@override

  Widget build(BuildContext context) {

    return new MaterialApp(

      home: new Scaffold(

        body: new Column(

          mainAxisAlignment: MainAxisAlignment.center,

          children: <Widget>[

            new Container(

                height: 250.0,

                child: new Stack(

                  children: <Widget>[

                    new Center(

                      child :

                       new Container(

                        child : new FloatingActionButton(

                            child : new Icon (Icons.location_on),

​

                            onPressed: ()

                            async {

​

                               SmsMessage message = new SmsMessage(_nirbinumber, '$loc1');    

                               sender.sendSms(message);

                               message.addStateListener((state) {

                               if (state == SmsMessageState.Delivered) {

                                 receiver.onSmsReceived.listen((SmsMessage msg) => _lastMessage = msg);

​

                                  setState(() {

                                    savegeoValue();    // function to extract GPS coordinate of the received sms and save it with "shared preference" 

                                    StreamSubscription<SmsMessage> _smsSubscription;

                                    }

                                  );

                                  showMap();   // function to launch googlemap view

                                 }

                                }

                              );

                            }

                        ),

                      ),

                    ),

                  ],

                )

            )

          ],

        )

    )

);

​