57 lines
1.5 KiB
Markdown
57 lines
1.5 KiB
Markdown
---
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title: Collapse
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tags: components,children,state,intermediate
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---
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Renders a component with collapsible content.
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- Use the `React.setState()` hook to create the `isCollapsed` state variable with an initial value of `props.collapsed`.
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- Use an object, `style`, to hold the styles for individual components and their states.
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- Use a `<div>` to wrap both the `<button>` that alters the component's `isCollapsed` state and the content of the component, passed down via `props.children`.
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- Determine the appearance of the content, based on `isCollapsed` and apply the appropriate CSS rules from the `style` object.
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- Finally, update the value of the `aria-expanded` attribute based on `isCollapsed` to make the component accessible.
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```jsx
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function Collapse(props) {
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const [isCollapsed, setIsCollapsed] = React.useState(props.collapsed);
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const style = {
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collapsed: {
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display: 'none'
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},
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expanded: {
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display: 'block'
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},
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buttonStyle: {
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display: 'block',
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width: '100%'
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}
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};
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return (
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<div>
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<button style={style.buttonStyle} onClick={() => setIsCollapsed(!isCollapsed)}>
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{isCollapsed ? 'Show' : 'Hide'} content
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</button>
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<div
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className="collapse-content"
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style={isCollapsed ? style.collapsed : style.expanded}
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aria-expanded={isCollapsed}
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>
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{props.children}
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</div>
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</div>
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);
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}
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```
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```jsx
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ReactDOM.render(
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<Collapse>
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<h1>This is a collapse</h1>
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<p>Hello world!</p>
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</Collapse>,
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document.getElementById('root')
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);
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```
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