useWheel

This hook provides a way to implement wheel event in any HTMLElement.

Arguments

callback [ function ]

First argument is a callback function with wheel event object as its first argument which is called on every wheel event.

Here are the properties of an event object argument of a callback function:

Property	Description
target	Current target element to which the wheel event bound to.
deltaX	Wheel delta amount along horizontal axis.
deltaY	Wheel delta amount along vertical axis.
movementX	Amount of movement in x-axis. Always starts from 0 while wheeling.
movementY	Amount of movement in y-axis. Always starts from 0 while wheeling.
offsetX	Amount of movement with offset in x-axis. It saves the previous movement and wheel starts from previous position.
offsetY	Amount of movement with offset in y-axis. It saves the previous movement and wheel starts from previous position.
velocityX	Velocity along horizontal wheel direction.
velocityY	Velocity along vertical wheel direction.
directionX	Indicates the current horizontal wheel direction. For positive +1, for negative -1 and for not wheeling 0.
directionY	Indicates the current vertical wheel direction. For positive +1, for negative -1 and for not wheeling 0.

Returns

It returns a function which is spread on any HTMLELement.

Define a bind function:

const bind = useWheel((event) => doSomething(event));

Apply it on a HTMLELement:

<div {...bind()} style={{ width: 100, height: 100, backgroundColor: 'red' }} />

Example

In the below example, useWheel hook is used to capture wheel event on HTMLElement.

import { useAnimatedValue, useWheel, AnimatedBlock } from 'react-ui-animate';

export default function () {
  const left = useAnimatedValue(0);

  const bind = useWheel(function ({ movementX, isWheeling }) {
    left.value = isWheeling ? movementX : 0;
  });

  return (
    <AnimatedBlock
      {...bind()} // bind here
      style={{
        width: 100,
        height: 100,
        backgroundColor: '#3399ff',
        position: 'absolute',
        left: left.value,
        top: 0,
      }}
    />
  );
}