bem-react

bem-react is a module on top of React which joins awesome React with some good BEM-specific features.

Its main goals:

• provide ability to use some kind of bemjson in templates and during usage (instead of ugly jsx or plain js)
• take over manipulation of css classes based on BEM (instead of annoying string concatenation or React.addons.classSet which is also clumsy for BEM-like css classes)

Getting Started

Installation

via npm: npm install bem-react

via bower: bower install bem-react

Building a component

BemReact's component is the same as React's one except you should return bemjson from render method.

Example:

var BemReact = require('bem-react');

var Button = BemReact.createClass({
    getInitialState : function() {
        return {
            focused : this.props.focused
        };
    },

    _onFocus : function() {
        this.setState({ focused : true });
    },

    _onBlur : function() {
        this.setState({ focused : false });
    },

    render : function() {
        return {
            block : 'button',
            tag : 'button',
            mods : {
                size : this.props.size,
                focused : this.state.focused,
                disabled : this.props.disabled
            },
            props : {
                disabled : this.props.disabled,
                onFocus : this._onFocus,
                onBlur : this._onBlur,
                onClick : this.props.onClick
            },
            content : this.props.text
        };
    }
});

Using a component

BemReact.render(
    { block : Button, props : { size : 'xl', disabled : true, text : 'click me' } },
    document.body);
// inserts to body following html:
// <button class="button button_size_xl button_disabled">click me</button>

Composition of components

Let's imagine Dropdown component which is the composition of Button and Popup components:

var Dropdown = BemReact.createClass({
    getInitialState : function() {
        return {
            opened : this.props.opened
        };
    },

    _onButtonClick : function() {
        this.setState({ opened : !this.state.opened });
    },

    render : function() {
        return {
            block : 'dropdown',
            mods : {
                opened : this.state.opened,
                disabled : this.props.disabled
            },
            content : [
                {
                    block : Button,
                    props : {
                        key : 'b',
                        disabled : this.props.disabled,
                        text : 'click me',
                        onClick : this._onButtonClick
                    }
                },
                {
                    block : Popup,
                    mix : [{ block : 'dropdown', elem : 'popup' }],
                    props : {
                        key : 'p',
                        visible : this.state.opened && !this.props.disabled,
                        content : this.props.content
                    }
                }
            ]
        };
    }
});

BEMJSON

There're two kinds of bemjson items.

1. Current rendered component

You're able to use following fields in top-level item returned from render:

• String block block name, required
• String tag html tag, optional, <div> by default
• Object mods modifiers (boolean modifiers are supported as well), optional
• Object props properties (similar to the attrs in the traditional bemjson), optional
• • content inner content, optional

Be careful, you aren't allowed to use mix field there

2. Usage of components

You're able to use following fields:

• Function block link to another block, required
• Object props properties, optional
• Array mix mixed elements, optional

Top-Level API

API is the similar to the original React's API:

createClass(Object specification)

render(Object componentJson, DOMElement container, [Function callback])

renderToString(Object componentJson)

renderToStaticMarkup(Object componentJson)

unmountComponentAtNode(DOMElement container)