How to pass Styled-Component theme variables to Components? - reactjs

Question

Within my React+StyledComponent app, I have a theme file like so:
theme.js:
const colors = {
blacks: [
'#14161B',
'#2E2E34',
'#3E3E43',
],
};
const theme = {
colors,
};
export default theme;
Currently, I can easily use these colors to style my components like so:
const MyStyledContainer = styled.div`
background-color: ${(props) => props.theme.colors.blacks[1]};
`;
The problem is, how do I pass blacks[1] to a Component as the prop of the color to use like so:
<Text color="black[1]">Hello</Text>
Where Text.js is:
const StyledSpan = styled.span`
color: ${(props) => props.theme.colors[props.color]};
`;
const Text = ({
color,
}) => {
return (
<StyledSpan
color={color}
>
{text}
</StyledSpan>
);
};
Text.propTypes = {
color: PropTypes.string,
};
export default Text;
Currently the above is silently failing and rending the following in the DOM:
<span class="sc-brqgn" color="blacks[1]">Hello</span>
Any ideas on how I can get this to work? Thank you

Answer 1

EDIT: Updated to use styled-components withTheme HOC
New answer
You could wrap the component rendering <Text> in the higher order component (HOC) withTheme provided by styled-components. This enables you to use the theme given to the <ThemeProvider> directly in the React component.
Example (based on the styled-components docs):
import React from 'react'
import { withTheme } from 'styled-components'
import Text from './Text.js'
class MyComponent extends React.Component {
render() {
<Text color={this.props.theme.colors.blacks[1]} />;
}
}
export default withTheme(MyComponent)
Then you could do
const MyStyledContainer = styled.div`
background-color: ${(props) => props.color};
`;
Old answer
You could import the theme where you render and pass <Text color={theme.blacks[1]} />.
import theme from './theme.js'
...
<Text color={theme.colors.blacks[1]} />
Then you could do
const MyStyledContainer = styled.div`
background-color: ${(props) => props.color};
`;

Answer 2

You can use defaultProps
import PropTypes from 'prop-types'
MyStyledContainer.defaultProps = { theme }

Answer 3

App.js
App gets theme and passes color to Text
import React, { Component } from 'react'
import styled from 'styled-components'
const Text = styled.div`
color: ${props => props.color || 'inherit'}
`
class App extends Component {
render() {
const { theme } = this.props
return (
<Text color={theme.colors.black[1]} />
)
}
}
export default App
Root.js
Root component passes theme to entire application.
import React, { Component } from 'react'
import { ThemeProvider } from 'styled-components'
import theme from './theme'
import App from './App'
class Root extends Component {
render() {
return (
<ThemeProvider theme={theme}>
<App />
</ThemeProvider>
)
}
}
export default Root

Answer 4

If you're using functional components in React and v4.x and higher styled-components, you need to leverage useContext and styled-components' ThemeContext. Together, these allow you to use your theme settings inside of components that aren't styled-components.
import { useContext } from 'react'
import { ThemeContext } from 'styled-components'
export default function MyComponent() {
// place ThemeContext into a context that is scoped to just this component
const themeProps = useContext(ThemeContext)
return(
<>
{/* Example here is a wrapper component that needs sizing params */}
{/* We access the context and all of our theme props are attached to it */}
<Wrapper maxWidth={ themeProps.maxWidth }>
</Wrapper>
</>
)
}
Further reading in the styled-components docs: https://styled-components.com/docs/advanced#via-usecontext-react-hook