How do I programmatically access the value shown in the image below ?

How do I programmatically access the value shown in the image below ?

 
    
     
    
    This is the hardware serial number. To access it on
Android Q  (>= SDK 29)
android.Manifest.permission.READ_PRIVILEGED_PHONE_STATE is required. Only system apps can require this permission. If the calling package is the device or profile owner then the READ_PHONE_STATE permission suffices.
Android 8 and later (>= SDK 26) use android.os.Build.getSerial() which requires the dangerous permission READ_PHONE_STATE. Using android.os.Build.SERIAL returns android.os.Build.UNKNOWN.
Android 7.1 and earlier (<= SDK 25) and earlier android.os.Build.SERIAL does return a valid serial.
It's unique for any device. If you are looking for possibilities on how to get/use a unique device id you should read here.
For a solution involving reflection without requiring a permission see this answer.
 
    
    Until Android 7.1 you will get it with:
Build.SERIAL
On Android 8 (SDK 26) and above, this field will return UNKNOWN and must be accessed with:
Build.getSerial()
which requires the dangerous permission
android.permission.READ_PHONE_STATE.
Since Android Q using Build.getSerial() gets a bit more complicated by requiring:
android.Manifest.permission.READ_PRIVILEGED_PHONE_STATE (which can only be acquired by system apps), or for the calling package to be the device or profile owner and have the READ_PHONE_STATE permission. This means most apps won't be able to uses this feature. See the Android Q announcement from Google.
If you just require a unique identifier, it's best to avoid using hardware identifiers as Google continuously tries to make it harder to access them for privacy reasons. You could just generate a UUID.randomUUID().toString(); and save it the first time it needs to be accessed in e.g. shared preferences. Alternatively you could use ANDROID_ID which is a 8 byte long hex string unique to the device, user and (only Android 8+) app installation. For more info on that topic, see Best practices for unique identifiers.
 
    
    Build.SERIAL can be empty or sometimes return a different value (proof 1, proof 2) than what you can see in your device's settings.
If you want a more complete and robust solution, I've compiled every possible solution I could found in a single gist. Here's a simplified version of it :
public static String getSerialNumber() {
    String serialNumber;
    try {
        Class<?> c = Class.forName("android.os.SystemProperties");
        Method get = c.getMethod("get", String.class);
        serialNumber = (String) get.invoke(c, "gsm.sn1");
        if (serialNumber.equals(""))
            serialNumber = (String) get.invoke(c, "ril.serialnumber");
        if (serialNumber.equals(""))
            serialNumber = (String) get.invoke(c, "ro.serialno");
        if (serialNumber.equals(""))
            serialNumber = (String) get.invoke(c, "sys.serialnumber");
        if (serialNumber.equals(""))
            serialNumber = Build.SERIAL;
        // If none of the methods above worked
        if (serialNumber.equals(""))
            serialNumber = null;
    } catch (Exception e) {
        e.printStackTrace();
        serialNumber = null;
    }
    return serialNumber;
}
I try to update the gist regularly whenever I can test on a new device or Android version. Contributions are welcome too.
 
    
    From Android P, defining the READ_PHONE_STATE permission in AndroidManifest only, will not work. We have to actually request for the permission. Below code works for me:
@RequiresApi(api = Build.VERSION_CODES.P)
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_PHONE_STATE) != PackageManager.PERMISSION_GRANTED) {
        ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.READ_PHONE_STATE}, 101);
    }
}
@RequiresApi(api = Build.VERSION_CODES.O)
@Override
protected void onResume() {
    super.onResume();
    if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_PHONE_STATE) != PackageManager.PERMISSION_GRANTED) {
        return;
    }
    Log.d(TAG,Build.getSerial());
}
@RequiresApi(api = Build.VERSION_CODES.O)
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
    switch (requestCode) {
        case 101:
            if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
            if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_PHONE_STATE) != PackageManager.PERMISSION_GRANTED) {
                return;
            }
        } else {
            //not granted
        }
        break;
        default:
            super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    }
}
Add this permissions in AndroidManifest.xml
<uses-permission android:name = "android.permission.INTERNET"/>
<uses-permission android:name = "android.permission.READ_PHONE_STATE" />
I like my solution:
/**
 * Checks some permission
 *
 * @return true - If have any of the permissions sent by parameter
 * @return true - If you do not have any of the permissions sent by parameter
 */
fun Context.hasPermissionSome(vararg permissions: String): Boolean {
    permissions.forEach { permission ->
        if (hasPermission(permission)) {
            return true
        }
    }
    return false
}
@CheckResult
fun validateValue(value: String?, valueToCompare: String? = null): Boolean {
    if (!value.isNullOrEmpty() && value != Build.UNKNOWN && value != valueToCompare)
        return true
    return false
}
/**
 * @see: https://developer.android.com/about/versions/10/privacy/changes#data-ids
 *
 * Retrieve SerialNumber with system commands:
 *   adb shell getprop ro.serialno
 *   adb shell getprop ro.boot.serialno
 *   adb shell getprop ril.serialnumber
 * @return device Serial Number obtained with SystemProperties
 */
@SuppressLint("PrivateApi")
private fun serialNumberBySysProp(): String? {
    var sn: String? = null
    val readPhonePermissions = arrayOf(
        Manifest.permission.READ_PHONE_STATE,
        "android.permission.READ_PRIVILEGED_PHONE_STATE"
    )
    if (!this.context.hasPermissionSome(*readPhonePermissions))
        return sn
    try {
        val systemProps = Class.forName("android.os.SystemProperties")
        val getProp = systemProps.getMethod("get", String::class.java)
        
        // 1ª tentativa
        sn = getProp("ril.serialnumber") as String?
        if (validateValue(sn)) {
            return sn
        }
        // 2ª tentativa
        sn = getProp("ro.serialno") as String?
        if (validateValue(sn)) {
            return sn
        }
        // 3ª tentativa
        sn = getProp("ro.boot.serialno") as String?
        if (validateValue(sn)) {
            return sn
        }
        // 4ª tentativa
        sn = getProp("sys.serialnumber") as String?
        if (validateValue(sn)) {
            return sn
        }
    } catch (e: Exception) { }
    return if (validateValue(sn))
        sn
    else
        null
}
/**
 * @return device Serial Number obtained with Build Class
 */
@SuppressLint("HardwareIds")
private fun serialNumberByBuild(): String? {
    var sn: String? = null
    MediaDrm.PROPERTY_DEVICE_UNIQUE_ID
    if (!this.context.hasPermissionSome(
            Manifest.permission.READ_PHONE_STATE,
            "android.permission.READ_PRIVILEGED_PHONE_STATE"
        ))
        return sn
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
        sn = Build.getSerial()
    } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
        sn = Build.getSerial()
    } else if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.N_MR1) {
        sn = Build.getSerial()
        if (!validateValue(sn))
            sn = Build.SERIAL
    }
    return if (validateValue(sn))
        sn
    else
        null
}
val serialNumber: String
    @SuppressLint("HardwareIds", "PrivateApi", "MissingPermission", "StaticFieldLeak")
    get() {
        var serial: String = serialNumberByBuild() ?: ""
        if (!validateValue(serial)) {
            serial = serialNumberBySysProp() ?: ""
        }
        return serial
    }
Add this permissions in AndroidManifest.xml
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
 
    
    if you want something that works on newer android versions and android emulator, This might help:
Note: don't forget to give necessary permissions. (Might not work in android 11 and 12 without system level permissions)
fun getSerialNumber(): String {
    var serialNumber: String?
    try {
        val c = Class.forName("android.os.SystemProperties")
        val get = c.getMethod("get", String::class.java)
        serialNumber = get.invoke(c, "gsm.sn1") as String
        if (serialNumber == "") serialNumber = get.invoke(c, "ril.serialnumber") as String
        if (serialNumber == "") serialNumber = get.invoke(c, "ro.serialno") as String
        if (serialNumber == "") serialNumber = get.invoke(c, "sys.serialnumber") as String
        if (serialNumber == "") serialNumber = get.invoke(c, "ro.boot.serialno") as String
        if (serialNumber == "") serialNumber = get.invoke(c, "ro.kernel.androidboot.serialno") as String
        if (serialNumber == "") {
            serialNumber = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
                Build.getSerial()
            } else {
                Build.SERIAL
            }
        }
        // If none of the methods above worked
        if (serialNumber == "") serialNumber = null
    } catch (e: Exception) {
        e.printStackTrace()
        serialNumber = null
    }
    if (!serialNumber.isNullOrEmpty() && serialNumber != Build.UNKNOWN) {
        return serialNumber
    }
    return "TEMP12345678"
}
