React Performance: requestAnimationFrame Example

requestAnimationFrame.js

// How to ensure that our animation loop ends on component unount

componentDidMount() {
  this.startLoop();
}

componentWillUnmount() {
  this.stopLoop();
}

startLoop() {
  if( !this._frameId ) {
    this._frameId = window.requestAnimationFrame( this.loop );
  }
}

loop() {
  // perform loop work here
  this.theoreticalComponentAnimationFunction()
  
  // Set up next iteration of the loop
  this.frameId = window.requestAnimationFrame( this.loop )
}

stopLoop() {
  window.cancelAnimationFrame( this._frameId );
  // Note: no need to worry if the loop has already been cancelled
  // cancelAnimationFrame() won't throw an error
}