android - 唯一的设备ID

Question

Yes I took a look at all similar questions, however I found no suitable answer. I need the device ID to set test devices for AdMob. My 1st approach ( some digits changed due to security reasons ):

  final TelephonyManager tm = (TelephonyManager) c
            .getSystemService(Context.TELEPHONY_SERVICE);
   Log.w("ID", tm.getDeviceId());

The result: 358948074051795

Documentation says: Returns the unique device ID, for example, the IMEI for GSM and the MEID or ESN for CDMA phones. Return null if device ID is not available.

My 2nd approach:

   Log.w("ID_1",
            Secure.getString(c.getContentResolver(), Secure.ANDROID_ID));

The result: 98ade639139bf376

Description: A 64-bit number (as a hex string) that is randomly generated on the device's first boot and should remain constant for the lifetime of the device

The question: what is the difference? Which one should I use for AdMob test purposes?

Answer 1

The difference is written in the descriptions of both methods...
However, I think using IMEI number is much more reliable because it identifies the device itself. What if the device has to restore default configuration ?
You'd have to check if it doesn't generate a new number if you take your 2nd option.
More information about IMEI can be found here : http://en.wikipedia.org/wiki/International_Mobile_Equipment_Identity

Answer 2

1.Code

Settings.Secure#ANDROID_ID returns the Android ID as an unique 64-bit hex string

import android.provider.Settings.Secure;

String deviceId = Secure.getString(this.getContentResolver(),Secure.ANDROID_ID);

Toast.makeText(this, deviceId, Toast.LENGTH_SHORT).show();

2.manifest

Add uses-permission in manifest file

<uses-permission android:name="android.permission.READ_PHONE_STATE" />