public class USSDService extends AccessibilityService {
public static String TAG = "USSDService";
public String responsee="";
@Override
public void onAccessibilityEvent(AccessibilityEvent event) {
    Log.d(TAG, "onAccessibilityEvent");
    String text = event.getText().toString();

    if (event.getClassName().equals("android.app.AlertDialog")) {
        performGlobalAction(GLOBAL_ACTION_BACK);
        Log.d(TAG, text);
        Intent intent = new Intent("message");
        intent.putExtra("value", text);
        Toast.makeText  (this,text,Toast.LENGTH_LONG).show();

        this.sendBroadcast(intent);// write a broad cast receiver and call sendbroadcast() from here, if you want to parse the message for balance, date
    }

}

@Override
public void onInterrupt() {
}

@Override
protected void onServiceConnected() {
    super.onServiceConnected();
    Log.d(TAG, "onServiceConnected");
    AccessibilityServiceInfo info = new AccessibilityServiceInfo();
    info.flags = AccessibilityServiceInfo.DEFAULT;
    info.packageNames = new String[]{"com.android.phone"};
    info.eventTypes = AccessibilityEvent.TYPE_WINDOW_STATE_CHANGED;
    info.feedbackType = AccessibilityServiceInfo.FEEDBACK_GENERIC;
    setServiceInfo(info);
}}

public class MainActivity extends AppCompatActivity {

private BroadcastReceiver bReceiver = new BroadcastReceiver(){

    @Override
    public void onReceive(Context context, Intent intent) {
        //put here whaterver you want your activity to do with the intent received
        Log.i("onReceive",intent.getStringExtra("value") );
    }
};

protected void onResume(){
    super.onResume();
    Log.i("onResume", "22222");
    LocalBroadcastManager.getInstance(this).registerReceiver(bReceiver, new IntentFilter("message"));
}

protected void onPause (){
    super.onPause();
    Log.i("onPause", "11111");

    LocalBroadcastManager.getInstance(this).unregisterReceiver(bReceiver);
}
@Override
protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);}}