I recently started using Gatsby for building my websites, previously I relied just on plain html and css, so I may be missing something really basic here...
I am trying to style a custom header component that looks like this
import React from "react"
import MWidth from "./m-width"
import logo from "../resources/images/logo.png"
function Header() {
return (
<>
<MWidth>
<div>
<img src={`${logo}`}></img>
</div>
</MWidth>
</>
)
}
export default Header
after importing it inside the layout component I tried styling it with styled-components like so
const PageHeader = styled(Header)`
background-color: #f0f;
`
but nothing changed.
I saw this approach being used with the Link component, but maybe it's defined in another way. Am I missing something or is it just a Gatsby error?
My Layout.js file looks like this
import React from "react"
import styled from "styled-components"
import Header from "./header"
import Content from "./content"
import Footer from "./footer"
import "./common.css"
const PageHeader = styled(Header)`
background-color: #f0f;
`
function Layout(props) {
return (
<>
<PageHeader />
<Content>{props.children}</Content>
<Footer />
</>
)
}
export default Layout
Let me know if you need more information. Any help would be appreciated.
Thanks 😉
Edit:
Turns out that in order for this to work you have to attach a class name to the element you want to style passing it as a prop.So as ksav suggested I added props into the Header function declaration and className={props.className} to a wrapper div. Now it looks like this
function Header(props) {
return (
<div className={props.className}>
<MWidth>
<div>
<img src={`${logo}`}></img>
</div>
</MWidth>
</div>
)
}
which essentially is the same thing as the one he posted below. And this solved the problem.
Thank you 😄
Styling any component
The styled method works perfectly on all of your own or any third-party component, as long as they attach the passed className prop to a DOM element.
function Header({className}) {
return (
<div className={className}>
<MWidth>
<div>
<img src={`${logo}`}></img>
</div>
</MWidth>
</div>
)
}
Related
My biggest problem is that I have not been able to get my react app to display since the first week of the course's assignment. I am at the end of the second week, and have been dealing with this second assignment for several weeks since the course is online through coursera.org.
I have gone over the assignment from week one and watched the videos over and over again, and made many revisions after googling a lot of the answers to the correct code. I have also gone through the resources of week one that the course offers.
I posted numerous times on week one's discussion board and follow the suggestions given. I still was not able to get the react app to display, so I moved one the week 2 assignment, and continued working on it.
After more than two weeks of a lot of trial and error and following the error prompts from the visual studio which is the one I am using for this course, I finally started to get some input on what errors I needed to fix on the editor through the cmd window. Every time I make corrections and run yarn start again, the app started to let me know what I needed to fix on the code. The following image is the last error that I got. Any suggestions are greatly appreciated.
This is the code of the functional component that is giving me the error.
import React from 'react';
import { Card, CardImg, CardImgOverlay, CardTitle, Breadcrumb, BreadcrumbItem } from 'reactstrap';
import {Link } from 'react-router-dom';
import { DishDetail } from 'reactstrap';
import { Menu } from 'reactstrap';
function RenderMenuItem ({dish, onClick}) {
return(
<card>
<Link to={`/menu/${dish.id}`} >
<cardImg width = "100%" src ={dish.image} alt={dish.name} />
<cardImgOverlay>
<cardTitle>
{dish.name}
</cardTitle>
</cardImgOverlay>
</Link>
</card>
);
}
function Millie (props) {
const menu = props.dishes.map((dish)=>{
return(
<div key={dish.id} className="col-12 col-md-5 m-1">
<RenderMenuItem dish={dish} />
</div>
);
});
}
return(
<div className="container">
<div className="row">
<Breadcrumb>
<BreadcrumbItem><Link to="/home">Home</Link></BreadcrumbItem>
<BreadcrumbItem active>Menu</BreadcrumbItem>
</Breadcrumb>
<div className="col-12">
<h3>Menu</h3>
<hr />
</div>
</div>
<div className="row">
{menu}
</div>
</div>
);
export default function Menu(){
}
Almost all if code has been provided by professor.
Error page from React App
Any suggestions are greatly appreciated!
ty
Mildred
As the error says, you're trying to declare something called "Menu" when something called "Menu" already exists.
import { Menu } from 'reactstrap';
export default function Menu(){
}
Either rename the Menu function component or rename the imported one:
// either rename this on import
import { Menu as ReactStrapMenu } from 'reactstrap';
// or call your Menu component something else
export default function MyMenu () {
}
As Chris points out in the comment below, it seems likely that you don't intend to export the empty Menu function at the bottom at all, and perhaps meant to export your Millie component? In that case, just replace the default export at the end with:
export default Millie;
Or export it in the same place you're defining it:
export default function Millie (props) {
const menu = props.dishes.map((dish)=>{
// etc.
}
Mildred! Nice that you're practicing, courses are awesome to learn the basics.
As described in the error you provided, "Menu" is declared twice. If you check the code snippet, you can see that you imported "Menu" from a library, but also declared a function called "Menu".
That is where that error comes from. Just change your default function to any other name, such as "MyMenu"
I am trying to pass a locally stored image name to a component via props. The problem is
<img src={require(`../assets/img/${iconName}.svg`)} />
is not working. I have bootstrapped the project using create-react-app. The component looks like this:
import React from 'react';
import best from '../../assets/img/best.svg';
import cashback from '../../assets/img/cashback.svg';
import shopping from '../../assets/img/shopping.svg';
const Card = ({iconName}) => {
return (
<>
<img alt="icon" src={require(`../assets/img/${iconName}.svg`)} />
</>
);
};
export default Card;
SVGs are failing to load. Even if I write something like:
<img src={require('../assets/img/best.svg')} />
<img src={`${iconName}`} />
it doesn't work. Can this be an issue with webpack loader in CRA?
Because those are SVGs, I imagine, there's a static number of images you might want to display.
At this point you might need to import them all in the beginning. Depending on the tools that you're using around react the dynamic loading of data may or may not work. Your approach definitely would not work for instance with Next.JS (a framework around react).
so I would suggest just loading them all, putting into a map and using that instead of the dynamic require.
import React from 'react';
import best from '../../assets/img/best.svg';
import cashback from '../../assets/img/cashback.svg';
import shopping from '../../assets/img/shopping.svg';
const icons = Object.freeze({best, cashback, shopping});
const Card = ({iconName}) => (<img alt="icon" src={icons[iconName]} />);
export default Card;
I'm trying to build a portfolio website in React ,i'm very new to React (about 3 days), and i have imported some code for the website nav bar and declared it in the code but it doesn't show up on the website and vscode says that the value was not declared. How do i fix this?
I've tried turning the code into a component and rearranging the code but i still get the same result.
App.js - main code
import React from 'react';
import './App.css';
import navBar from './navBar/navBar';
function App() {
return (
<div className="app">
//navBar that won't show up
<navBar />
<div className="landingPage"></div>
<div className="projectPage"></div>
<div className="aboutPage"></div>
<div className="footer"></div>
</div>
)
}
export default App;
Code for the navBar
import React from "react";
import "./navBar.css";
function navBar() {
return (
<div>
<h1>NAVBAR PLACEHOLDER</h1>
</div>
)
}
export default navBar;
Your question title is little bit wierd. You have fixed the value error in your code. But you still have error with the component:
//navBar that won't show up
<navBar />
In react custom built components name should always start with capital letter. So do this:
import NavBar from './navBar/navBar';
// -- ^^ you can name it anything as it's default import
<NavBar />
I'm using Next.js, React, Styled JSX, and Postcss if that matters. I need to style an imported component for a specific page. Since the stylesheets are created for a specific component at the time of render, I figured I could just put the custom styles for the component in with the page specific resources and pass them in. But I'm getting the following error:
Expected a template literal or String literal as the child of the JSX Style tag (eg: <style jsx>{`some css`}</style>), but got MemberExpression
I have two functional renders in two separate directories and files, one a page and the other a component:
src/pages/mypage/
index.js
styles.css
myComponentStyles.css
src/components/MyComponent
index.js
styles.css
Keeping in mind that file/directory referencing is not mirrored from my environment because it's not the problem, here's my code:
src/pages/mypage/index.js
import MyComponent from '../../components/MyComponent'
import styles from './styles.css'
import MyComponentStyles from './myComponentSyles'
const MyPage = () => {
return (
<div className="my-page-container">
<style jsx>{styles}</style>
<MyComponent styles={MyComponentStyles} />
</div>
)
}
export default MyPage
src/components/MyComponent/index.js
import styles from './styles.css'
const myComponent = props => {
return (
<>
<style jsx>{styles}</style>
<style jsx>{props.styles}</style>
<div className="my-component-main-container">MyComponent</div>
</>
)
}
export default MyComponent
How would I allow MyComponent to receive a stylesheet generated by another component?
Although this is not a direct solution to the problem, Styled JSX has a :global() pseudo selector that accomplishes the end goal of styling a component that is outside the scope of the current component. A working example for the given code is:
src/pages/mypage/styles.css
.my-page-container :global(.my-component-main-container){
color: white;
}
Here is what the Next.js documentation says for the :global() pseudo selector:
One-off global selectors
Sometimes it's useful to skip selectors scoping. In order to get a
one-off global selector we support :global(), inspired by css-modules.
This is very useful in order to, for example, generate a global class
that you can pass to 3rd-party components. For example, to style
react-select which supports passing a custom class via
optionClassName:
import Select from 'react-select'
export default () => (
<div>
<Select optionClassName="react-select" />
<style jsx>{`
/* "div" will be prefixed, but ".react-select" won't */
div :global(.react-select) {
color: red
}
`}</style>
</div> )
First, I would like to dynamic title tab.
Title tab change by every single page's <h2> Something</h2>
So I tried to make <h2 id="name">something</h2> I made title tab page as one single html page. and each of different javascript page has own <h2>
I tried to use var something =document.getElementById("name") then document.title=something like this.
But this main file can't get elements which is in external file.
Is there anyway I can make dynamic title tab?
no jquery.
Using ReactJS
You can create a component just for the title. Have that component accept a prop called "title" and then display that title.
Title Component: your title component can be a functional component
import React from 'react';
export default (props) => {
return (
<div className="your class names for this title">
<h2>{this.props.title}</h2>
</div>
)
}
This is perfectly fine functional component syntax. Just save the file as "Title.js". And you can import it in your parent component like so:
import Title from "./path/of/Title/Title";
And that will work just fine. If you are not comfortable with that syntax you can rewrite it like this:
const Title = (props) => (
<div className="your class names for this title">
<h2>{this.props.title}</h2>
</div>
);
This is perfectly valid as well. Next, let's discuss the parent component. Your parent component is your page. So, let's call this component "Home" just for this example.
Home Component: a class component (assuming it will have state but it does not have to be a class component)
import React, { Component } from 'react';
//import Title component
import Title from "./path/of/Title/Title"; //note: your component should be in a directory that has the same name as the component
export default class Home extends Component {
render() {
return (
<div>
<Title title="insert title here" />
<div>
Rest of your home component
</div>
</div>
)
}
}
That's it. You have a dynamic title. Now, let's say you want to pass a variable to the prop "title" instead of always hard coding a string. Well, you can update this line:
<Title title="insert title here" />
to this:
<Title title={nameOfVariable} />
And if that variable is coming from your state you can do this:
<Title title={this.state.nameofvariable} />
You can always destructure your state and do this instead:
render(){
const { nameofvariable } = this.state;
return (
<div>
<Title title={nameofvariable} />
<div>
Rest of your home component
</div>
</div>
);
}
That's all you need. Hope that helps. Good luck.