Click here to Skip to main content
11,926,429 members (59,994 online)
Click here to Skip to main content
Add your own
alternative version

Tagged as


23 bookmarked

Detecting incoming and outgoing phone calls on Android

, 13 Mar 2013 CPOL
Rate this:
Please Sign up or sign in to vote.
In this article I'll show you how to detect incoming and outgoing phone calls on the Android platform.


In this article I'll show you how to detect incoming and outgoing phone calls on the Android platform. It can be useful if you need to perform some action when a call is made. For example, to block it, to log it, or send call info to a server.

This article gives step-by-step instructions on how to create a simple demo app that will detect incoming and outgoing phone calls and show a "toast" message with phone number. You can extend and use this code for your own needs.

Incoming calls

For incoming calls we need to use the TelephonyManager class and its method listen to register a listener that will receive call state, data connection, network, SIM, and other events related to telephony. We are interested only in the call state notifications. This requires android.permission.READ_PHONE_STATE permission.

So, create our listener class derived from PhoneStateListener, and override the onCallStateChanged method, as follows:

* Listener to detect incoming calls. 
private class CallStateListener extends PhoneStateListener {
  public void onCallStateChanged(int state, String incomingNumber) {
      switch (state) {
          case TelephonyManager.CALL_STATE_RINGING:
          // called when someone is ringing to this phone
                  "Incoming: "+incomingNumber, 

Now I'll explain the onCallStateChanged method.

First argument - state is the call state, it can be CALL_STATE_RINGINGCALL_STATE_OFFHOOK, or CALL_STATE_IDLE. Ringing is the state when someone is calling us, offhook is when there is active or on hold call,  and idle is when nobody is calling us and there is no active call. We are interested in the ringing state.

Second argument - incomingNumber, it's the number who is calling us.

As shown in the code above, the listener shows the "toast" message with the phone number when an incoming call is ringing.

Next, get an instance of TelephonyManager and register the listener:

tm = (TelephonyManager) ctx.getSystemService(Context.TELEPHONY_SERVICE);
tm.listen(callStateListener, PhoneStateListener.LISTEN_CALL_STATE);

When the app is no longer need to receive notifications, it must unregister a listener by call:

tm.listen(callStateListener, PhoneStateListener.LISTEN_NONE);

Outgoing calls

For outgoing calls, the system sends a broadcast action android.intent.action.NEW_OUTGOING_CALL. We need to make a broadcast receiver, that will receive the intent with this action.

To receive this broadcast, the android.permission.PROCESS_OUTGOING_CALLS permission is required.

Create the broadcast receiver class:

* Broadcast receiver to detect the outgoing calls.
public class OutgoingReceiver extends BroadcastReceiver {
     public OutgoingReceiver() {

     public void onReceive(Context context, Intent intent) {
         String number = intent.getStringExtra(Intent.EXTRA_PHONE_NUMBER);
           "Outgoing: "+number, 

As with incoming calls, this code will show a "toast" message with phone number when there is an outgoing call.

Register the broadcast receiver:

IntentFilter intentFilter = new IntentFilter(Intent.ACTION_NEW_OUTGOING_CALL);
ctx.registerReceiver(outgoingReceiver, intentFilter);

We finished with the calls detection code. And now we need to create an activity that will enable/disable calls detection. It will be an activity with a simple UI, with a textview showing detection status, button to enable/disable detection, and exit button.

But here is another issue - when our activity loses focus, calls detection is disabled. To prevent this, we have to make a service that will run and that will enable detection on start, and disable on stop.

Create the service:

 * Call detect service. 
 * This service is needed, because MainActivity can lost it's focus,
 * and calls will not be detected.
 * @author Moskvichev Andrey V.
public class CallDetectService extends Service {
    private CallHelper callHelper;
    public CallDetectService() {

    public int onStartCommand(Intent intent, int flags, int startId) {
        callHelper = new CallHelper(this);
        int res = super.onStartCommand(intent, flags, startId);
        return res;
    public void onDestroy() {

    public IBinder onBind(Intent intent) {
        // not supporting binding
        return null;

Create the activity.

Get the UI elements and set the onclick button handlers:

public void onCreate(Bundle savedInstanceState) {
    textViewDetectState = (TextView) findViewById(;
    buttonToggleDetect = (Button) findViewById(;
    buttonToggleDetect.setOnClickListener(new OnClickListener() {
         public void onClick(View v) {
    buttonExit = (Button) findViewById(;
    buttonExit.setOnClickListener(new OnClickListener() {
         public void onClick(View v) {

Create the setDetectEnabled method that will toggle calls detection:

private void setDetectEnabled(boolean enable) {
    detectEnabled = enable;
    Intent intent = new Intent(this, CallDetectService.class);
    if (enable) {
          // start detect service 
          buttonToggleDetect.setText("Turn off");
    else {
          // stop detect service
          buttonToggleDetect.setText("Turn on");
          textViewDetectState.setText("Not detecting");


<manifest xmlns:android=""
    android:versionName="1.0" >

        android:targetSdkVersion="15" />
         Permissions required for calls detection.
    <uses-permission android:name="android.permission.READ_PHONE_STATE" />
    <uses-permission android:name="android.permission.PROCESS_OUTGOING_CALLS" />
        android:theme="@style/AppTheme" >
            android:label="@string/title_activity_main" >
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />

            android:exported="false" >



I showed you how to detect incoming and outgoing phone calls on Android. It is all quite simple. Please send me your comments and suggestions.

In the next articles, I'll show you other aspects of Android platform programming (networking, threads, multimedia processing, integration with websites and webservices, etc). You can download the latest version of the source code for this article at:


This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


About the Author

Andrey Moskvichev
CEO BitGriff LLC
Russian Federation Russian Federation
My name is Andrey Moskvichev.

I'm a software developer with more than 14 years of programming experience.

I specialize in networking, Unix systems (Linux, FreeBSD), mobile programming, computer graphics, software architecture, reverse engineering, data processing systems, AI, computer vision.

I'm interested in all new cutting edge technologies.

You may also be interested in...

Comments and Discussions

QuestionHow to detect the end of an outgoing call? Pin
Dismi12-Jan-15 1:16
memberDismi12-Jan-15 1:16 
QuestionGet a Web page title when incoming or outgoming calls Pin
memberPANOS MAMRMARAS3-Jan-15 8:22 
QuestionMy vote 5 Pin
WuRunZhe2-Sep-14 17:16
memberWuRunZhe2-Sep-14 17:16 
QuestionMy application crashing when using your code with a small addition of "writing to file" Pin
Member 1095618718-Jul-14 8:16
memberMember 1095618718-Jul-14 8:16 
AnswerRe: My application crashing when using your code with a small addition of "writing to file" Pin
Member 1095618718-Jul-14 10:00
memberMember 1095618718-Jul-14 10:00 
QuestionMultiple callbacks to onCallStateChanged() Pin
SLCompulsion26-Jun-14 7:44
memberSLCompulsion26-Jun-14 7:44 
QuestionDetect ringing state at outgoing call Pin
Member 1077727625-Jun-14 11:10
memberMember 1077727625-Jun-14 11:10 
GeneralMy vote of 5 Pin
Scyalsdk13-Jun-14 5:50
memberScyalsdk13-Jun-14 5:50 
QuestionAndroid Project Control incoming messages from certain numbers Pin
makhondi28-Oct-13 6:46
membermakhondi28-Oct-13 6:46 
AnswerRe: Android Project Control incoming messages from certain numbers Pin
Андрей Москвичёв30-Oct-13 21:32
professionalАндрей Москвичёв30-Oct-13 21:32 
Questioncorrection of code Pin
Isha Gupta1-Aug-13 0:59
memberIsha Gupta1-Aug-13 0:59 
AnswerRe: correction of code Pin
Андрей Москвичёв30-Oct-13 21:31
professionalАндрей Москвичёв30-Oct-13 21:31 
QuestionSome confusing Pin
duong217914-Jun-13 18:13
memberduong217914-Jun-13 18:13 
AnswerRe: Some confusing Pin
Андрей Москвичёв22-Jun-13 0:08
memberАндрей Москвичёв22-Jun-13 0:08 
Questionwhy incomming call detection dosen't use ctx.registerReceiver Pin
tieubuidoi12312-Jun-13 17:54
membertieubuidoi12312-Jun-13 17:54 
Questionwhy incomming call detection dosen't use ctx.registerReceiver Pin
tieubuidoi12312-Jun-13 17:54
membertieubuidoi12312-Jun-13 17:54 
AnswerRe: why incomming call detection dosen't use ctx.registerReceiver Pin
Андрей Москвичёв22-Jun-13 0:05
memberАндрей Москвичёв22-Jun-13 0:05 
QuestionThank you Pin
Jayarajantk29-Apr-13 23:30
memberJayarajantk29-Apr-13 23:30 
GeneralMy vote of 5 Pin
Sudhakar Shinde16-Mar-13 20:39
memberSudhakar Shinde16-Mar-13 20:39 
GeneralRe: My vote of 5 Pin
Андрей Москвичёв16-Mar-13 21:02
memberАндрей Москвичёв16-Mar-13 21:02 
GeneralMy vote of 5 Pin
Mihai MOGA11-Mar-13 22:50
memberMihai MOGA11-Mar-13 22:50 
This is a great inspiring article. I am pretty much pleased with your good work. You put really very helpful information. Keep it up once again.
GeneralRe: My vote of 5 Pin
Андрей Москвичёв12-Mar-13 8:19
memberАндрей Москвичёв12-Mar-13 8:19 

General General    News News    Suggestion Suggestion    Question Question    Bug Bug    Answer Answer    Joke Joke    Praise Praise    Rant Rant    Admin Admin   

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.

| Advertise | Privacy | Terms of Use | Mobile
Web03 | 2.8.151126.1 | Last Updated 13 Mar 2013
Article Copyright 2013 by Andrey Moskvichev
Everything else Copyright © CodeProject, 1999-2015
Layout: fixed | fluid