How to Invoke/Start an application when a call is ended?

Question

The code that I am presently using is as follows:

My main class

  public class Index extends  BroadcastReceiver{ 

        @Override
        public void onReceive(Context context, Intent intent) {

            TelephonyManager telephonyManager = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);
            telephonyManager.listen(new CustomPhoneStateListener(context), PhoneStateListener.LISTEN_CALL_STATE);
        }
    }

the CustomPhoneStateListener class

    public class CustomPhoneStateListener extends PhoneStateListener {

        public  Activity activ=new Activity(){
            public void startActivity(Intent i) {}
            };
            Context context; 
        public CustomPhoneStateListener(Context context) {
            super();
            this.context = context;
        }
        @Override
        public void onCallStateChanged(int state, String incomingNumber) {
            super.onCallStateChanged(state, incomingNumber);
           switch (state) {
            case TelephonyManager.CALL_STATE_IDLE:

                Toast.makeText(context, "call has ended", Toast.LENGTH_SHORT).show();
    // The process to transfer to the next application. 
                    Intent i = new Intent(Intent.ACTION_MAIN);
                PackageManager manager = activ.getPackageManager();
i = manager.getLaunchIntentForPackage("com.timetracker.app");// package  name for my new app
                i.addCategory(Intent.CATEGORY_LAUNCHER);
                activ.startActivity(i);
                break;
        case TelephonyManager.CALL_STATE_OFFHOOK:

                Toast.makeText(context, "Phone call has taken", Toast.LENGTH_SHORT).show();
                break;
            case TelephonyManager.CALL_STATE_RINGING:

                //when Ringing
                Toast.makeText(context, "Phone is ringing", Toast.LENGTH_SHORT).show();
                break;
                default:
                break;
            }
        }
    }

and the Android Manifest file as:

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

    <application android:icon="@drawable/icon" android:label="@string/app_name">
                <receiver android:name=".Index" >
                  <intent-filter>
               <action android:name="android.intent.action.PHONE_STATE"/>
               <action android:name="android.view.InputMethod" /> 
                </intent-filter>
                </receiver>
</application>

    <uses-permission android:name="android.permission.READ_PHONE_STATE" />
    <uses-permission android:name="android.permission.CALL_PHONE"/> 
</manifest>

By using the above code I am able to get the toast message for the respective actions that I am performing ,but I am not able to give any Intent or by using the Package_Manger I am not able to shift to the next app.

The log_cat message returned when trying to execute the code for invoking the app:

 D/AndroidRuntime(312): Shutting down VM
: W/dalvikvm(312): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
 FATAL EXCEPTION: main
  E/AndroidRuntime(312): java.lang.NullPointerException 
  E/AndroidRuntime(312):    at android.content.ContextWrapper.getPackageManager(ContextWrapper.java:85)
  E/AndroidRuntime(312):    at com.android.call.CustomPhoneStateListener.onCallStateChanged(CustomPhoneStateListener.java:39)
  E/AndroidRuntime(312):    at android.telephony.PhoneStateListener$2.handleMessage(PhoneStateListener.java:319)
  E/AndroidRuntime(312):    at android.os.Handler.dispatchMessage(Handler.java:99)
  E/AndroidRuntime(312):    at android.os.Looper.loop(Looper.java:123)
  E/AndroidRuntime(312):    at android.app.ActivityThread.main(ActivityThread.java:4627)
  E/AndroidRuntime(312):    at java.lang.reflect.Method.invokeNative(Native Method)
  E/AndroidRuntime(312):    at java.lang.reflect.Method.invoke(Method.java:521)
  E/AndroidRuntime(312):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
   E/AndroidRuntime(312):   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
   E/AndroidRuntime(312):   at dalvik.system.NativeStart.main(Native Method)

Answer 1

It looks like the problem is coming from the use of active declared like this:

    public  Activity activ=new Activity(){
        public void startActivity(Intent i) {}
    };

Here you're creating a new Activity without a context. Maybe you should just pass the Activity right into your CustomPhoneStateListener instead of the Context. Or use the context to get the PackageManager:

PackageManager manager = context.getPackageManager();

Answer 2

For this you need to listen for the Phone State. When you get call on your broadcast receiver then start this service and it will take care rest part of your handling.

public class MyPhoneStateListener extends Service{

@Override
public IBinder onBind(Intent arg0) {
    return null;
}

@Override
public void onCreate() {
    super.onCreate();
        StateListener phoneStateListener = new StateListener();
        TelephonyManager telephonymanager = (TelephonyManager)getSystemService(TELEPHONY_SERVICE);
        telephonymanager.listen(phoneStateListener, PhoneStateListener.LISTEN_CALL_STATE);
    }catch(Exception e){ }

}

class StateListener extends PhoneStateListener{
    @Override
    public void onCallStateChanged(int state, String incomingNumber) {
        super.onCallStateChanged(state, incomingNumber);
        switch(state){
            case TelephonyManager.CALL_STATE_RINGING:
                break;
            case TelephonyManager.CALL_STATE_OFFHOOK:
                break;
            case TelephonyManager.CALL_STATE_IDLE:
                //Here call your function to invoke another app.
                startAnotherApp(String pkgName);
                break;
        }
    }
};

private void startAnotherApp(String pkgName){
  Intent intent = getPackageManager().getLaunchIntentForPackage(packageName);
  intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
  intent.addFlags(Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED);
  if (null != intent) {
  try {
         startActivity(intent);
  } catch(Exception e) {  }
}

}

@Override
public void onDestroy() {

}

}

Permission:

<uses-permission android:name="android.permission.READ_PHONE_STATE" />