Register Broadcastreceiver in manifest

Question

I have the following manifest.xml:

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">

    <receiver android:name=".PhoneStateBroadcastReceiver"
        android:permission="android.permission.READ_PHONE_STATE">
        <intent-filter>
            <action android:name="android.intent.action.PHONE_STATE" />
        </intent-filter>
    </receiver>

    <activity android:name=".MainActivity">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

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

</application>

The listener receives data while the main activity is running. However when the main activity is killed, the receiver stops to output information.

The receiver is an example class:

public class PhoneStateBroadcastReceiver extends BroadcastReceiver {

    private static final String TAG = "PhoneReceiver";
    Context mContext;
    String incoming_number;
    private int prev_state;

    @Override
    public void onReceive(Context context, Intent intent) {
        TelephonyManager telephony = (TelephonyManager)context.getSystemService(Context.TELEPHONY_SERVICE); //TelephonyManager object
        CustomPhoneStateListener customPhoneListener = new CustomPhoneStateListener();
        telephony.listen(customPhoneListener, PhoneStateListener.LISTEN_CALL_STATE); //Register our listener with TelephonyManager

        Bundle bundle = intent.getExtras();
        String phoneNr = bundle.getString("incoming_number");
        Log.v(TAG, phoneNr);
        Log.d( TAG, "!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!" );
        mContext = context;
    }

    /* Custom PhoneStateListener */
    public class CustomPhoneStateListener extends PhoneStateListener {

        private static final String TAG = "CustomStateListener";

        @Override
        public void onCallStateChanged(int state, String incomingNumber){

            if( incomingNumber != null && incomingNumber.length() > 0 )
                incoming_number = incomingNumber;

            switch(state){
                case TelephonyManager.CALL_STATE_RINGING:
                    Log.d(TAG, "CALL_STATE_RINGING");
                    prev_state=state;
                    break;

                case TelephonyManager.CALL_STATE_OFFHOOK:
                    Log.d(TAG, "CALL_STATE_OFFHOOK");
                    prev_state=state;
                    break;

                case TelephonyManager.CALL_STATE_IDLE:

                    Log.d(TAG, "CALL_STATE_IDLE==>"+incoming_number);

                    if((prev_state == TelephonyManager.CALL_STATE_OFFHOOK)){
                        prev_state=state;
                        //Answered Call which is ended
                    }
                    if((prev_state == TelephonyManager.CALL_STATE_RINGING)){
                        prev_state=state;
                        //Rejected or Missed call
                    }
                    break;
            }
        }
    }
}

As far as I understood the android principles, when a receiver is registered in manifest then it should receive data even if its app is killed, if so, what am I doing wrong?

Answer 1

OK. After banging my head against the wall for more than a week, I decided to create a new project with the minimum functionality and it worked from the first try. I don't know whether it was caused by something in my old code, which I doubt, since I copied it method by method to the new project and it still works, or the newer versions of Android Studio and their build tools.

Huge thanks to REG1 for having the patience and desire to give ideas.

Regards