Sarama Demsas

Sarama Demsas

1607074200

A Flutter Widget to use Apache ECharts

A Flutter widget to use Apache ECharts (incubating) in a reactive way.

bar boxplot effectScatter funnel gague geo graph heatmap kline line liquid map parallel pie radar scatter wordCloud bar3D line3D sankey scatter3D surface3D themeRiver overlap

Features

Note: flutter_echarts focuses on complex charts and interactions. It’s implemented by WebView. If you prefer better performance and capability but simpler charts, we recommend this pure Flutter visualization lib: Graphic

Reactive Updating

The most exciting feature of Flutter widgets and React components is that the view can update reactively when data changes. Thanks to ECharts’ data driven architecture, flutter_echarts implements a reactive way to connect charts with data. The charts automatically re-render when data in the option property changes.

Two Way Communication

The onMessage and extraScript properties provide a way to set two-way event communication between Flutter and JavaScript.

Configurable Extensions

ECharts has a lot of extensions. The extensions property allows you to inject the extension scripts as raw strings. In this way, you can copy these scripts to your source code without being confusing by assets dirs.

Installing

Add this to your package’s pubspec.yaml file:

dependencies:
  flutter_echarts: #latest version

Now in your Dart code, you can use:

import 'package:flutter_echarts/flutter_echarts.dart';  

Details see pub.dev.

Usage

The flutter_echarts package itself is very simple to use, just like a common statelessWidget:

Details about the option object is in the Echarts docs or Echarts examples.

Container(
  child: Echarts(
  option: '''
    {
      xAxis: {
        type: 'category',
        data: ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun']
      },
      yAxis: {
        type: 'value'
      },
      series: [{
        data: [820, 932, 901, 934, 1290, 1330, 1320],
        type: 'line'
      }]
    }
  ''',
  ),
  width: 300,
  height: 250,
)

See the full flutter_echarts_example.

Widget Properties

option

String

( required )

ECharts is mainly configured by passing a string value to the JavaScript option property.

You can use jsonEncode() function in dart:convert to convert data in Dart object form:

source: ${jsonEncode(_data1)},

Because JavaScript don’t have ''', you can use this operator to reduce some escape operators for quotas:

Echarts(
  option: '''

    // option string

  ''',
),

To use images in option properties, we suggest the Base64 Data URL :

image: 'data:image/png;base64,iVBORw0KG...',

extraScript

String

JavaScript which will execute after the Echarts.init() and before any chart.setOption(). The widget has a Javascript channel named Messager, so you can use this identifier to send messages from JavaScript to Flutter:

extraScript: '''
  chart.on('click', (params) => {
    if(params.componentType === 'series') {
        Messager.postMessage('anything');
    }
  });
''',

onMessage

void Function(String)

Function to handle the message sent by Messager.postMessage() in extraScript .

extensions

List<String>

List of strings are from Echarts extensions, such as themes, components, WebGL, and languages. You can download them from the official ECharts extension list. Insert extensions as raw strings:

const liquidPlugin = r'''

  // copy from liquid.min.js

''';

theme

String

You can download built-in ECharts themes or build your own custom themes with the ECharts theme builder. Copy the theme script into the extensions param and register the theme name with this param.

captureAllGestures

bool

( default: false )

Setting captureAllGestures to true is useful when handling 3D rotation and data zoom bars. Note that setting prevents containers like ListViews from reacting to gestures on the charts.

If true, captureHorizontalGestures and captureVerticalGestures are forced true.

captureHorizontalGestures

bool

( default: false )

Only capture horizontal gestures.

captureVerticalGestures

bool

( default: false )

Only capture vertical gestures.

onLoad

void Function()

The callback when first time the chart is loaded and rendered.

Blog

Reactive Echarts Flutter Widget

A performance optimization of Flutter WebView

If you have any suggestions or requests, please open an issue.

The gallery GIF is from chenjiandongx

Download Details:

Author: entronad

Source Code: https://github.com/entronad/flutter_echarts

#flutter #dart #mobile-apps

What is GEEK

Buddha Community

A Flutter Widget to use Apache ECharts

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 RangeSliderDatePicker 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

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

Dream11

NuBank

NuBank

Reflectly app

Reflectly app

Abbey Road Studios

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

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.

Elliott  Owen

Elliott Owen

1626909900

Exploring Flutter Widgets || Flutter Container Widget & Its Properties #15

In this video I have discussed about Container widget and its different properties.

It is a widget which is used to hold the child widget with the ability to apply some styling properties.
Key points

  1. If the container widget does not have a child it will fill up the the given area on screen.

  2. If it contains child it will have the same width and height as of its child.

  3. It should not be rendered directly on screen without parent widget. We can use Center widget, Padding Widget, Column Widget, Row Widget or Scaffold Widget as parent.

#flutter #exploring flutter widgets #flutter container widget

Elliott  Owen

Elliott Owen

1626913620

Exploring Flutter Widgets || Flutter Scaffold Widget & Its Properties #16

In this video I have discussed about Scaffold widget and its different properties.

It is a widget which implements the basic material design structure for the flutter app.

#flutter #exploring flutter widgets #flutter scaffold widget #its properties