Doubts onPressed integration with Google Maps Flutter

Question

I set up a canvas and I’m having a hard time doing something On the buttons I wanted to put to work onPressed linked to the google maps API. Like, when I click on one of the buttons, it will tell me which are the nearest stores, however, since I’m a beginner, I’m having trouble doing this.

import 'package:flutter/material.dart';
import 'package:fluttertoast/fluttertoast.dart';

void main() => runApp(Materialapp(debugging()));

class Gridlayout extends Statelesswidget { List Events = [ "Clinic", "Petshop," "Pharmacy", "Indefinite." "Hospital SOS", "?" ];

@override Widget build(Buildcontext context) { Return Scaffold( body: Container( Décoration: Boxdecoration( image: Decorationimage ( image: Assetimage("Assets/bg.png"), fit: Boxfit.cover), Child: Container( margin: const Edgeinsets.only(top: 10), Child: Gridview( Physics: Bouncingscrollphysics(), gridDelegate: Slivergriddelegatewithfixedcrossaxiscount(crossAxisCount: 2), Children: Events.map((title) { Return Gesturedetector( Child: Card( Shape: Roundedrectangleborder(borderRadius: Borderradius.circular(100.0),), color: Colors.white60, margin: const Edgeinsets.all(20.0), Child: Flatbutton( onPressed: (){

                    } ,
                    child: getCardByTitle(title)),
              ),
              onTap: () {
                Fluttertoast.showToast(
                    msg: title,
                    toastLength: Toast.LENGTH_SHORT,
                    gravity: ToastGravity.CENTER,
                    backgroundColor: Colors.blueAccent,
                    textColor: Colors.white,
                    fontSize: 16.0);
              },
            );
          }).toList(),
        )),
  ),
);

}

Column getCardByTitle(String title) { String img = ""; if (title == "Clinic") img = "Assets/Clinic.png"; Else if (title == "Petshop") img = "Assets/petshop.png"; Else if (title == "Pharmacy") img = "Assets/farm.png"; Else if (title == "Undefined") img = "Assets/img3.png"; Else if (title == "SOS hospital") img = "Assets/Hosp.png"; Else img = "Assets/expert.png";

return Column( mainAxisAlignment: MainAxisAlignment.center, children: <Widget>[ Center( child: Container( child: Stack( children: <Widget>[ Image.asset( img, width: 50.0, height: 50.0, ) ], ), ), ), Text( title, style: TextStyle(fontSize: 20.0, fontWeight: FontWeight.bold), textAlign: TextAlign.center , ) ], );

} }