CODEWITHSUNDEEP
android
Nikita
Nikita

Reputation: 199

Will TelephonyManager.getDeviceId work without a Sim Card?

i have a Simple Question :

Does 

 TelephonyManager.getDeviceId();

will work without Sim Card(SIM_STATE_ABSENT) in the Device ?

Upvotes: 5

Views: 2929

Answers (2)

StarPinkER
StarPinkER

Reputation: 14271

Code talks:

The telephony.getDeviceId() finally calls to Phone.getDeviceId(), the implementations of this method are different on different phone like CDMA Phone and GSM Phone. For example, CDMA Phone. 

public String getMeid() {
    return mMeid;
}
//returns MEID or ESN in CDMA
public String getDeviceId() {
    String id = getMeid();
    if ((id == null) || id.matches("^0*$")) {
        Rlog.d(LOG_TAG, "getDeviceId(): MEID is not initialized use ESN");
        id = getEsn();
    }
    return id;
}

It has no checks on that SIM ABSENT state. So of course you can get the result without a sim card.

However, take a look at when this mMeid is reset. 

case EVENT_GET_IMEI_DONE:
            ar = (AsyncResult)msg.obj;

            if (ar.exception != null) {
                break;
            }

            mImei = (String)ar.result;
case EVENT_RADIO_AVAILABLE: {
            mCM.getBasebandVersion(
                    obtainMessage(EVENT_GET_BASEBAND_VERSION_DONE));

            mCM.getIMEI(obtainMessage(EVENT_GET_IMEI_DONE));
            mCM.getIMEISV(obtainMessage(EVENT_GET_IMEISV_DONE));
        }

So it will get reset when it receives an EVENT_RADIO_AVAILABLE message. And that event is send from RIL. Only when it get an EVENT_RADIO_AVAILABLE message, it will send out a message to request device identity. Although the getting device identity has nothing to do with sim card, but EVENT_RADIO_AVAILABLE might do(need further confirmation).

I further check when will the system send out an EVENT_RADIO_AVAILABLE message. And finally found out that the RadioState contains:

enum RadioState {
    RADIO_OFF,         /* Radio explictly powered off (eg CFUN=0) */
    RADIO_UNAVAILABLE, /* Radio unavailable (eg, resetting or not booted) */
    SIM_NOT_READY,     /* Radio is on, but the SIM interface is not ready */
    SIM_LOCKED_OR_ABSENT,  /* SIM PIN locked, PUK required, network
                           personalization, or SIM absent */
    SIM_READY,         /* Radio is on and SIM interface is available */
    RUIM_NOT_READY,    /* Radio is on, but the RUIM interface is not ready */
    RUIM_READY,        /* Radio is on and the RUIM interface is available */
    RUIM_LOCKED_OR_ABSENT, /* RUIM PIN locked, PUK required, network
                              personalization locked, or RUIM absent */
    NV_NOT_READY,      /* Radio is on, but the NV interface is not available */
    NV_READY;          /* Radio is on and the NV interface is available */
    ...
}

and when isAvailable() returns true, it will send out the event. And the imei will get updated. 

public boolean isAvailable() {
    return this != RADIO_UNAVAILABLE;
}

So, SIM_ABSENT has nothing to do with device id.

Upvotes: 1

Anton Cherkashyn
Anton Cherkashyn

Reputation: 5859

It should work. I just tested this on my CDMA Galaxy nexus and it returned a value, even though it doesn't have a SIM card at all. When I ran it on an emulator, it returned a long string of zeroes.

Update: According to documentation, getDeviceId() returns IMEI for a GSM device. And IMEI is not a SIM-card feature, it comes with the device.

Upvotes: 2

Related Questions