react-brush 🚧

Render an svg with a highlightable area.

Installation

yarn add react-brush

Basic Usage

The default export of react-brush is a component.

import ReactBrush from 'react-brush';

// ...
  <ReactBrush height={200} width={500} />
// ...

This will render an svg with a brush overlay that is enabled when the user presses and holds mouse button 0 for a short time ( >= 300ms) or clicks, holds and begins to drag. The selected region will be displayed while the brush is in progress. Callbacks can be registered to handle the start, stop and change of a brush action.

<ReactBrush
  height={200}
  width={500}
  onBrushStart={handleBrushStart}
  onBrushEnd={handleBrushEnd}
  onBrushChange={handleBrushChange}
/>

The callbacks will receive a single object parameter with the following type:

{
  x: number,       // x and y represent the top left corner of the selected region relative
  y: number,       // to the origin of the svg's viewable area

  width: number,   // the width and height of selected region
  height: number,  
}

react-brush also exports a BrushedArea component that can be used to customize the selected area. Pass it as the prop brushedArea to the ReactBrush component.

<ReactBrush
  height={200}
  width={500}
  brushedArea={<BrushedArea fullHeight />}
/>

The brushedArea prop can alternatively be a render callback that will be passed a single object parameter with the shape { brush: Object, container: Object }. The brush property is an object of the same type as that passed to the brush callbacks. The container property is an object with the shape { top: number, bottom: number, left: number, right: number } describing the position of the ReactBrush container in the document.

<ReactBrush
  height={200}
  width={500}
  brushedArea={({ container, brush }) => {
    /* do something awesome */
  }}
/>

react-brush only provides a brushed area during a brush and the callbacks to let you know what was brushed. How the selection should affect your elements is up to you to implement.

react-brush composes well with other interactive graphical elements because it gets out of the way when a brush isn't active and won't interfere with other mouse events.

See the demo for some working examples.

API:

<ReactBrush> Props

Property	Type	Required	Default	Description
width	number	yes	undefined	The width of the brush container
height	number	yes	undefined	The height of the brush container
onBrushStart	function	no	undefined	The callback to use if any when a brush is started (the user presses mouse button 0)
onBrushStop	function	no	undefined	The callback to use if any when a brush is stopped (the user releases mouse button 0)
onBrushChange	function	no	undefined	The callback to use if any when a brush is changed (the user drags while holding down mouse button 0)
brushedArea	function or element	no	<BrushedArea />	The element or render callback to use to render the brushed area
tag	string ("svg" or "g")	no	svg	The base component used to render the ReactBrush. This can either be an svg or a g. In either case, props other than those specified here are passed on to the base component (if svg is used, width and height are also passed on).
mouseMoveThreshold	number	no	5	The number of pixels that the mouse needs to move after a mouse down before the brush starts.
mouseDownThreshold	number	no	500	The number of milliseconds after a mouse down before the start of a brush.

<BrushedArea> Props

Property	Type	Required	Default	Description
fullHeight	boolean	no	false	the brushed area will take up the full height of its container
fullWidth	boolean	no	false	the brushed area will take up the full width of its container