How to use the react-onsenui.RouterUtil.postPush function in react-onsenui

onPostPush() {
    const routeConfig = RouterUtil.postPush(this.state.routeConfig);
    this.setState({routeConfig});
  }

const reducer = (state = initialState, action) => {
  let routeConfig;

	switch(action.type) {
		case 'PUSH_PAGE':
      const {route} = action;
      routeConfig = state;
      return RouterUtil.push({routeConfig, route});
		case 'POST_PUSH':
      return RouterUtil.postPush(state);
		case 'POP_PAGE':
      routeConfig = state;
      return RouterUtil.pop({routeConfig});
		case 'POST_POP':
      return RouterUtil.postPop(state);
		default:
			return state;
	}
};