By Farhan Syah, CEO & Founder Biz Impulse

What Is Flutter?

Flutter is an open-source UI software development kit created by Google. It is used to develop applications for Android, iOS, Windows, Mac, Linux, Google Fuchsia, and the web. The first version of Flutter was known as codename “Sky” and ran on the Android 

A Bit Of Background

Flutter has been around since 2015 when Google introduced it and remained in beta before its official launch in December 2018. Since then, buzz around Flutter has grown stronger.

How was Flutter Made?

Flutter apps are built using Dart, a simple object-oriented programming language.

The central idea of Flutter revolves around widgets. The entire UI is made of combining different widgets, each of which defines a structural element (like a button or menu), a stylistic element (like a font or color scheme), an aspect of layout (like padding), and so on.

Flutter does not use OEM widgets, but provides its own ready-made widgets which look native either to Android (Material Design) or iOS apps (Cupertino). It’s also possible to create custom widgets. 

The Advantages Of Flutter

Without making any comparisons with other platforms, here’s a list of some of the features and qualities that may make you consider having a go at Flutter:

1. High Productivity

Since Flutter is cross-platform, you can use the same code base for your iOS and Android app. This can definitely save you both time and resources.

2. Great Performance

Dart compiles into native code and there is no need to access OEM widgets as Flutter has its own. This means less mediated communication between the app and the platform.

All of this contributes to fast app startup times and less performance issues.

4. Fast and simple development

One of the most lauded features of Flutter is hot reload which allows you to instantly view the changes made in the code on emulators, simulators and hardware.

In less than a second, the changed code is reloaded while the app is running with no need for a restart. This is great not just for building UIs or adding features but also for bug fixing. 

5. Compatibility

Since widgets are part of the app and not the platform, you’ll likely experience less or no compatibility issues on different OS versions. This in turn means less time spent on testing.

6. Open-source

Both Flutter and Dart are open-source and free to use, and provide extensive documentation and community support to help out with any issues you may encounter.

How About Dart?

What Is Dart?

Dart is the programming language used to code Flutter apps. Dart is another product by Google and released version 2.1, before Flutter, in November.

Dart looks a bit like C and is an object-oriented programming language. So, if you prefer the C languages or Java, Dart is the one for you, and you’ll likely be proficient in it.

Dart Functions

Dart is not only used for mobile app development but is a programming language. Approved as a standard by Ecma (ECMA-408), it’s used to build just about anything on the web, servers, desktop and of course, mobile applications. 

Dart, when used in web applications, is transpiled to JavaScript so it runs on all web browsers. The Dart installation comes with a VM as well to run the .dart files from a command-line interface. The Dart files used in Flutter apps are compiled and packaged into a binary file (.apk or .ipa) and uploaded to app stores.

What Does Coding In Dart Look Like?

1. Dart has type inference. The data type of a variable need not be explicitly declared, as Dart will “infer ”what it is. In Java, a variable needs to have its type explicitly given during declaration.

E.g.:

Dart	"Var something"
Java	"String something'

The code treats the variable according to whatever it contains, be it a number, string, bool or object. All data types are objects, including numbers. So, if left uninitialized, their default value is not a 0 but is instead null.

2. The keyword new used before the constructor for object creation is optional.

3. The super() method call is only at the end of a subclass’s constructor.

4. Method signatures can include a default value to the parameters passed. So, if one is not included in the method call, the method uses the default values instead.

5. It has a new inbuilt data type called Runes, that deal with UTF-32 code points in a string. For a simple example, see emojis and similar icons.