package com.example.gpstracking;

import android.app.Activity;
import android.os.Bundle;
import android.widget.EditText;

public class Otp extends Activity {

static EditText OtpNumber;

protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);

    setContentView(R.layout.otp_layout);

    OtpNumber = (EditText) findViewById(R.id.txtName);

}

public void recivedSms(String message) {

    try {

        OtpNumber.setText(message);

    } catch (Exception e) {

    }
    }

 package com.example.gpstracking;

 import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
 import android.os.Bundle;
 import android.telephony.SmsManager;
 import android.telephony.SmsMessage;
 import android.util.Log;
 import android.widget.Toast;

 public class IncomingSms extends BroadcastReceiver {
   @Override
     public void onReceive(Context context, Intent intent) {

    final Bundle bundle = intent.getExtras();

    try {

        if (bundle != null) {

            final Object[] pdusObj = (Object[]) bundle.get("pdus");

            for (int i = 0; i < pdusObj.length; i++) {

                SmsMessage currentMessage = SmsMessage
                        .createFromPdu((byte[]) pdusObj[i]);
                String phoneNumber = currentMessage
                        .getDisplayOriginatingAddress();
                String senderNum = phoneNumber;
                String message = currentMessage.getDisplayMessageBody();

                Log.v("gps", "--------------------------------message:"+message) ;

                Toast.makeText(context, message, 1).show() ;

                try {

                    if (senderNum.equals("TA-DOCOMO")) {

                        Otp Sms = new Otp();

                        Sms.recivedSms(message);
                    }

                } catch (Exception e) {

                    e.printStackTrace() ;
                }

            }
        }

    }
    catch (Exception e) {

        e.printStackTrace() ;

    }
}

}

public class AuthActivity extends AppCompatActivity implements OnMessageListener {
    private SmsInterceptor smsInterceptor;
    private EditText etAuthPassword;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_auth);
        initViews();
        initSmsInterceptor();
    }

    @Override
    protected void onResume() {
        super.onResume();
        smsInterceptor.register();
    }

    @Override
    protected void onPause() {
        super.onPause();
        smsInterceptor.unregister();
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        smsInterceptor.onRequestPermissionsResult(requestCode, permissions, grantResults);
    }

    @Override
    public void messageReceived(String message) {
        // You can perform your validation here
        etAuthPassword.setText(message);
    }

    private void initViews() {
        etAuthPassword = findViewById(R.id.etAuthPassword);
        etAuthPassword.addTextChangedListener(new SmsTextWatcher() {
            @Override
            public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
                if (charSequence.length() == 4) {
                    btnAuthPassword.setEnabled(true);
                    checkCode();
                } else {
                    btnAuthPassword.setEnabled(false);
                }
            }
        });
    }

    private void initSmsInterceptor() {
        smsInterceptor = new SmsInterceptor(this, this);
        // Not necessary
        smsInterceptor.setRegex(SMS_CODE_REGEX);
        smsInterceptor.setPhoneNumber(PHONE_NUMBER);
    }

    private void checkCode() {
        // Validation
        if (isValid) {
            navigateToMainScreen();
        }
    }
}