SMS Messaging in Android

SMS Messaging in Android

In the AndroidManifest.xml file, add the two permissions - SEND_SMS and RECEIVE_SMS:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="net.learn2develop.SMSMessaging"
      android:versionCode="1"
      android:versionName="1.0.0">
    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <activity android:name=".SMS"
                  android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>
    <uses-permission android:name="android.permission.SEND_SMS">
    </uses-permission>
    <uses-permission android:name="android.permission.RECEIVE_SMS">
    </uses-permission>
</manifest>
In the main.xml file located in the res/layout folder, add the following code so that the user can enter a phone number as well as a message to send:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Enter the phone number of recipient"
        />   
    <EditText
        android:id="@+id/txtPhoneNo"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"      
        />
    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"       
        android:text="Message"
        />   
    <EditText
        android:id="@+id/txtMessage"
        android:layout_width="fill_parent"
        android:layout_height="150px"
        android:gravity="top"       
        />        
    <Button
        android:id="@+id/btnSendSMS"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Send SMS"
        />  
</LinearLayout>

Next, in the SMS activity, we wire up the Button view so that when the user clicks on it, we will check to see that the phone number of the recipient and the message is entered before we send the message using the sendSMS() function, which we will define shortly:


package net.learn2develop.SMSMessaging;

import android.app.Activity;
import android.app.PendingIntent;
import android.content.Intent;
import android.os.Bundle;
import android.telephony.gsm.SmsManager;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class SMS extends Activity
{
    Button btnSendSMS;
    EditText txtPhoneNo;
    EditText txtMessage;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);      

        btnSendSMS = (Button) findViewById(R.id.btnSendSMS);
        txtPhoneNo = (EditText) findViewById(R.id.txtPhoneNo);
        txtMessage = (EditText) findViewById(R.id.txtMessage);

        btnSendSMS.setOnClickListener(new View.OnClickListener()
        {
            public void onClick(View v)
            {              
                String phoneNo = txtPhoneNo.getText().toString();
                String message = txtMessage.getText().toString();               
                if (phoneNo.length()>0 && message.length()>0)              
                    sendSMS(phoneNo, message);              
                else
                    Toast.makeText(getBaseContext(),
                        "Please enter both phone number and message.",
                        Toast.LENGTH_SHORT).show();
            }
        });      
    }  
}
The sendSMS() function is defined as follows:

public class SMS extends Activity
{
    //...

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        //...
    }

    //---sends an SMS message to another device---
    private void sendSMS(String phoneNumber, String message)
    {      
        PendingIntent pi = PendingIntent.getActivity(this, 0,
            new Intent(this, SMS.class), 0);              
        SmsManager sms = SmsManager.getDefault();
        sms.sendTextMessage(phoneNumber, null, message, pi, null);      
    }  
}