Ezek Ezek - 1 month ago 8
React JSX Question

Redux - the app does not re-render after dispatching

I'm new to react + redux. I encountered a problem which my app is not re-render when I dispatch an action. However, I use getState() to examine the state, it did change. I look up documents but still have no idea what the problem is. Please help me, thanks.

The code is as below

====actions.js====

export const ADD_MAIL = 'ADD_MAIL';
export const DEL_MAIL = 'DEL_MAIL';

export function addMail(email) {
return {
type: ADD_MAIL,
email
}
}

export function delMail(id) {
return {
type: DEL_MAIL,
id
}
}


====reducers.js====

import { combineReducers } from 'redux'
import { ADD_MAIL, DEL_MAIL } from '../actions/actions'
import MAILS from '../data'

function emails(state = MAILS, action) {
switch (action.type) {
case ADD_MAIL:
console.log("ADD_MAIL");

return [
action.email,
...state
];

case DEL_MAIL:
let idx = state.length;
let i = 0;

// Find the target mail
while(idx--) {
if (state[idx] && state[idx].serialNo === action.id)
i = idx;
}

let arr1 = state.slice(0, i);
let arr2 = state.slice(i + 1);

let newList = arr1.concat(arr2);

console.log("DEL_MAIL");
return newList;

default:
return state;
}
}

const rootReducer = combineReducers({
emails
});

export default rootReducer;


====main.js====

import React from 'react'
import { render } from 'react-dom'
import { Link } from 'react-router'
import { connect } from 'react-redux'
import { createStore } from 'redux'
import { addMail, delMail } from './actions/actions'
import rootReducer from './reducers/reducers'
import * as btn from './module/button'
import * as module from './module/module'


var store = createStore(rootReducer);

class Inbox extends React.Component {
constructor(props) {
super(props);
this.state = {
searchText: ''
}
this.handleUserInput = this.handleUserInput.bind(this);
this.deleteMail = this.deleteMail.bind(this);
this.sendMail = this.sendMail.bind(this);
}

handleUserInput(searchText) {
this.setState({
searchText: searchText
});
}

deleteMail(obj) {
store.dispatch(delMail(obj.serialNo));
console.log(store.getState());
// This displays the correct new state in console after dispatch
}

sendMail(newMail) {
store.dispatch(addMail(newMail));
console.log(store.getState());
// This displays the correct new state in console after dispatch
}

render() {
let mails = [];
let search = this.state.searchText.toUpperCase();

let emails = this.props.emails;
emails.map(mail => {
if (mail.from.toUpperCase().indexOf(search) !== -1)
mails.push(mail);
});

let sender = (mails.length === emails.length) ? "all" : this.state.searchText;

return (
<div className="main">
<div className="toolbar">
<span>You have {mails.length} message from {sender}.</span>
<module.SearchInput searchText={this.state.searchText} onUserInput={this.handleUserInput} />
<div className="functions">
<btn.AddButton />
</div>
</div>

<div className="mailList">
{mails.map(mail => (
<div className="item" key={mail.serialNo}>
<div className="info sender">
From: {mail.from}
</div>
<div className="info date">
{mail.date}
</div>
<div className="info subject">
Subject: {mail.subject}
</div>
<div className="functions">
<btn.ReadButton serialNo={mail.serialNo} />
<btn.DeleteButton serialNo={mail.serialNo} deleteMail={this.deleteMail} />
</div>
</div>
))}
</div>

<module.NewMailInput sendMail={this.sendMail} />
</div>
);
}
}

function mapStateToProps(state) {
return {
emails: state.emails
};
}

export default connect(mapStateToProps)(Inbox);


====app.js====

import React from 'react'
import { render } from 'react-dom'
import { Router, Route, IndexRoute, browserHistory } from 'react-router'
import { createStore } from 'redux'
import { Provider } from 'react-redux'
import { Menu } from './menu'
import { Mail } from './main'
import Inbox from './main'
import rootReducer from './reducers/reducers'

var store = createStore(rootReducer);

class App extends React.Component {
constructor(props) {
super(props);
}

render() {
return (
<div style={{height: '100%'}}>
<Menu />
{this.props.children}
</div>
);
}
}

class Home extends React.Component {
constructor(props) {
super(props);
}

render() {
return (
<Inbox />
);
}
}

render(
<Provider store={store}>
<Router history={browserHistory}>
<Route path="/" component={App}>
<IndexRoute component={Home} />
<Route path="/inbox" component={Inbox} />
<Route path="/message/:mailSerial" component={Mail} />
</Route>
</Router>
</Provider>,
document.getElementById('app-container'))

Answer

Try this:

import React from 'react'
import { render } from 'react-dom'
import { Link } from 'react-router'
import { connect } from 'react-redux'
import { addMail, delMail } from './actions/actions'
import * as btn from './module/button'
import * as module from './module/module'

class Inbox extends React.Component {
    constructor(props) {
    super(props);
    this.state = {
      searchText: ''
    }
    this.handleUserInput = this.handleUserInput.bind(this);
    this.deleteMail = this.deleteMail.bind(this);
    this.sendMail = this.sendMail.bind(this);
  }

  handleUserInput(searchText) {
    this.setState({
      searchText: searchText
    });
  }

  deleteMail(obj) {
    this.props.delMail(obj.serialNo); //Call the delMail action
    console.log(store.getState());
  }

  sendMail(newMail) {
    this.props.addMail(newMail); //Call the addMail action
    console.log(store.getState());
  }

  render() {
    let mails = [];
    let search = this.state.searchText.toUpperCase();

    let emails = this.props.emails;
    emails.map(mail => {
      if (mail.from.toUpperCase().indexOf(search) !== -1)
        mails.push(mail);
    });

    let sender = (mails.length === emails.length) ? "all" : this.state.searchText;

    return (
      <div className="main">
        <div className="toolbar">
          <span>You have {mails.length} message from {sender}.</span>
          <module.SearchInput searchText={this.state.searchText} onUserInput={this.handleUserInput} />    
          <div className="functions">
            <btn.AddButton />
          </div>  
        </div>

        <div className="mailList">
            {
            mails.map(mail => (
                <div className="item" key={mail.serialNo}>
                    <div className="info sender">From: {mail.from}</div>
                    <div className="info date">{mail.date}</div>
                    <div className="info subject">Subject: {mail.subject}</div>
                    <div className="functions">
                        <btn.ReadButton serialNo={mail.serialNo} />
                        <btn.DeleteButton serialNo={mail.serialNo} deleteMail={this.deleteMail} />
                    </div>
                </div>
            ))
          }
        </div>
          <module.NewMailInput sendMail={this.sendMail} />
      </div>
        );
    }
}

function mapStateToProps(state) {
    return {
      emails: state.emails
    }; 
}

//Connect the component to re-render when state change and 
// makes the emails and actions to be available through this.props
export default connect(mapStateToProps, {delMail, addMail})(Inbox);