React-router:从路由器获取参数，监听事件失败

我发现，当尝试使用react-router router.listen(…)获取路由参数时，它失败了。通过使用window.location.pathname.split('route/')[1]，我可以获得参数。有什么建议吗?

我一直在试图弄清楚为什么会发生这种情况。到目前为止，我注意到它在第一次路由更改(url更改)上失败了-我的意思是，通过使用，我的url从/param/y更改为/param/x;但该参数只有在我再次单击时才可用。我想这可能与我的行为或我的组件有关?或者侦听器在react生命周期中的位置?

不确定我是否在错误的生命周期方法中声明事件监听器或;正如我一直在想的那样，我正在将路由传递给Store，但我正在使用withouter (Component)来处理这个事件。我想我需要使用redux的路由状态。我认为

具有侦听器的组件:

import React, { Component } from 'react';
import { connect } from 'react-redux';
import { withRouter } from 'react-router';
import { setActiveQuestion, setQuestionAnswer } from '../actions/index';
import { bindActionCreators } from 'redux';
import { Link } from 'react-router';
import Navbar from '../containers/navbar';
class Question extends Component {
    constructor(props) {
        super(props);
        this.getClassName = this.getClassName.bind(this);
    }
    componentWillMount() {
        this.setEventListeners();
    }
    setEventListeners() {
        this.props.router.listen(() => {
            // using location pathname instead, since props.params fail
            //let question_id = this.props.params.question_id;
            let question_id = window.location.pathname.split('question/')[1]
            this.props.setActiveQuestion(question_id);
        });
    }
    setAnswer(answer_id) {
        let question_id = this.props.question.id;
        this.props.setQuestionAnswer(question_id, answer_id);
    }
    getClassName(answers, item_answer_id) {
        let classes = [];
        // find the answer for the active question
        let answer_index = _.findIndex(answers, (answer) => {
            return answer.question_id === this.props.question.id;
        });
        // if there's no answer yet, skip class placement
        if (answer_index === -1) {
            return;
        }
        let answer = answers[answer_index];
        // Test cases
        const isUserCorrect = () => {
            return answer.answer_id == answer.correct_answer_id && item_answer_id == answer.correct_answer_id
        }
        const isUserAnswer = () => {
            return answer.answer_id === item_answer_id;
        }
        const isCorrectAnswer = () => {
            return item_answer_id == answer.correct_answer_id;
        }
        // Test and set the correct case classname for styling
        if (isUserCorrect()) {
            classes.push('user_correct_answer');
        }
        if (isUserAnswer()) {
            classes.push('user_answer');
        }
        if (isCorrectAnswer()) {
            classes.push('correct_answer');
        }
        return classes.length > 0 ? classes.join(' ') : '';
    }
    answersList() {
        return this.props.question.answers.map((answer) => {
            return <li className={ this.getClassName(this.props.answers, answer.id) } key={ answer.id } onClick={ () => this.setAnswer(answer.id) }>{ answer.text }</li>
        });
    }
    render() {
        return (
            <div>
                <div className='question-container'>
                    <h2>{ this.props.question && this.props.question.question }</h2>
                    <ul>
                    {
                        this.props.question &&
                        this.answersList()
                    }
                    </ul>
                </div>
                <Navbar />
            </div>
        );
    }
}
function mapStateToProps(state, ownProps) {
    return {
        question: state.questions.active,
        answers: state.answers
    }
}
function matchDispatchToProps(dispatch) {
    return bindActionCreators({
        setActiveQuestion: setActiveQuestion,
        setQuestionAnswer: setQuestionAnswer
    }, dispatch);
}
export default connect(mapStateToProps, matchDispatchToProps)(withRouter(Question));

这里是减速器:

import { FETCH_QUESTIONS, SET_ACTIVE_QUESTION } from '../actions/index';
import _ from 'lodash';
const INITIAL_STATE = {
    loading: true,
    list: [],
    active: 0
};
export default function(state = INITIAL_STATE, action) {
    switch (action.type) {
        case FETCH_QUESTIONS:
            return Object.assign({}, state, {
                loading: false,
                list: action.payload
            });
        break;
        case SET_ACTIVE_QUESTION:
            // retrieve the active question by the route param `question id`
            let question_id = parseInt(action.payload);
            let question = _.find(state.list, function (question) {
                return question.id === question_id;
            });
            return Object.assign({}, state, {
                active: question
            });
        break;
        default:
            return state;
    }
};

应用入口点index.js:

import React from 'react';
import ReactDOM from "react-dom";
import { Router, browserHistory } from 'react-router';
import { syncHistoryWithStore } from 'react-router-redux'
import { createStore, applyMiddleware } from 'redux';
import { Provider } from 'react-redux';
import routes from './config/routes';
import reducers from './reducers';
import promise from 'redux-promise';
const createStoreWithMiddleware = applyMiddleware(promise)(createStore);
const store = createStoreWithMiddleware(reducers);
const history = syncHistoryWithStore(browserHistory, store);
ReactDOM.render(
    <Provider store={ store }>
        <Router history={ history } routes={ routes } />
    </Provider>,
    document.getElementById('app')
);

router.js文件:

import { combineReducers } from 'redux';
import questionsReducer from './reducer_questions';
import answerReducer from './reducer_answers';
import { routerReducer } from 'react-router-redux'
const rootReducer = combineReducers({
    questions: questionsReducer,
    answers: answerReducer,
    routing: routerReducer
});
export default rootReducer;