# Spoiler

- Page: https://jiguang132.com/resources/mantine/docs/spoiler
- Resource: Mantine Core (https://jiguang132.com/resources/mantine.md)
- All guides: https://jiguang132.com/resources/mantine/docs.md

Install: `npm install @mantine/core@9.7.1 @mantine/hooks@9.7.1`

## Version and compatibility

Pinned Mantine Core 9.7.1 requires React and React DOM `^19.2.0` and matching `@mantine/hooks@9.7.1`, from the installed npm package's peerDependencies. Do not force it into React 18 or another incompatible version. Explain upgrade impact and agree on a plan with the project owner; do not hide conflicts with --force/--legacy-peer-deps. The native Provider enables `theme.respectReducedMotion` and uses `forceColorScheme` for light/dark.

## Use case

Expand content beyond a collapsed maximum height.

## Native props used by this example

These props are extracted from the local typechecked JSX and grouped by their owning native component. This is not an exhaustive prop list; see pinned source signatures and inheritance below.

| Component prop | Explanation |
| --- | --- |
| `Spoiler.maxHeight` | Collapsed content height boundary. |
| `Spoiler.showLabel` | Expand-action label. |
| `Spoiler.hideLabel` | Collapse-action label. |

## Interaction and state checks

Current scenarios: Default. Check actual behavior after selecting supported disabled/error/read-only scenarios; components without those native states do not receive invented universal props. Verify keyboard focus and exits, then connect changed values through the native callback signature.

## Business integration boundary

Demo content/state is local, without server persistence, authorization or fetching. A static display component is not a completed business workflow.

## Host setup

Install pinned @mantine/core and @mantine/hooks, import @mantine/core/styles.css at the entry and use MantineProvider. The example's theme/variant are JGuang-authored host props, not universal native component APIs; forceColorScheme synchronizes the app theme. Native implementation source is a reading reference: use npm exports rather than copying internal engines. This batch covers Core, not dates/charts/forms extension packages. Detailed upstream prose remains English.


## Runnable usage

```tsx
import { useState } from 'react';
import * as M from '@mantine/core';
import '@mantine/core/styles.css';


function ComponentPreview({ variant = 'Default' }: { variant?: string }) {

return <M.Spoiler maxHeight={60} showLabel="Show more" hideLabel="Hide">{Array.from({ length: 6 }, (_, i) => <M.Text key={i}>Design resources for your next project.</M.Text>)}</M.Spoiler>;
}
export default function Example({ variant = 'Default', theme = 'light' }: { variant?: string; theme?: 'light' | 'dark' }) {
return <M.MantineProvider forceColorScheme={theme} theme={{ respectReducedMotion: true }}><ComponentPreview variant={variant} /></M.MantineProvider>;
}

```


## Preview states

Default

The example uses the native Mantine API. For supported input demos, change the local variant to Disabled, Invalid or Read only; these are example labels, not new component props. Keep the documented data, controlled values, stores and compound children when adapting the example.



## Usage

Use `Spoiler` to hide a long section of content.
Set the `maxHeight` prop to control the point at which content will be hidden under the spoiler and the show/hide control appears.
If the content height is less than `maxHeight`, the spoiler will just render children.

`hideLabel` and `showLabel` props are required – they are used as the spoiler toggle button label in the corresponding state.



## Control expanded state

To control the expanded state, use `expanded` and `onExpandedChange` props. Note that the
`expanded` prop does not have any effect on spoiler visuals if the content height
is less than the given `maxHeight`.

```tsx
import { useState } from 'react';
import { Spoiler } from '@mantine/core';

function Demo() {
  const [expanded, setExpanded] = useState(false);

  return (
    <Spoiler
      showLabel="Show more"
      hideLabel="Hide details"
      expanded={expanded}
      onExpandedChange={setExpanded}
    >
      {/* Spoiler content */}
    </Spoiler>
  );
}
```

## Subscribe to expanded state changes

Use `onExpandedChange` to subscribe to expanded state changes:

```tsx
import { Spoiler } from '@mantine/core';

function Demo() {
  return (
    <Spoiler
      showLabel="Show more"
      hideLabel="Hide details"
      onExpandedChange={(expanded) => console.log(expanded)}
    >
      {/* Spoiler content */}
    </Spoiler>
  );
}
```

## Transition duration

Control the transition duration by setting the `transitionDuration` prop (transition-duration CSS property in ms).
To disable animations, set `transitionDuration={0}`:



## Get control ref

```tsx
import { useRef } from 'react';
import { Spoiler } from '@mantine/core';

function Demo() {
  const spoilerControlRef = useRef<HTMLButtonElement>(null);
  return (
    <Spoiler
      controlRef={spoilerControlRef}
      hideLabel="Hide"
      showLabel="Show"
    />
  );
}
```

## Accessibility

The Spoiler component implements proper ARIA attributes for screen reader support:

- Toggle button has `aria-expanded` indicating the expanded/collapsed state
- Content region has `role="region"` and is associated with the button via `aria-controls`
- Keyboard support: Space or Enter key toggles the spoiler when the button is focused

### Best practices for label text

Provide descriptive labels for `showLabel` and `hideLabel` props that clearly indicate the action:

```tsx
// Good - clear, descriptive labels
<Spoiler showLabel="Show full article" hideLabel="Hide article" />
<Spoiler showLabel="Expand details" hideLabel="Collapse details" />

// Avoid vague labels
<Spoiler showLabel="More" hideLabel="Less" />
<Spoiler showLabel="..." hideLabel="..." />
```

### Custom accessibility labels

If your button labels don't clearly describe the action for screen reader users, use the `showAriaLabel` and `hideAriaLabel` props to provide custom ARIA labels:

```tsx
import { Spoiler } from '@mantine/core';

function Demo() {
  return (
    <Spoiler
      showLabel="👁️"
      hideLabel="👁️"
      showAriaLabel="Show discussion comments"
      hideAriaLabel="Hide discussion comments"
    >
      {/* Comments content */}
    </Spoiler>
  );
}
```


## Source-backed parameter reference

Implementation signatures and types are generated from the pinned local source. Optional props, native inherited types, union branches and never exclusions are preserved. A forwardRef implementation's ref is a React reference, not an additional business prop.


```ts
Spoiler(_props)
```



```ts
export type SpoilerStylesNames = 'root' | 'control' | 'content';

export type SpoilerCssVariables = {
  root: '--spoiler-transition-duration';
};

export interface SpoilerProps
  extends BoxProps, StylesApiProps<SpoilerFactory>, ElementProps<'div'> {
  /** Maximum height of visible content in px. When content exceeds this height, the toggle control appears @default 100 */
  maxHeight?: number;

  /** Content displayed in the toggle button when content is collapsed (to expand) */
  showLabel: React.ReactNode;

  /** Content displayed in the toggle button when content is expanded (to collapse) */
  hideLabel: React.ReactNode;

  /** Ref of the toggle button element */
  controlRef?: React.Ref<HTMLButtonElement>;

  /** Initial expanded state in uncontrolled mode. If `true`, content starts expanded. If `false`, content starts collapsed @default false */
  defaultExpanded?: boolean;

  /** Controlled expanded state value */
  expanded?: boolean;

  /** Called when expanded state changes (when spoiler visibility is toggled by the user) */
  onExpandedChange?: (expanded: boolean) => void;

  /** Spoiler reveal transition duration in ms. Set to 0 to disable animation @default 200 */
  transitionDuration?: number;

  /** Accessible label for the toggle button when collapsed. If not set, `showLabel` is used */
  showAriaLabel?: string;

  /** Accessible label for the toggle button when expanded. If not set, `hideLabel` is used */
  hideAriaLabel?: string;
}

export type SpoilerFactory = Factory<{
  props: SpoilerProps;
  ref: HTMLDivElement;
  stylesNames: SpoilerStylesNames;
  vars: SpoilerCssVariables;
}>;

export type Mod = Record<string, any> | string;

export type BoxMod = Mod | Mod[] | BoxMod[];

export interface BoxProps extends MantineStyleProps {
  /** Class added to the root element, if applicable */
  className?: string | undefined;

  /** Inline style added to root component element, can subscribe to theme defined on MantineProvider */
  style?: MantineStyleProp;

  /** CSS variables defined on root component element */
  __vars?: CssVarsProp;

  /** `size` property passed down the HTML element */
  __size?: string;

  /** Breakpoint above which the component is hidden with `display: none` */
  hiddenFrom?: MantineBreakpoint;

  /** Breakpoint below which the component is hidden with `display: none` */
  visibleFrom?: MantineBreakpoint;

  /** Determines whether component should be hidden in light color scheme with `display: none` */
  lightHidden?: boolean;

  /** Determines whether component should be hidden in dark color scheme with `display: none` */
  darkHidden?: boolean;

  /** Element modifiers transformed into `data-` attributes, for example, `{ 'data-size': 'xl' }`, falsy values are removed */
  mod?: BoxMod;
}

export type ElementProps<
  ElementType extends React.ElementType,
  PropsToOmit extends string = never,
> = Omit<React.ComponentProps<ElementType>, 'style' | PropsToOmit>;

export interface CSSProperties extends React.CSSProperties {
  [key: string]: any;
}

type MantineStyle = CSSProperties | ((theme: MantineTheme) => CSSProperties);

export type MantineStyleProp = MantineStyle | MantineStyle[] | MantineStyleProp[] | undefined;

export type CssVariable = `--${string}`;

export type CssVariables<Variable extends string = CssVariable> = Partial<Record<Variable, string>>;

export type CssVars<Variable extends string = CssVariable> =
  | CssVariables<Variable>
  | ((theme: MantineTheme) => CssVariables<Variable>)
  | CssVars<Variable>[];

export type CssVarsProp<Variable extends string = CssVariable> =
  | CssVars<Variable>
  | CssVars<Variable>[];
```


### Native and external types

External types remain defined by React or native dependencies, not manually expanded into guessed props. The installed version's TypeScript definitions are authoritative.


```ts
Factory<{
  props: SpoilerProps;
  ref: HTMLDivElement;
  stylesNames: SpoilerStylesNames;
  vars: SpoilerCssVariables;
}>
MantineStyleProps
React.CSSProperties
MantineTheme
Partial<Record<Variable, string>>
Record<Variable, string>
Variable
MantineBreakpoint
Record<string, any>
StylesApiProps<SpoilerFactory>
React.ElementType
Omit<React.ComponentProps<ElementType>, 'style' | PropsToOmit>
React.ComponentProps<ElementType>
ElementType
PropsToOmit
React.ReactNode
React.Ref<HTMLButtonElement>
HTMLButtonElement
HTMLDivElement
```

---

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