“Building Scalable Apps with Flutter and Golang: A Step-by-Step Guide”

Building a Powerful Combination: Flutter and Golang

When it comes to building fast, scalable, and efficient applications, two technologies stand out: Flutter and Golang. In this article, we’ll explore the benefits of using these two technologies together and provide a step-by-step guide on how to build a Flutter application that connects to a Golang backend.

Why Choose Flutter and Golang?

Flutter is a popular mobile framework that allows developers to build cross-platform applications with a single codebase. Its ease of use, flexibility, and performance make it an ideal choice for mobile app development.

Golang, on the other hand, is a modern programming language that’s gaining popularity due to its simplicity, reliability, and speed. Its compiled nature makes it faster than interpreted languages, and its concurrency features make it perfect for building scalable backends.

Prerequisites

Before we dive into the tutorial, make sure you have the following installed:

• Flutter
• Golang
• Heroku CLI (for deploying the backend)
• Knowledge of Flutter and Golang (this is not a beginner-friendly tutorial)

Building the Backend

Our backend will be a simple Golang server that generates a random image based on the request path. We’ll use the cameron library to generate the images.

Create a new directory for your backend and create a server.go file with the following code:
“`go
package main

import (
“fmt”
“log”
“net/http”
“github.com/cameron/go-cameron”
)

func main() {
port := os.Getenv(“PORT”)
if port == “” {
port = “3000”
}
http.HandleFunc(“/”, identicon)
log.Fatal(http.ListenAndServe(“:”+port, nil))
}

func identicon(w http.ResponseWriter, r *http.Request) {
path := r.URL.Path
img := cameron.GenerateImage(path)
w.Write(img)
}
“
Rungo mod initandgo mod tidyto initialize and install the required packages. Then, rungo run server.go` to start the server.

Deploying the Backend

Create a new file called Procfile with the following content:

web: go run server.go

Commit the changes and create a new Heroku app. Follow the instructions on the Deploy tab to deploy the app.

Building the Flutter App

Create a new Flutter project and replace the main.dart file with the following code:
“`dart
import ‘package:flutter/material.dart’;
import ‘package:http/http.dart’ as http;

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
title: ‘Random Image Generator’,
home: HomePage(),
);
}
}

class HomePage extends StatefulWidget {
@override
_HomePageState createState() => _HomePageState();
}

class _HomePageState extends State {
final _textController = TextEditingController();
String _imageUrl = ”;

void _generateImage() async {
final response = await http.get(Uri.parse(‘https://your-heroku-app-url.com/’ + _textController.text));
setState(() {
_imageUrl = response.body;
});
}

@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(‘Random Image Generator’),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
TextField(
controller: textController,
decoration: InputDecoration(
labelText: ‘Enter text’,
),
),
SizedBox(height: 20),
ElevatedButton(
onPressed: _generateImage,
child: Text(‘Generate Image’),
),
SizedBox(height: 20),
Image.network(imageUrl),
],
),
),
);
}
}
“
Replacehttps://your-heroku-app-url.com/` with the URL of your Heroku app.

Run flutter run to build and run the app. Enter some text in the input field and click the “Generate Image” button to see a random image generated based on the text.