Get Feedback after Sending a Message

package com.java2s.myapplication3.app;
/*www  .  ja  v  a2 s .  com*/
import android.app.Activity;
import android.app.PendingIntent;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.telephony.SmsManager;
import android.view.View;
import android.widget.Toast;

public class MainActivity extends Activity {
    String SENT = "SMS_SENT";
    String DELIVERED = "SMS_DELIVERED";
    PendingIntent sentPI, deliveredPI;
    BroadcastReceiver smsSentReceiver, smsDeliveredReceiver;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        sentPI = PendingIntent.getBroadcast(this, 0,
                new Intent(SENT), 0);

        deliveredPI = PendingIntent.getBroadcast(this, 0,
                new Intent(DELIVERED), 0);
    }

    @Override
    public void onResume() {
        super.onResume();

        smsSentReceiver = new BroadcastReceiver() {
            @Override
            public void onReceive(Context arg0, Intent arg1) {
                switch (getResultCode()) {
                    case Activity.RESULT_OK:
                        Toast.makeText(getBaseContext(), "SMS sent",
                                Toast.LENGTH_SHORT).show();
                        break;
                    case SmsManager.RESULT_ERROR_GENERIC_FAILURE:
                        Toast.makeText(getBaseContext(), "Generic failure",
                                Toast.LENGTH_SHORT).show();
                        break;
                    case SmsManager.RESULT_ERROR_NO_SERVICE:
                        Toast.makeText(getBaseContext(), "No service",
                                Toast.LENGTH_SHORT).show();
                        break;
                    case SmsManager.RESULT_ERROR_NULL_PDU:
                        Toast.makeText(getBaseContext(), "Null PDU",
                                Toast.LENGTH_SHORT).show();
                        break;
                    case SmsManager.RESULT_ERROR_RADIO_OFF:
                        Toast.makeText(getBaseContext(), "Radio off",
                                Toast.LENGTH_SHORT).show();
                        break;
                }
            }
        };

        //create the BroadcastReceiver when the SMS is delivered
        smsDeliveredReceiver = new BroadcastReceiver() {
            @Override
            public void onReceive(Context arg0, Intent arg1) {
                switch (getResultCode()) {
                    case Activity.RESULT_OK:
                        Toast.makeText(getBaseContext(), "SMS delivered",
                                Toast.LENGTH_SHORT).show();
                        break;
                    case Activity.RESULT_CANCELED:
                        Toast.makeText(getBaseContext(), "SMS not delivered",
                                Toast.LENGTH_SHORT).show();
                        break;
                }
            }
        };

        //register the two BroadcastReceivers
        registerReceiver(smsDeliveredReceiver, new IntentFilter(DELIVERED));
        registerReceiver(smsSentReceiver, new IntentFilter(SENT));
    }

    @Override
    public void onPause() {
        super.onPause();
        //unregister the two BroadcastReceivers
        unregisterReceiver(smsSentReceiver);
        unregisterReceiver(smsDeliveredReceiver);
    }

    public void onClick(View v) {
        sendSMS("5556", "Hello my friends!");
    }

    //sends an SMS message to another device
    private void sendSMS(String phoneNumber, String message) {
        SmsManager sms = SmsManager.getDefault();
        sms.sendTextMessage(phoneNumber, null, message, sentPI, deliveredPI);
    }
}