Function willUnmount

src/notification/NotificationCenter.jsx:34–47

(height, top)

  const element = React.createElement(Notification, Object.assign({}, props, {
    willUnmount(height, top) {
      setTimeout(() => document.body.removeChild(div));
      requestAnimationFrame(() => {
        const instances = document.querySelectorAll(className);
        const len = instances.length;
        for (let i = 0; i < len; i++) {
          const element = instances[i];
          const elementTop = parseInt(element.style.top);
          if (elementTop > top) {
            element.style.top = `${elementTop - height - 16}px`;
          }
        }
      })
    }
  }));

  ReactDOM.render(element, div);