use-mouse-drag
v1.0.2
Published
A react hook for creating interaction by dragging the mouse e.g., moving elements and drawing boxes
Downloads
89
Maintainers
Readme
use-mouse-drag
A react hook for creating interaction by dragging the mouse e.g., moving elements and drawing boxes
Install
npm install --save use-mouse-drag
Basic Usage
const { mousePosition, dragging } = useMouseDrag(element, constraints)
The mousePosition variable changes whenever the mouse moves. The object contains a start attribute and an end attribute indicating the location of the mouse at the start and the end of dragging. The dragging variable indicates whether or not the mouse is currently down. The mousePosition.start
is an undefined value when not being dragged, use mousePosition.end
to get current mousePosition.
Both the parameters passed into the hook are optional, The element
parameter is the element that will listen for drags and will default to the entire page. The constraints
parameter is an array of functions, the function gets passed a mousePosition and if any of the functions are false a drag will not begin.
See the Example below to see how it all fits together.
Example
import React, { useRef, useCallback, useState, useEffect } from 'react'
import { useMouseDrag, useChange } from 'use-mouse-drag'
const App = () => {
const [ allowDragging, setAllowDragging ] = useState(true);
const canvasRef = useRef();
const allowDraggingRef = useRef(allowDragging);
const { mousePosition, dragging } = useMouseDrag(canvasRef.current, [
mousePosition => allowDraggingRef.current
]);
useEffect(() => {
allowDraggingRef.current = allowDragging;
}, [ allowDragging ]);
useChange(() => {
// Drag ended
if (!dragging) {
alert('Dragged: ' + JSON.stringify(mousePosition))
}
}, [ dragging ]);
return (
<React.Fragment>
<div ref={canvasRef} className="canvas"
style={
{ opacity: allowDragging ? 1: 0.4 }
}>
</div>
<div>Dragging: { dragging.toString() }</div>
<div>Position: { JSON.stringify(mousePosition) }</div>
<button onClick={() => setAllowDragging(!allowDragging)}>
Turn dragging { allowDragging ? 'Off' : 'On' }
</button>
</React.Fragment>
)
}
export default App
License
MIT © jackdeadman
This hook is created using create-react-hook.