react-spring/src/animated/AnimatedWithChildren.js

Animate React with ease

import Animated from './Animated'
import AnimatedTracking from './AnimatedTracking'

export default class AnimatedWithChildren extends Animated {
  constructor() {
    super()
    this._children = []
  }

  __addChild(child) {
    if (this._children.length === 0) this.__attach()
    this._children.push(child)
  }

  __removeChild(child) {
    const index = this._children.indexOf(child)
    if (index === -1) {
      console.warn("Trying to remove a child that doesn't exist")
      return
    }
    this._children.splice(index, 1)
    if (this._children.length === 0) this.__detach()
  }

  __getChildren() {
    return this._children
  }
}