalue: " +
                    curvalue + ", value:" + value);
            if (!checkifbroadcastonce(featureid, mphoneid) || curvalue != value || curvalue == -1) {
                mcontentresolver.update(
                        imsconfigcontract.feature.geturiwithfeatureid(mphoneid, featureid, network),
                        cv, null, null);
            }
        } catch (imsexception e) {
            log.e(tag, "updatefeature() imsexception featureid:" + featureid +", value:" + value);
            mcontentresolver.insert(imsconfigcontract.feature.content_uri, cv);
        }
    }

}

参考链接

ims的注册流程分析

开关volte流程分析(一)