lazy_loading_hoc.jsx

export const withLazyLoading = (getComponent, { LoaderComponent = null }) =>
    class WithLazyLoading extends React.Component {
        state = {
            Component: null,
        }

        componentWillMount() {
            const { startLoading, stopLoading } = this.props

            startLoading()

            getComponent()
                .then(({ default: component }) => {
                    stopLoading()
                    this.setState({ Component: component })
                })
                .catch(err => {
                    stopLoading(err)
                })
        }

        render() {
            const { Component } = this.state

            const { onStartLoading, onFinishLoading, ...rest } = this.props

            return Component === null
                ? <LoaderComponent />
                : <Component {...rest} />
        }
    }