Use loading react placeholders for your components or pages to indicate something may still be loading.
Available in Other JavaScript Frameworks
CoreUI React Placeholder Component is also available for Angular, Bootstrap, and Vue. Explore framework-specific implementations below:
About
Placeholders can be used to enhance the experience of your application. They’re built only with HTML and CSS, meaning you don’t need any JavaScript to create them. You will, however, need some custom JavaScript to toggle their visibility. Their appearance, color, and sizing can be easily customized with our utility classes.
Example
In the example below, we take a typical card component and recreate it with placeholders applied to create a “loading card”. Size and proportions are the same between the two.
import React from 'react'
import {
CButton,
CCard,
CCardBody,
CCardImage,
CCardText,
CCardTitle,
CPlaceholder,
} from '@coreui/react'
export const PlaceholderExample = () => {
return (
<>
<CCard style={{ width: '18rem' }}>
<CCardImage orientation="top" src={'/assets/img/react.jpg'} />
<CCardBody>
<CCardTitle>Card title</CCardTitle>
<CCardText>
Some quick example text to build on the card title and make up the bulk of the card's
content.
</CCardText>
<CButton color="primary" href="#">
Go somewhere
</CButton>
</CCardBody>
</CCard>
<CCard style={{ width: '18rem' }}>
<CCardImage
as="svg"
orientation="top"
width="100%"
height="162"
xmlns="http://www.w3.org/2000/svg"
role="img"
aria-label="Placeholder"
preserveAspectRatio="xMidYMid slice"
focusable="false"
>
<title>Placeholder</title>
<rect width="100%" height="100%" fill="#868e96"></rect>
</CCardImage>
<CCardBody>
<CPlaceholder as={CCardTitle} animation="glow" xs={7}>
<CPlaceholder xs={6} />
</CPlaceholder>
<CPlaceholder as={CCardText} animation="glow">
<CPlaceholder xs={7} />
<CPlaceholder xs={4} />
<CPlaceholder xs={4} />
<CPlaceholder xs={6} />
<CPlaceholder xs={8} />
</CPlaceholder>
<CPlaceholder as={CButton} color="primary" disabled href="#" tabIndex={-1} xs={6} />
</CCardBody>
</CCard>
</>
)
} import React from 'react'
import {
CButton,
CCard,
CCardBody,
CCardImage,
CCardText,
CCardTitle,
CPlaceholder,
} from '@coreui/react'
export const PlaceholderExample = () => {
return (
<>
<CCard style={{ width: '18rem' }}>
<CCardImage orientation="top" src={'/assets/img/react.jpg'} />
<CCardBody>
<CCardTitle>Card title</CCardTitle>
<CCardText>
Some quick example text to build on the card title and make up the bulk of the card's
content.
</CCardText>
<CButton color="primary" href="#">
Go somewhere
</CButton>
</CCardBody>
</CCard>
<CCard style={{ width: '18rem' }}>
<CCardImage
as="svg"
orientation="top"
width="100%"
height="162"
xmlns="http://www.w3.org/2000/svg"
role="img"
aria-label="Placeholder"
preserveAspectRatio="xMidYMid slice"
focusable="false"
>
<title>Placeholder</title>
<rect width="100%" height="100%" fill="#868e96"></rect>
</CCardImage>
<CCardBody>
<CPlaceholder as={CCardTitle} animation="glow" xs={7}>
<CPlaceholder xs={6} />
</CPlaceholder>
<CPlaceholder as={CCardText} animation="glow">
<CPlaceholder xs={7} />
<CPlaceholder xs={4} />
<CPlaceholder xs={4} />
<CPlaceholder xs={6} />
<CPlaceholder xs={8} />
</CPlaceholder>
<CPlaceholder as={CButton} color="primary" disabled href="#" tabIndex={-1} xs={6} />
</CCardBody>
</CCard>
</>
)
} How it works
Create placeholders with the <CPlaceholder> component and a grid column propx (e.g., xs={6}) to set the width. They can replace the text inside an element or be added as a modifier class to an existing component.
We apply additional styling to CButtons via ::before to ensure the height is respected. You may extend this pattern for other situations as needed, or add a within the element to reflect the height when actual text is rendered in its place.
import React from 'react'
import { CButton, CPlaceholder } from '@coreui/react'
export const Placeholder2Example = () => {
return (
<>
<p aria-hidden="true">
<CPlaceholder xs={6} />
</p>
<CPlaceholder
as={CButton}
color="primary"
aria-hidden="true"
disabled
href="#"
tabIndex={-1}
xs={4}
/>
</>
)
} import React from 'react'
import { CButton, CPlaceholder } from '@coreui/react'
export const Placeholder2Example = () => {
return (
<>
<p aria-hidden="true">
<CPlaceholder xs={6} />
</p>
<CPlaceholder
as={CButton}
color="primary"
aria-hidden="true"
disabled
href="#"
tabIndex={-1}
xs={4}
/>
</>
)
} The use of aria-hidden=“true” only indicates that the element should be hidden to
screen readers. The loading behavior of the placeholder depends on how authors
will actually use the placeholder styles, how they plan to update things, etc. Some JavaScript
code may be needed to swap the state of the placeholder and inform AT users of the update.
Width
You can change the width through grid column classes, width utilities, or inline styles.
import React from 'react'
import { CPlaceholder } from '@coreui/react'
export const PlaceholderWidthExample = () => {
return (
<>
<CPlaceholder xs={6} />
<CPlaceholder className="w-75" />
<CPlaceholder style={{ width: '30%' }} />
</>
)
} import React from 'react'
import { CPlaceholder } from '@coreui/react'
export const PlaceholderWidthExample = () => {
return (
<>
<CPlaceholder xs={6} />
<CPlaceholder className="w-75" />
<CPlaceholder style={{ width: '30%' }} />
</>
)
} Color
By default, the <CPlaceholder> uses currentColor. This can be overridden with a custom color or utility class.
import React from 'react'
import { CPlaceholder } from '@coreui/react'
export const PlaceholderColorExample = () => {
return (
<>
<CPlaceholder xs={12} />
<CPlaceholder color="primary" xs={12} />
<CPlaceholder color="secondary" xs={12} />
<CPlaceholder color="success" xs={12} />
<CPlaceholder color="danger" xs={12} />
<CPlaceholder color="warning" xs={12} />
<CPlaceholder color="info" xs={12} />
<CPlaceholder color="light" xs={12} />
<CPlaceholder color="dark" xs={12} />
</>
)
} import React from 'react'
import { CPlaceholder } from '@coreui/react'
export const PlaceholderColorExample = () => {
return (
<>
<CPlaceholder xs={12} />
<CPlaceholder color="primary" xs={12} />
<CPlaceholder color="secondary" xs={12} />
<CPlaceholder color="success" xs={12} />
<CPlaceholder color="danger" xs={12} />
<CPlaceholder color="warning" xs={12} />
<CPlaceholder color="info" xs={12} />
<CPlaceholder color="light" xs={12} />
<CPlaceholder color="dark" xs={12} />
</>
)
} Sizing
The size of <CPlaceholder>s are based on the typographic style of the parent element. Customize them with size prop: lg, sm, or xs.
import React from 'react'
import { CPlaceholder } from '@coreui/react'
export const PlaceholderSizingExample = () => {
return (
<>
<CPlaceholder xs={12} size="lg" />
<CPlaceholder xs={12} />
<CPlaceholder xs={12} size="sm" />
<CPlaceholder xs={12} size="xs" />
</>
)
} import React from 'react'
import { CPlaceholder } from '@coreui/react'
export const PlaceholderSizingExample = () => {
return (
<>
<CPlaceholder xs={12} size="lg" />
<CPlaceholder xs={12} />
<CPlaceholder xs={12} size="sm" />
<CPlaceholder xs={12} size="xs" />
</>
)
} Animation
Animate placeholders with animation="glow" or animation="wave" to better convey the perception of something being actively loaded.
import React from 'react'
import { CPlaceholder } from '@coreui/react'
export const PlaceholderAnimationExample = () => {
return (
<>
<CPlaceholder as="p" animation="glow">
<CPlaceholder xs={12} />
</CPlaceholder>
<CPlaceholder as="p" animation="wave">
<CPlaceholder xs={12} />
</CPlaceholder>
</>
)
} import React from 'react'
import { CPlaceholder } from '@coreui/react'
export const PlaceholderAnimationExample = () => {
return (
<>
<CPlaceholder as="p" animation="glow">
<CPlaceholder xs={12} />
</CPlaceholder>
<CPlaceholder as="p" animation="wave">
<CPlaceholder xs={12} />
</CPlaceholder>
</>
)
} API
Check out the documentation below for a comprehensive guide to all the props you can use with the components mentioned here.