@react-hook/throttle/README.md

A React hook for throttling setState and other callbacks

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  <h1 align="center">
    useThrottle()
  </h1>
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<pre align="center">npm i @react-hook/throttle</pre>
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A React hook for performantly throttling `setState` and other callbacks.

## Quick Start

```jsx harmony
import {useThrottle, useThrottleCallback} from '@react-hook/throttle'

const Component = (props) => {
  // at a basic level, used just like useState
  const [value, setValue] = useThrottle('initialValue')
}

const useMyCallback = (initialState, wait, leading) => {
  // this is the same code useThrottle() uses to throttle setState
  const [state, setState] = useState(initialState)
  return [state, useThrottleCallback(setState, wait, leading)]
}
```

## API

### useThrottle(initialState, fps?, leading?)

A hook that acts just like `React.useState`, but with a `setState` function
that is only invoked at most X frames per second. A trailing call is guaranteed,
but you may opt-in to calling on the leading edge, as well.

```ts
export const useThrottle = <State>(
  initialState: State | (() => State),
  fps?: number,
  leading?: boolean
): [State, Dispatch<SetStateAction<State>>]
```

#### Arguments

| Property     | Type                    | Default | Description                                                                                                                |
| ------------ | ----------------------- | ------- | -------------------------------------------------------------------------------------------------------------------------- |
| initialState | `State | (() => State)` |         | The initial state provided to `React.useState()`                                                                           |
| fps          | `number`                | `30`    | Defines the rate in frames per second with which `setState` is invoked with new state                                      |
| leading      | `boolean`               | `false` | Calls `setState` on the leading edge (right away). When `false`, `setState` will not be called until the next frame is due |

#### Returns `[state, setState]`

| Variable | Type                              | Description                     |
| -------- | --------------------------------- | ------------------------------- |
| state    | `State`                           | The current value in state      |
| setState | `Dispatch<SetStateAction<State>>` | A throttled `setState` callback |

---

### useThrottleCallback(callback, fps?, leading?)

A hook that invokes its callback at most X frames per second. A trailing call is guaranteed,
but you may opt-in to calling on the leading edge, as well.

```ts
export const useThrottleCallback = <Callback extends (...args: any[]) => void>(
  callback: Callback,
  fps = 30,
  leading = false
): Callback
```

#### Arguments

| Property | Type                                | Default | Description                                                                                                                                                                          |
| -------- | ----------------------------------- | ------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| callback | `((...args: CallbackArgs) => void)` |         | This is the callback you want to throttle. You need to wrap closures/unstable callbacks in `useCallback()` so that they are stable, otherwise throttling will break between renders. |
| fps      | `number`                            | `30`    | Defines the rate in frames per second with which `setState` is invoked with new state                                                                                                |
| leading  | `boolean`                           | `false` | Calls `setState` on the leading edge (right away). When `false`, `setState` will not be called until the next frame is due                                                           |

#### Returns `throttledCallback`

| Variable          | Type                                | Description                          |
| ----------------- | ----------------------------------- | ------------------------------------ |
| throttledCallback | `((...args: CallbackArgs) => void)` | A throttled version of your callback |

## LICENSE

MIT