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    4.2.8 • Public • Published

    React Modifier

    ReactModifier is a tool that can help you to customize app. Main idea - many themes, one component.


    npm npm npm npm

    This package can:

    • Mix modifiers
    • Modify component head to position it
    • Modify whole component to apply a theme

    What's the problem?

    How many component's visual style can you modify without changing its code? The value is low I bet.

    An example of typical situation

    const TestC = (
        <div classname="test">
            <div className="test__block">
                <span className="test__text">Text</span>
    const App = (
        <div classname="app">
            <TestC />

    Can't add theme or change position. Obviously you can't reuse that component. Cause if you're going to position it, you position it everywhere.

    Can we solve the problem? Actually we can. There is 2 ways:

    1. Create wrapper with class, that modifies nested elements
    2. Create component, that receives modifiers props, and returns modified version.

    Solved example:

    // first method
    const App = (
        <div classname="app">
            {/* unwanted structure */} 
            <div className="app__testc">
                <TestC />
    // second method
    const mod = { className: "app__testc" };
    const App = (
        {/* all good */} 
        <div classname="app">
            <TestC mod={mod} />

    This package using second way.


    📦 To download this package from npm paste this command in a terminal

    npm install react-modifier

    How to use

    First of all you have to import the library.

    import * as RM from "react-modifier";
    // OR you can import individual functions and interfaces
    // import { IModifiableProps, IModifiableTheme, IModifier, createMod, mixMod, modElement} from "react-modifier";

    Then you can create customizable functional or class components

    Functional component example

    // define theme & props interfaces
    export interface FlexAppTheme extends IModifiableTheme {
        textMod: IModifier;
    export interface IFlexAppProps extends IModifiableProps<FlexAppTheme> {
        text: string;
    export const FlexAppF: FunctionComponent<IFlexAppProps> = (props: IFlexAppProps) => {
        const { text, theme, mod } = props;
        const headMod = getHeadModByProps(props);
        return modElement((
            <div className="app">
                    <span className="app__text">
                ), theme.textMod)}
        ), headMod);
    // theme instances
    const defaultTheme: FlexAppTheme = {
        head: createMod(""),
        textMod: createMod("")
    const darkTheme: FlexAppTheme = {
        head: createMod("app_dark"),
        textMod: createMod("app__text_dark")
    // all themes
    export const flexAppThemes = {
        dark: darkTheme,
        default: defaultTheme

    Class component

    Just import IModifiableComponent class.

    export class FlexApp extends IModifiableComponent<FlexAppTheme, IFlexAppProps> {
        constructor(props: IFlexAppProps) {
        renderThemed() {
            <div className="app">
                    <span className="app__text">
                ), this.theme.textMod)}
    // also it's possible to pass third type or interface, that describes State
    // <FlexAppTheme, IFlexAppProps, IFlexAppState>

    Okay, now we can use new component. A Theme prop is required, mod is optional, you always can define default theme in component.

    FlexAppF text="It actually works" mod={createMod("root__app")} theme={flexAppThemes.dark}></FlexAppF>

    The result will be

        <div class="app root__app app_dark">
            <span class="app__text app__text_dark">It actually works</span>


    Let's take a look how does it work

    Modifier is just an interface, that haves className and id properties;

    interface IModifier {
        className: string;
        id: string;
        // if you want to modify more props, fork my github repo

    createMod function wraps your args to new IModifier obj

    // createMod(className?, id?);
    createMod("mod_class", "mod-el");

    mixModifier function combining all classNames to one and takes first id

    mixModifiers(mod, mod2, mod3...) => IModifier;

    modElement function applies mod on provided element and

    returns modified version

    modElement(element: ReactElement, mod: IModifier): ReactElement;

    IModifiableProps is an interface that haves theme and head mod

    interface IModifiableProps<T> {
        theme: T; // head && body modifiers
        mod?: IModifier; // component head modifier
        inputMod: IModifier; // custom mod
    // extend that interface to add other props

    IModifiableTheme contains head mod

    interface IModifiableTheme {
        head: IModifier;
    // extend that interface to add other customizable parts

    IModifiableComponent class has constructor with modifer props & renderThemedMethod

    // pass your own Theme & Props interface realization
    class IModifiableComponent<Theme: IModifiableTheme, Props: IModifiableProps, State?> extends React.Component {
        renderThemed(): ReactElement; 
        // Return elements here, but don't modify first element! 
        // It's already doing render method. 

    Enjoy this package


    npm i react-modifier

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    GNU General Public License, version 2

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    232 kB

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    Last publish


    • kostayne