Merge pull request #47 from phaniteja1/collapse

change collapse component to hooks implementation
This commit is contained in:
Angelos Chalaris
2019-02-12 20:25:06 +02:00
committed by GitHub

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@ -2,55 +2,46 @@
Renders a component with collapsible content. Renders a component with collapsible content.
Use the value of the `collapsed` prop to determine the initial state of the content (collapsed/expanded). Use the `React.setState()` hook to create the `isCollapsed` state variable with an initial value of `props.collapsed`.
Set the `state` of the component to the value of the `collapsed` prop (cast to a boolean value) and bind the `toggleCollapse` method to the component's context.
Use an object, `style`, to hold the styles for individual components and their states. Use an object, `style`, to hold the styles for individual components and their states.
Create a method, `toggleCollapse`, which uses `Component.prototype.setState` to change the component's `state` from collapsed to expanded and vice versa. 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`.
In the `render()` method, use a `<div>` to wrap both the `<button>` that alters the component's `state` and the content of the component, passed down via `props.children`. Determine the appearance of the content, based on `isCollapsed` and apply the appropriate CSS rules from the `style` object.
Determine the appearance of the content, based on `state.collapsed` and apply the appropriate CSS rules from the `style` object. Finally, update the value of the `aria-expanded` attribute based on `isCollapsed` to make the component accessible.
Finally, update the value of the `aria-expanded` attribute based on `state.collapsed` to make the component accessible.
```jsx ```jsx
class Collapse extends React.Component { function Collapse(props) {
constructor(props) { const [isCollapsed, setIsCollapsed] = React.useState(props.collapsed);
super(props);
this.state = { const style = {
collapsed: !!props.collapsed collapsed: {
}; display: "none"
this.style = { },
collapsed: { expanded: {
display: 'none' display: "block"
}, },
expanded: { buttonStyle: {
display: 'block' display: "block",
}, width: "100%"
buttonStyle: { }
display: 'block', };
width: '100%'
} return (
}; <div>
this.toggleCollapse = this.toggleCollapse.bind(this); <button
} style={style.buttonStyle}
onClick={() => setIsCollapsed(!isCollapsed)}
toggleCollapse() { >
this.setState(state => ({ collapsed: !state.collapsed })); {isCollapsed ? "Show" : "Hide"} content
} </button>
<div
render() { className="collapse-content"
return ( style={isCollapsed ? style.collapsed : style.expanded}
<div> aria-expanded={isCollapsed}
<button style={this.style.buttonStyle} onClick={this.toggleCollapse}> >
{this.state.collapsed ? 'Show' : 'Hide'} content {props.children}
</button>
<div
style= {this.state.collapsed ? this.style.collapsed : this.style.expanded}
aria-expanded = {this.state.collapsed}
>
{this.props.children}
</div>
</div> </div>
); </div>
} );
} }
``` ```