Android SDK Tutorial: How To Send Text Messages

We are going to make a text messaging app: two text fields, one for the phone number and message and of course a send button. Pictures of the interface below.

and of course there will also be an error message if the user decides to try to be smart.

The JAVA file: SendSMSActivity.java

As always I think my comments in the code are pretty self explanatory, so I’ll just give you the code

package com.example.sendsms;

// import everything you need
import android.app.Activity;
import android.app.PendingIntent;
import android.content.Intent;
import android.os.Bundle;
import android.telephony.SmsManager;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class SendSMSActivity extends Activity {
	
    Button sendButton;
    EditText phoneTextField;
    EditText msgTextField;
   
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) 
    {
        super.onCreate(savedInstanceState);
        // load the layout
        setContentView(R.layout.main);        
 
        // make message text field object
        msgTextField = (EditText) findViewById(R.id.msgTextField);
        // make send button object
        sendButton = (Button) findViewById(R.id.sendButton);
        // make phone number field object
        phoneTextField = (EditText) findViewById(R.id.phoneTextField);
        
    }
    
    // this is the function that gets called when you click the button
    public void send(View v)
    {        
    	// get the phone number from the phone number text field
        String phoneNumber = phoneTextField.getText().toString();
        // get the message from the message text box
        String msg = msgTextField.getText().toString();  
        
        // make sure the fields are not empty
        if (phoneNumber.length()>0 && msg.length()>0)                
        {
        	// call the sms manager
            PendingIntent pi = PendingIntent.getActivity(this, 0,
                    new Intent(this, SendSMSActivity.class), 0);                
                SmsManager sms = SmsManager.getDefault();
                // this is the function that does all the magic
                sms.sendTextMessage(phoneNumber, null, msg, pi, null);  
        }
        else
        {
        	// display message if text fields are empty
            Toast.makeText(getBaseContext(),"All field are required",Toast.LENGTH_SHORT).show();
        }

        
    }  
}

The code can be easily modified to send automatic text messages.

The Layout File: main.xml

<?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:text="To Phone:"
        android:layout_width="fill_parent" 
        android:layout_height="wrap_content" 
        />     
    <EditText 
        android:id="@+id/phoneTextField"  
        android:layout_width="fill_parent" 
        android:layout_height="wrap_content"        
        />
    <TextView  
        android:text="Message"
        android:layout_width="fill_parent" 
        android:layout_height="wrap_content"         
        /> 
            
    <EditText 
        android:id="@+id/msgTextField"  
        android:layout_width="fill_parent" 
        android:layout_height="wrap_content"       
        />          
    <Button 
        android:text="Send"
        android:id="@+id/sendButton"  
        android:layout_width="fill_parent" 
        android:layout_height="wrap_content"
        android:onClick="send"
        /> 
        
</LinearLayout>

The Manifest File: AndroidManifest.xml

Notice the permission used to send sms, other than that it’s just the default manifest file.

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.example.sendsms"
      android:versionCode="1"
      android:versionName="1.0">
    <uses-sdk android:minSdkVersion="8" />

  	<uses-permission android:name="android.permission.SEND_SMS" />
  
    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <activity android:name=".SendSMSActivity"
                  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>
</manifest>