Question

I would like to implement an application for block a mobile number for receiving or sending calls and messages. In my application I am entering mobile number at EditText box then I am clicking a button for block the mobile number which has entered by the user.

I have implemented an activity class as follows:

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

        ((Button)findViewById(R.id.block)).setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                String mobileNumer = ((EditText)findViewById(R.id.mobileNum)).getText().toString();
                //How to block entered mobileNumber
            }
        });

        ((Button)findViewById(R.id.unblock)).setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                String mobileNumer = ((EditText)findViewById(R.id.mobileNum)).getText().toString();
                //How to unblock entered mobileNumber
            }
        });
    }
}

I think we may use BroadcastReceiver. But I don’t have more knowledge on it. Please give me an idea how to implement blocking or unblocking mobile number.
Please any body help me…..

Answer 1

create PhoneCallReceiver .java

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.telephony.PhoneStateListener;
import android.telephony.TelephonyManager;
import android.util.Log;
import android.widget.Toast;
public class PhoneCallReceiver extends BroadcastReceiver {  

@Override
public void onReceive(Context context, Intent intent) { 
    TelephonyManager telephony = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);
    PhoneCallStateListener customPhoneListener = new PhoneCallStateListener(context);
    telephony.listen(customPhoneListener, PhoneStateListener.LISTEN_CALL_STATE);



}}

now create PhoneCallStateListener .java

import java.lang.reflect.Method;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.media.AudioManager;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.telephony.PhoneStateListener;
import android.telephony.TelephonyManager;
import android.widget.Toast;

import com.android.internal.telephony.ITelephony;

public class PhoneCallStateListener extends PhoneStateListener {    

private Context context;
public PhoneCallStateListener(Context context){
    this.context = context;
}


@Override
public void onCallStateChanged(int state, String incomingNumber) {  
    SharedPreferences prefs=PreferenceManager.getDefaultSharedPreferences(context);

    switch (state) {

        case TelephonyManager.CALL_STATE_RINGING:       

              String block_number = prefs.getString("block_number", null);
            AudioManager audioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE); 
            //Turn ON the mute
            audioManager.setStreamMute(AudioManager.STREAM_RING, true);                 
            TelephonyManager telephonyManager = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);
            try {
                Toast.makeText(context, "in"+block_number, Toast.LENGTH_LONG).show();
                Class clazz = Class.forName(telephonyManager.getClass().getName());
                Method method = clazz.getDeclaredMethod("getITelephony");
                method.setAccessible(true);
                ITelephony telephonyService = (ITelephony) method.invoke(telephonyManager);     
                //Checking incoming call number
                System.out.println("Call "+block_number);

                if (incomingNumber.equalsIgnoreCase("+91"+block_number)) {
                    //telephonyService.silenceRinger();//Security exception problem
                     telephonyService = (ITelephony) method.invoke(telephonyManager);
                     telephonyService.silenceRinger();
                    System.out.println(" in  "+block_number);
                    telephonyService.endCall();
                }
            } catch (Exception e) {
                Toast.makeText(context, e.toString(), Toast.LENGTH_LONG).show();
            }
            //Turn OFF the mute     
            audioManager.setStreamMute(AudioManager.STREAM_RING, false);
            break;
        case PhoneStateListener.LISTEN_CALL_STATE:

    }
    super.onCallStateChanged(state, incomingNumber);
}}

Now in src create this package com.android.internal.telephony now in this package Right Click -> New -> File now give name ITelephony.aidl and paste this code

package com.android.internal.telephony; 

interface ITelephony {      

  boolean endCall();     

  void answerRingingCall();      

  void silenceRinger(); 
}

NOTE: Code is tested in Android 2.2 (Froyo),2.3 (GingerBread)