React - 如何使用样式组件向组件添加新样式

Question

I am using Styled components. I have two components Navbar and Lessons

Navbar.jsx

import React, {Fragment} from 'react';
import n from './Navbar.module.css';
import logo from '../../backgrounds/myLogo2.png'
import {NavLink} from 'react-router-dom';
import styled from "styled-components";

export const NavBarPageLogoDivContainer = styled.div`
 &.LogoDivContainer {
    flex: 1;
  }
`;

export const Navbar = (props) => {
    return (
        <Fragment>
            <div>
                <header>
                    <NavBarPageLogoDivContainer className={"LogoDivContainer"}>
                        <NavLink className={n.logo} to={'/content'}>
                            <img style={{margin: 'auto', marginTop: "0", width: "150px", maxWidth: "100%"}} src={logo}
                                 alt="logo"/>
                        </NavLink>
                    </NavBarPageLogoDivContainer>
                </header>
            </div>
        </Fragment>
    );
}

Lessons.jsx

import React from 'react';
import {Navbar, NavBarPageLogoDivContainer} from "../../../Navbar/Navbar";
import styled from "styled-components";

export class Lessons extends React.Component {
    render() {
        return (
            <>
                <Navbar />
            </>
        );
    }
}

I deliberately removed the rest of the jsx from these components to make the code easier to read. Please pay attention to the "NavBarPageLogoDivContainer" in Navbar.jsx, where I specified the value "flex: 1". When I imported the Navbar into the Lesson component I want to add new styles for the "NavBarPageLogoDivContainer", for example background, border, padding. how can I do it?

Answer 1

You can use styled as a function:

const myNewlyStyledComponent = styled(NavBarPageLogoDivContainer)`
background-color: "red";
height: 0%;
`

and then use the myNewlyStyledComponent in the rendering part.

To use your new component in the snippet you should change the code:

Navbar.jsx

import React, {Fragment} from 'react';
import n from './Navbar.module.css';
import logo from '../../backgrounds/myLogo2.png'
import {NavLink} from 'react-router-dom';
import styled from "styled-components";

export const NavBarPageLogoDivContainer = styled.div`
 &.LogoDivContainer {
    flex: 1;
  }
`;

export const Navbar = ({CustomNavBarLogoDivContainer}) => {
    const InjectedContainer = CustomNavBarLogoDivContainer ?? NavBarPageLogoDivContainer

    return (
        <Fragment>
            <div>
                <header>
                    <InjectedContainer className={"LogoDivContainer"}>
                        <NavLink className={n.logo} to={'/content'}>
                            <img style={{margin: 'auto', marginTop: "0", width: "150px", maxWidth: "100%"}} src={logo}
                                 alt="logo"/>
                        </NavLink>
                    </InjectedContainer>
                </header>
            </div>
        </Fragment>
    );
}

now you can parametrize the navbar with the enhanced component:

Lesson.jsx

import React from 'react';
import {Navbar, NavBarPageLogoDivContainer} from "../../../Navbar/Navbar";
import styled from "styled-components";

const myNewlyStyledComponent = styled(NavBarPageLogoDivContainer)`
background-color: "red";
`

export class Lessons extends React.Component {
    render() {
        return (
            <>
                <Navbar 
                     CustonNavBarLogoDivContainer={myNewlyStyledComponent}
                />
            </>
        );
    }
}

Here in react docs you can read briefly about composition