Flutter Hooks, say goodbye to StatefulWidget and reduce boilerplate code.

Flutter hooks have been available for a while now but they didn’t get a lot of love or visibility since then. I am wondering why, because they are awesome!

In this article I’ll try to show how you can reduce boilerplate and basically remove all the StatefulWidget you’re using today, and also how hooks are easy and cool to use!

First, what are hooks and where do they come from? Anyone?

Okay so they came originally from React (see https://medium.com/@dan_abramov/making-sense-of-react-hooks-fdbde8803889 to know more about them in a React context), I won’t bother you with React as I never used it and probably never will, so it’s not mandatory to know about React at all!

Hooks are a way to share the same code with multiple widgets, code that is usually duplicated or hard to share between stateful widgets. The way I describe them is “Hooks are UI logic management”.

I’ll present you the hooks I use the most in my apps and their stateful widgets equivalent for you to compare both and see what the gain actually is.

Memoized hook:

This hook is a simple way to cache an instance of an object during the lifecycle of your widget. Pretty handy to create your BLoC, MobX store or notifier objects for your screens.

Here is the stateful widget version:

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => new _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
  final store = MyStore();

  _MyHomePageState();

  @override
  Widget build(BuildContext context) {
    return Container();
  }
}

And now the hook version:

class MyHomePage extends HookWidget {
  @override
  Widget build(BuildContext context) {
    final store = useMemoized(() => MyStore());
    return Container();
  }
}

Both examples are doing the same job by just creating an instance of MyStore during the lifetime of the widget.

The gain here is not much, but generally you want to initialize your object to load the data for example, and for that Hooks got you covered too. Let’s see useEffect now!

#flutter #ui #dart #hooks

What is GEEK

Buddha Community

Flutter Hooks, say goodbye to StatefulWidget and reduce boilerplate code.

Destiny Volkman

1597014000

Google's Flutter 1.20 stable announced with new features - Navoki

Flutter Google cross-platform UI framework has released a new version 1.20 stable.

Flutter is Google’s UI framework to make apps for Android, iOS, Web, Windows, Mac, Linux, and Fuchsia OS. Since the last 2 years, the flutter Framework has already achieved popularity among mobile developers to develop Android and iOS apps. In the last few releases, Flutter also added the support of making web applications and desktop applications.

Last month they introduced the support of the Linux desktop app that can be distributed through Canonical Snap Store(Snapcraft), this enables the developers to publish there Linux desktop app for their users and publish on Snap Store. If you want to learn how to Publish Flutter Desktop app in Snap Store that here is the tutorial.

Flutter 1.20 Framework is built on Google’s made Dart programming language that is a cross-platform language providing native performance, new UI widgets, and other more features for the developer usage.

Here are the few key points of this release:

Performance improvements for Flutter and Dart

In this release, they have got multiple performance improvements in the Dart language itself. A new improvement is to reduce the app size in the release versions of the app. Another performance improvement is to reduce junk in the display of app animation by using the warm-up phase.

sksl_warm-up

If your app is junk information during the first run then the Skia Shading Language shader provides for pre-compilation as part of your app’s build. This can speed it up by more than 2x.

Added a better support of mouse cursors for web and desktop flutter app,. Now many widgets will show cursor on top of them or you can specify the type of supported cursor you want.

Autofill for mobile text fields

Autofill was already supported in native applications now its been added to the Flutter SDK. Now prefilled information stored by your OS can be used for autofill in the application. This feature will be available soon on the flutter web.

flutter_autofill

A new widget for interaction

InteractiveViewer is a new widget design for common interactions in your app like pan, zoom drag and drop for resizing the widget. Informations on this you can check more on this API documentation where you can try this widget on the DartPad. In this release, drag-drop has more features added like you can know precisely where the drop happened and get the position.

Updated Material Slider, RangeSlider, TimePicker, and DatePicker

In this new release, there are many pre-existing widgets that were updated to match the latest material guidelines, these updates include better interaction with Slider and RangeSlider, DatePicker with support for date range and time picker with the new style.

flutter_DatePicker

New `pubspec.yaml` format

Other than these widget updates there is some update within the project also like in pubspec.yaml file format. If you are a flutter plugin publisher then your old pubspec.yaml is no longer supported to publish a plugin as the older format does not specify for which platform plugin you are making. All existing plugin will continue to work with flutter apps but you should make a plugin update as soon as possible.

Preview of embedded Dart DevTools in Visual Studio Code

Visual Studio code flutter extension got an update in this release. You get a preview of new features where you can analyze that Dev tools in your coding workspace. Enable this feature in your vs code by _dart.previewEmbeddedDevTools_setting. Dart DevTools menu you can choose your favorite page embed on your code workspace.

Network tracking

The updated the Dev tools comes with the network page that enables network profiling. You can track the timings and other information like status and content type of your** network calls** within your app. You can also monitor gRPC traffic.

Generate type-safe platform channels for platform interop

Pigeon is a command-line tool that will generate types of safe platform channels without adding additional dependencies. With this instead of manually matching method strings on platform channel and serializing arguments, you can invoke native class and pass nonprimitive data objects by directly calling the Dartmethod.

There is still a long list of updates in the new version of Flutter 1.2 that we cannot cover in this blog. You can get more details you can visit the official site to know more. Also, you can subscribe to the Navoki newsletter to get updates on these features and upcoming new updates and lessons. In upcoming new versions, we might see more new features and improvements.

You can get more free Flutter tutorials you can follow these courses:

#dart #developers #flutter #app developed #dart devtools in visual studio code #firebase local emulator suite in flutter #flutter autofill #flutter date picker #flutter desktop linux app build and publish on snapcraft store #flutter pigeon #flutter range slider #flutter slider #flutter time picker #flutter tutorial #flutter widget #google flutter #linux #navoki #pubspec format #setup flutter desktop on windows

Terry Tremblay

1598396940

What is Flutter and why you should learn it?

Flutter is an open-source UI toolkit for mobile developers, so they can use it to build native-looking** Android and iOS** applications from the same code base for both platforms. Flutter is also working to make Flutter apps for Web, PWA (progressive Web-App) and Desktop platform (Windows,macOS,Linux).

flutter-mobile-desktop-web-embedded_min

Flutter was officially released in December 2018. Since then, it has gone a much stronger flutter community.

There has been much increase in flutter developers, flutter packages, youtube tutorials, blogs, flutter examples apps, official and private events, and more. Flutter is now on top software repos based and trending on GitHub.

Flutter meaning?

What is Flutter? this question comes to many new developer’s mind.

humming_bird_dart_flutter

Flutter means flying wings quickly, and lightly but obviously, this doesn’t apply in our SDK.

So Flutter was one of the companies that were acquired by **Google **for around $40 million. That company was based on providing gesture detection and recognition from a standard webcam. But later when the Flutter was going to release in alpha version for developer it’s name was Sky, but since Google already owned Flutter name, so they rename it to Flutter.

Where Flutter is used?

Flutter is used in many startup companies nowadays, and even some MNCs are also adopting Flutter as a mobile development framework. Many top famous companies are using their apps in Flutter. Some of them here are

Dream11

NuBank

Reflectly app

Abbey Road Studios

and many more other apps. Mobile development companies also adopted Flutter as a service for their clients. Even I was one of them who developed flutter apps as a freelancer and later as an IT company for mobile apps.

Flutter as a service

#dart #flutter #uncategorized #flutter framework #flutter jobs #flutter language #flutter meaning #flutter meaning in hindi #google flutter #how does flutter work #what is flutter

Aliyah Satterfield

1591643580

Adobe XD plugin for Flutter with CodePen Tutorial

Recently Adobe XD releases a new version of the plugin that you can use to export designs directly into flutter widgets or screens. Yes, you read it right, now you can make and export your favorite design in Adobe XD and export all the design in the widget form or as a full-screen design, this can save you a lot of time required in designing.

What we will do?
I will make a simple design of a dialogue box with a card design with text over it as shown below. After you complete this exercise you can experiment with the UI. You can make your own components or import UI kits available with the Adobe XD.

#developers #flutter #adobe xd design export to flutter #adobe xd flutter code #adobe xd flutter code generator - plugin #adobe xd flutter plugin #adobe xd flutter plugin tutorial #adobe xd plugins #adobe xd to flutter #adobe xd tutorial #codepen for flutter.

Hertha Mayer

1594721048

Flutter Hooks, say goodbye to StatefulWidget and reduce boilerplate code.

Flutter hooks have been available for a while now but they didn’t get a lot of love or visibility since then. I am wondering why, because they are awesome!

In this article I’ll try to show how you can reduce boilerplate and basically remove all the StatefulWidget you’re using today, and also how hooks are easy and cool to use!

First, what are hooks and where do they come from? Anyone?

Okay so they came originally from React (see https://medium.com/@dan_abramov/making-sense-of-react-hooks-fdbde8803889 to know more about them in a React context), I won’t bother you with React as I never used it and probably never will, so it’s not mandatory to know about React at all!

Hooks are a way to share the same code with multiple widgets, code that is usually duplicated or hard to share between stateful widgets. The way I describe them is “Hooks are UI logic management”.

I’ll present you the hooks I use the most in my apps and their stateful widgets equivalent for you to compare both and see what the gain actually is.

Memoized hook:

This hook is a simple way to cache an instance of an object during the lifecycle of your widget. Pretty handy to create your BLoC, MobX store or notifier objects for your screens.

Here is the stateful widget version:

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => new _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
  final store = MyStore();

  _MyHomePageState();

  @override
  Widget build(BuildContext context) {
    return Container();
  }
}

And now the hook version:

class MyHomePage extends HookWidget {
  @override
  Widget build(BuildContext context) {
    final store = useMemoized(() => MyStore());
    return Container();
  }
}

Both examples are doing the same job by just creating an instance of MyStore during the lifetime of the widget.

The gain here is not much, but generally you want to initialize your object to load the data for example, and for that Hooks got you covered too. Let’s see useEffect now!

#flutter #ui #dart #hooks

Tyrique Littel

1604008800

Static Code Analysis: What It Is? How to Use It?

Static code analysis refers to the technique of approximating the runtime behavior of a program. In other words, it is the process of predicting the output of a program without actually executing it.

Lately, however, the term “Static Code Analysis” is more commonly used to refer to one of the applications of this technique rather than the technique itself — program comprehension — understanding the program and detecting issues in it (anything from syntax errors to type mismatches, performance hogs likely bugs, security loopholes, etc.). This is the usage we’d be referring to throughout this post.

“The refinement of techniques for the prompt discovery of error serves as well as any other as a hallmark of what we mean by science.”

J. Robert Oppenheimer

Outline

We cover a lot of ground in this post. The aim is to build an understanding of static code analysis and to equip you with the basic theory, and the right tools so that you can write analyzers on your own.

We start our journey with laying down the essential parts of the pipeline which a compiler follows to understand what a piece of code does. We learn where to tap points in this pipeline to plug in our analyzers and extract meaningful information. In the latter half, we get our feet wet, and write four such static analyzers, completely from scratch, in Python.

Note that although the ideas here are discussed in light of Python, static code analyzers across all programming languages are carved out along similar lines. We chose Python because of the availability of an easy to use ast module, and wide adoption of the language itself.

How does it all work?

Before a computer can finally “understand” and execute a piece of code, it goes through a series of complicated transformations:

static analysis workflow

As you can see in the diagram (go ahead, zoom it!), the static analyzers feed on the output of these stages. To be able to better understand the static analysis techniques, let’s look at each of these steps in some more detail:

Scanning

The first thing that a compiler does when trying to understand a piece of code is to break it down into smaller chunks, also known as tokens. Tokens are akin to what words are in a language.

A token might consist of either a single character, like (, or literals (like integers, strings, e.g., 7, Bob, etc.), or reserved keywords of that language (e.g, def in Python). Characters which do not contribute towards the semantics of a program, like trailing whitespace, comments, etc. are often discarded by the scanner.

Python provides the tokenize module in its standard library to let you play around with tokens:

Python

1

import io

2

import tokenize

3

4

code = b"color = input('Enter your favourite color: ')"

5

6

for token in tokenize.tokenize(io.BytesIO(code).readline):

7

    print(token)

Python

1

TokenInfo(type=62 (ENCODING),  string='utf-8')

2

TokenInfo(type=1  (NAME),      string='color')

3

TokenInfo(type=54 (OP),        string='=')

4

TokenInfo(type=1  (NAME),      string='input')

5

TokenInfo(type=54 (OP),        string='(')

6

TokenInfo(type=3  (STRING),    string="'Enter your favourite color: '")

7

TokenInfo(type=54 (OP),        string=')')

8

TokenInfo(type=4  (NEWLINE),   string='')

9

TokenInfo(type=0  (ENDMARKER), string='')

(Note that for the sake of readability, I’ve omitted a few columns from the result above — metadata like starting index, ending index, a copy of the line on which a token occurs, etc.)

#code quality #code review #static analysis #static code analysis #code analysis #static analysis tools #code review tips #static code analyzer #static code analysis tool #static analyzer

Flutter Hooks, say goodbye to StatefulWidget and reduce boilerplate code.

Memoized hook:

What is GEEK

Buddha Community

Google's Flutter 1.20 stable announced with new features - Navoki

Performance improvements for Flutter and Dart

Autofill for mobile text fields

Updated Material Slider, RangeSlider, TimePicker, and DatePicker

New pubspec.yaml format

Preview of embedded Dart DevTools in Visual Studio Code

Network tracking

Generate type-safe platform channels for platform interop

What is Flutter and why you should learn it?

Flutter meaning?

Where Flutter is used?

Dream11

NuBank

Reflectly app

Abbey Road Studios

Adobe XD plugin for Flutter with CodePen Tutorial

Flutter Hooks, say goodbye to StatefulWidget and reduce boilerplate code.

Memoized hook:

Static Code Analysis: What It Is? How to Use It?

Outline

How does it all work?

Scanning

New `pubspec.yaml` format