CREATING A REAL-TIME dashboard APP FOR TWITTER USING

REACT.JS

// Erik Wendel, BEKK Consulting // Kim Joar Bekkelund, Elastic 1

Todays Agenda » Presentation an introduction to React » Coding pt 1: getting to know React through small tasks » Coding pt 2: putting together the Twitter Dashboard

2

3

State 4

Back to square one 5

Simple Declarative Interactive data Components 6

Simple

Declarative Interactive data Components

7

Simple Declarative

Interactive data Components 8

Simple Declarative Interactive data

Components 9

A component's responsibility:

Data → DOM 10

Performance?

11

Virtual DOM 1. When something could have changed, re-render everything to a new DOM-representation 2. Diff new output with previous output 3. Update only what has changed

12

render to create output

diff compare output

batch calculate minimal changeset and batch 13

He ain't heavy, he's HTML 14

var ReactDOMElement = { type : string, props : { children : ReactNodeList, className : string, etc. }, key : string | boolean | number | null, ref : string | null };

15

Components 16

var Example = React.createClass({ render: function() { return (Virtual DOM-nodes) } }); React.render(Example(), document.body);

17

Creating virtual dom nodes React.createElement('div', { className: 'ninja' }, 'Hello World!');

Hello World!


18

JSX fully optional (but you'll want it)

19

render: function() { return React.createElement('div', null, 'Hello World!'); }

is equal to render: function() { return
Hello World!
; } 20

WTF? 21

in the build pipeline converting jsx to js

22

var Example = React.createClass({ render: function() { return
Hello World!
} }); React.render(, document.getElementById('main'));

23

var Example = React.createClass({ render: function() { return React.createElement('div'); } }); React.render(, document.getElementById('main'));

24

Why won't this work?! var HelloWorld = React.createClass({ render : function() { return hello world!; } });

25

var HelloWorld = React.createClass({ render : function() { return React.createElement('span', null, 'Hello ')React.createElement('span', null, 'World!'); } });

26

Custom components var RootComponent = React.createClass({ render: function() { return
; } }); Components may consist of native HTML or custom components 27

28

Lets talk about data 29

Props & State props immutable passed down to comp from parent

state changes over time lives in a component

30

Props var Comment = React.createClass({ render: function() { return
{this.props.name} says: {this.props.text}
; } }); React.render(, document.body); 31

var Counter = React.createClass({ getInitialState: function() { return { count: 0 }; }, increment: function(event) { this.setState({ count: this.state.count + 1 }); }, render: function() { return (

You clicked this {count} times.

); } }); React.render(,document.body); 32

One-way data flow data downwards, events upwards

33

Event delegation

34

35

36

Reusability var CommentBox = React.createClass({ render: function() { return

Comments

; } });

37

Lifecycle events: function function function function function ...

componentDidMount() {...} componentWillMount() {...} componentWillUnmount() {...} componentWillUpdate() {...} componentDidUpdate() {...}

38

Lifecycle events var Program = React.createClass({ componentDidMount: function() { this.setFocusOnInputField(); }, componentWillUnmount: function() { this.removeEventListeners(); this.doCleanup(); } } 39

Perform! shouldComponentUpdate: function(nextProps, nextState) { return (whether component should render() or not) }

40

Perform! shouldComponentUpdate: function(nextProps, nextState) { return nextProps.id !== this.props.id; }

41

Flexibility Easy to use React on parts of an app render(, document.body);

42

Server-side rendering var app = express(); app.get('/', function (req, res) { React.renderToString(Timer(), function(markup) { res.send(markup); }); });

43

Flux 44

Summary » challenges best practices

45

Summary » challenges best practices » has awesome performance

46

Summary » challenges best practices » has awesome performance » but main goal = simplify development

47

Summary » challenges best practices » has awesome performance » but main goal = simplify development

48

Summary » challenges best practices » has awesome performance » but main goal = simplify development » small scope - just DOM-manipulation

49

Summary » challenges best practices » has awesome performance » but main goal = simplify development » small scope - just DOM-manipulation » Flux handles the rest

50

Lets get cracking 51

Clone the git repo at

is.gd/javazone15 Ask us if you're new to Git! Follow instructions in the README

52

CREATING A REAL-TIME dashboard APP FOR TWITTER USING ...

When something could have changed, re-render everything to a new DOM-representation. 2.Diff new output with previous output. 3.Update only what has ...

60MB Sizes 2 Downloads 84 Views

Recommend Documents

dash4twitter: A Dashboard for Twitter Analytics - GitHub
framework for future developers so they may ac- cess to a modern interface with the ability to easily integrate more ... From manual examination, it seemed to vary unpredictably with the data and was nat- urally susceptible to ... tive, negative, neu

Creating a Profitable Betting Strategy for Football by Using ... - CiteSeerX
10 required by spread betting companies due to the fact that they are governed by ...... software for fitting the multinomial ordered probit model was not generally.

Realtime Tempo Tracking using Kalman Filtering
Mar 30, 2006 - tempo is as the time interval between beats, referred to as the inter-beat interval or period. With the ... data and raw audio signal for the use of tempo tracking. We will then ...... Meter as mechanism: A neural network model.

Full eBook Information Dashboard Design: Displaying Data for At-a ...
... ( commonly referred to as PDF) is a file format used to present documents in a manner independent of application software, hardware, and operating systems.

Read [PDF] Information Dashboard Design: Displaying Data for At-a ...
The Big Book of Dashboards Visualizing Your Data Using Real World Business Scenarios Steve ... Dashboard Design: Displaying Data for At-a-Glance Monitoring Best Book, Download Best Book ... Publisher : Analytics Press 2013-08-15 q.