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How to Update the state in react redux-saga

I am newbie to react, redux-saga, I have a dropdown in page Display, when I select it move to respective component (eg. policy, score), In Component Pages, I have a button Add New, on clicking it will navigate to a page as mentioned in link url , which is a page having cancel button, on cancelling it returns to the Display.js but no dropdown selected,
I would like to keep the state articleMode, when navigating to a page and returning back to same page,
articleMode returns to state -1 instead of selected component Policy or Score
actions.js
export const updateArticleMode = data => {
console.log(data.body);
return {
type: CONSTANTS.UPDATE_ARTICLE_MODE,
data: data.body
};
};
queryReducer.js
import * as CONSTANTS from "../constants/constants";
const initialState = {
articleMode: ""
}
case CONSTANTS.UPDATE_ARTICLE_MODE: {
return {
...state,
articleMode: data.mode
};
}
export default queryReducer;
constants.js
export const UPDATE_ARTICLE_MODE = "UPDATE_ARTICLE_MODE";
Display.js
import React from "react";
import { connect } from "react-redux";
import Policy from "../policy";
import Score from "./../score";
import { updateArticleMode } from "../../../../actions/actions";
const articleMode = [
{ name: "Select", id: "-1" },
{ name: "Score", id: "Score" },
{ name: "Policy", id: "Policy" }
]
class Display extends React.PureComponent {
constructor(props) {
super(props);
this.state = {
articleMode: "-1"
};
}
componentWillMount = () => {
this.setState({ articleMode: this.props.queryData.articleMode || "-1" });
};
_getComponent = () => {
const { articleMode } = this.state;
if (articleMode === "Policy") {
return <DisplayPolicy></DisplayPolicy>;
}
if (articleMode === "Score") {
return <DisplayScore></DisplayScore>;
}
}
render() {
return (
<React.Fragment>
<select name="example"
className="simpleSearchSelect1"
value={this.state.articleMode}
onChange={event => {
this.setState({ articleMode: event.target.value });
this.props.dispatch(
updateArticleMode({ body: { mode: event.target.value } })
);
}}
style={{ marginLeft: "2px" }}
>
{articleMode.length != 0 &&
articleMode.map((option, index) => {
const { name, id } = option;
return (
<option key={index} value={id}>
{name}
</option>
);
})}
</select>
{this.state.articleMode === "-1"
? this._renderNoData()
: this._getComponent()}
</React.Fragment>
)}
const mapStateToProps = state => {
return {
queryData: state.queryData
};
};
export default connect(mapStateToProps)(Display);
}
DisplayPolicy.js
import React from "react";
class DisplayPrivacyPolicy extends React.Component {
constructor(props) {
super(props);
}<Link
to={{
pathname: "/ui/privacy-policy/addNew",
state: {
language: "en"
}
}}
>
<button className="page-header-btn icon_btn display-inline">
<img
title="edit"
className="tableImage"
src={`${process.env.PUBLIC_URL}/assets/icons/ic_addstore.svg`}
/>
{`Add New`}
</button>
</Link>
AddNew.js
<Link
to =pathname: "/ui/display",
className="btn btn-themes btn-rounded btn-sec link-sec-btn"
>
Cancel
</Link>

How do I access a function that is being updated from a redux store properly?

I have this component that I split for easy management. Before splitting everything worked as expected, after splitting I am getting an error when I click on an icon which calls the createReactionsIcon. Error says
TypeError: updateReaction is not a function
onClick
./components/home/components/SingleUpload.jsx:26
23 |
24 | return icons.map(({ key, text, type }) => (
25 | <IconText
> 26 | onClick={() => updateReaction(item.id, key)}
| ^ 27 | key={key}
28 | type={type}
29 | text={text}
How can I access this correctly from my Home component where updateReaction is returning updateReaction from the redux store.
SubComponent
import PropTypes from 'prop-types';
import React from 'react';
import { Avatar, Card, Icon, List } from 'antd';
import { LIST_TEXTS, STYLES } from '../constants';
const { AVATAR, CARD_CONTAINER, CARD_LIST, ICON, USER_LIST } = STYLES;
const { INNER, MORE, UPLOAD, VERTICAL } = LIST_TEXTS;
const IconText = ({ type, text, onClick }) => (
<span>
<Icon type={type} style={ICON} onClick={onClick} />
{text}
</span>
);
function createReactionsIcon(item, updateReaction) {
const { like, dislike, maybe } = item.reactions;
const icons = [
{ key: 'like', text: `${like.count}`, type: 'heart' },
{ key: 'dislike', text: `${dislike.count}`, type: 'dislike' },
{ key: 'maybe', text: `${maybe.count}`, type: 'meh' },
];
return icons.map(({ key, text, type }) => (
<IconText
onClick={() => updateReaction(item.id, key)}
key={key}
type={type}
text={text}
/>
));
}
export default class SingleUpload extends React.Component {
render() {
const { values } = this.props;
return (
<div style={CARD_CONTAINER}>
<List
itemLayout={VERTICAL}
dataSource={values}
renderItem={item => {
const { avatar, description, id, uploader: { image, name } } = item;
return (
<List.Item style={USER_LIST}>
<Card
actions={createReactionsIcon(item, this.updateReaction)}
cover={<img alt={UPLOAD} src={image} />}
extra={<Icon type={MORE} />}
hoverable
key={id}
title={(
<a href="/">
<Avatar src={avatar} style={AVATAR} />
{name}
</a>
)}
type={INNER}
style={CARD_LIST}
>
{description}
</Card>
</List.Item>
);
}}
/>
</div>
);
}
}
Home.js
import PropTypes from 'prop-types';
import React from 'react';
import { connect } from 'react-redux';
import { bindActionCreators } from 'redux';
import SingleUpload from './SingleUpload';
import ComparisonUpload from './ComparisonUpload';
import { STYLES } from '../constants';
import * as actions from '../actions';
import { getUploads } from '../selectors';
const { CARD_CONTAINER } = STYLES;
class Home extends React.Component {
componentDidMount() {
const { actions: { requestUploadList } } = this.props;
requestUploadList();
}
updateReaction = (id, reaction) => {
const { actions: { updateReaction } } = this.props;
const payload = { id, reaction };
updateReaction(payload);
}
render() {
const { uploads } = this.props;
return (
<div style={CARD_CONTAINER}>
<SingleUpload values={[...uploads.values()]} />
<ComparisonUpload values={[...uploads.values()]} />
</div>
);
}
}
Home.propTypes = {
actions: PropTypes.objectOf(PropTypes.object),
uploads: PropTypes.instanceOf(Map),
};
const mapStateToProps = state => ({
uploads: getUploads(state),
});
const mapDispatchToProps = dispatch => ({
actions: bindActionCreators(actions, dispatch),
});
export default connect(mapStateToProps, mapDispatchToProps)(Home);

Pass your function to component as props,
<SingleUpload values={[...uploads.values()]} updateReaction = {this.updateReaction}/>
Now you can use this in your child component,
<IconText onClick={() => this.props.updateReaction(item.id, key)}

You can pass the updateReaction from your parent to child as a callback
<SingleUpload values={[...uploads.values()]} hanldeReaction={this.updateReaction} />
And you can access it in the child using props.hanldeReaction
<Card actions={createReactionsIcon(item, this.props.hanldeReaction)}

You have to pass down the updateReaction() event-handler you defined in Home as a prop to SingleUpload. Then you can access that prop from anywhere inside your component.
Which means we can cleanup the actions prop inside the Card since we only need to pass the item now.
<Card actions={createReactionsIcon(item)}
As well as createReactionsIcon, now we just call that prop directly inside the function
function createReactionsIcon(item) {
const { like, dislike, maybe } = item.reactions;
const icons = [
{ key: 'like', text: `${like.count}`, type: 'heart' },
{ key: 'dislike', text: `${dislike.count}`, type: 'dislike' },
{ key: 'maybe', text: `${maybe.count}`, type: 'meh' },
];
return icons.map(({ key, text, type }) => (
<IconText
onClick={() => this.props.updateReaction(item.id, key)}
key={key}
type={type}
text={text}
/>
));
}
Less redundant code overall which sounds like what you are trying to achieve.

How to hide some component based on some flag in react js

I want to hide some component based on some flag in react js.
I have an App component where I have Login and other components, I want to hide the other component until Login components this.state.success is false and on click of a button I am changing the sate, but it's not working, I am new to react,
My App Class compoenent -
import React, { Component } from "react";
import logo from "../../logo.svg";
// import Game from "../Game/Game";
import Table from "../Table/Table";
import Form from "../Table/Form";
import Clock from "../Clock/Clock";
import "./App.css";
import Login from "../Login/Login";
class App extends Component {
state = {
success: false
};
removeCharacter = index => {
const { characters } = this.state;
this.setState({
characters: characters.filter((character, i) => {
return i !== index;
})
});
};
handleSubmit = character => {
this.setState({ characters: [...this.state.characters, character] });
};
handleSuccess() {
this.setState({ success: true });
}
render() {
const { characters, success } = this.state;
return (
<div className="App">
<header className="App-header">
<img src={logo} className="App-logo" alt="logo" />
<span className="Span-inline">App</span>
<Clock time={new Date()} />
</header>
<Login success={success} handleSuccess={this.handleSuccess} />
{success && (
<div className="container">
<h1>React Tutorial</h1>
<p>Add a character with a name and a job to the table.</p>
<Table
characterData={characters}
removeCharacter={this.removeCharacter}
/>
<h3>Add New character</h3>
<Form handleSubmit={this.handleSubmit} />
</div>
)}
{/* <Game /> */}
</div>
);
}
}
export default App;
My Login component -
import React, { Component } from "react";
import Greeting from "./Greeting";
import LogoutButton from "./LogoutButton";
import LoginButton from "./LoginButton";
class Login extends Component {
constructor(props) {
super(props);
this.handleLoginClick = this.handleLoginClick.bind(this);
this.handleLogoutClick = this.handleLogoutClick.bind(this);
this.state = {
isLoggedIn: false,
name: "",
success: false
};
}
handleLoginClick() {
this.setState({ isLoggedIn: true });
this.setState({ success: true });
}
handleLogoutClick() {
this.setState({ isLoggedIn: false });
this.setState({ success: false });
}
onChange = e => {
this.setState({
name: e.target.value
});
};
render() {
const isLoggedIn = this.state.isLoggedIn;
const name = this.state.name;
// const successLogin = this.state.success;
let button;
if (isLoggedIn) {
button = <LogoutButton onClick={this.handleLogoutClick} />;
} else {
button = <LoginButton onClick={this.handleLoginClick} />;
}
return (
<div>
<Greeting
isLoggedIn={isLoggedIn}
name={name}
onChange={this.onChange}
/>
{button}
</div>
);
}
}
export default Login;
please guide me on what I am doing wrong.
Why sometime debuggers do not trigger in react component?

For the sake of example I have used functional stateless component here. You can use Class component all upto you.
const conditionalComponent = (props) => {
let condition = true;
return (
{condition && <div><h1>Hello world</h1></div>}
}
Instead of directly giving condition you can even call function which returns a boolean value.

handleLoginClick() {
this.setState({ isLoggedIn: true });
this.setState({ success: true });
this.props.handleSuccess()
}
do like this
<Login success={success} handleSuccess=
{this.handleSuccess} />
bind this function

How to render the elements before to filter elements with ReactJS?

I'm doing a project which does a get of the json-server, and render them on the screen.
But when I added a filtering function on it, it only renders after I type a name to filter. I wanted him to render everyone and make the filter.
My Body.js (Where is my function of render):
import React from 'react';
import './Body.css';
import { Link } from "react-router-dom";
class Body extends React.Component {
constructor(props) {
super(props);
this.state = {
input: "",
employeeBody: this.props.employee,
}
}
getName = () => {
const { employee, add } = this.props;
const {employeeBody} = this.state;
return employee.map(name => (
<div className='item'>
<Link className="link" to={`/user/${name.id}`}>
<div onClick={() => add(name)} key={name.id}>
<img className="img"
src={`https://picsum.photos/${name.id}`}
/>
</div>
<h1 className="name2"> {name.name} </h1>
</Link>
</div>
));
};
---
getValueInput = (evt) => {
const inputValue = evt.target.value;
this.setState({ input: inputValue });
this.filterNames(inputValue);
console.log(this.state.employeeBody)
}
filterNames (inputValue) {
const { employee } = this.props;
this.setState({
employeeBody: employee.filter(item =>
item.name.includes(inputValue))
});
}
---
render() {
return (
<div>
<div className="body">
{this.getName()}
</div>
<div className='input'>
<input type="text" onChange={this.getValueInput} />
</div>
</div>
)
}
}
export default Body;
My App.js (Where i get the state by get of axios.):
import React from 'react';
import {
BrowserRouter as Router,
Route
} from "react-router-dom";
import './App.css';
import axios from 'axios';
import Body from './Body';
import User from './User';
import Header from './Header';
class AppRouter extends React.Component {
state = {
employeeCurrent: [],
employee: []
};
componentDidMount() {
axios
.get("http://127.0.0.1:3004/employee")
.then(response => this.setState({
employee: response.data
}));
}
add = name => {
this.setState(prevState => {
const copy = prevState.employeeCurrent.slice(1);
copy.push(name);
return {
employeeCurrent: copy
};
});
};
render() {
return ( <
Router >
<
div className = "router" >
<
Header / >
<
Route exact path = "/"
render = {
props => ( <
Body { ...props
}
add = {
this.add
}
employee = {
this.state.employee
}
employeeCurrent = {
this.state.employeeCurrent
}
/>
)
}
/> <
Route path = "/user/:id"
component = {
props => ( <
User { ...props
}
employee = {
this.state.employee
}
employeeCurrent = {
this.state.employeeCurrent
}
/>
)
}
/> <
/div> <
/Router>
);
}
}
export default AppRouter;
Someone would can help me ?

You should filter in the render method.
render() {
const { employee: employees } = this.props; // rename the variable {employee} to plural {employees}, it has more sense.
const { input } = this.state;
return (
<div>
<div className="body">
{employees
.filter(employee => employee.name.includes(input))
.map(employee => {
<div className='item'>
<Link className="link" to={`/user/${employee.id}`}>
<div onClick={() => add(employee)} key={employee.id}>
<img className="img"
src={`https://picsum.photos/${employee.id}`}
/>
</div>
<h1 className="name2"> {employee.name} </h1>
</Link>
</div>
})}
</div>
<div className='input'>
<input type="text" onChange={(e) => this.setState({ input: e.target.value })} />
</div>
</div>
);
}
Remember that the method includes is case sensitive, it should be lowerCase it before to compare.
P.S.: You could also create a variable / component / function and render split all the "logic" of rendering there.

How to avoid rerendering element in the array in react?

I have a array and I want to render the this array into a few redux forms. I found out that all the forms are rerendered. the code looks like the following:
Form.jsx
import React, { Component } from 'react';
import PropTypes from 'prop-types';
import { Link, Events, scrollSpy } from 'react-scroll';
import styles from './Form.css';
import MultipleForm from './MultipleForm';
class Form extends Component {
constructor(props) {
super(props);
const {
workflows,
} = this.props;
this.state = {
curTab: workflows.length > 0 ? workflows[0] : '',
curForm: '',
};
}
componentDidMount() {
Events.scrollEvent.register('begin');
Events.scrollEvent.register('end');
scrollSpy.update();
}
componentWillReceiveProps(nextProps) {
const {
workflows,
} = nextProps;
if (workflows && workflows.length > this.props.workflows) {
this.setState({
curTab: workflows[0],
});
}
}
componentWillUnmount() {
Events.scrollEvent.remove('begin');
Events.scrollEvent.remove('end');
}
handleChangeTab = (value) => {
this.setState({
curTab: value,
});
}
handleActiveTab = (workflow) => {
console.log(workflow);
}
render() {
const {
workflows,
schemaNames,
...rest
} = this.props;
return (
<div className={styles.container}>
<header>
<PerspectiveBar
value={this.state.curTab}
onChange={this.handleChangeTab}
style={{
position: 'fixed',
left: '0',
top: '48px',
width: '100vw',
zIndex: '1380',
}}
>
{workflows.map(wf => (
<PerspectiveTab
key={wf}
label={wf}
value={wf}
onActive={() => this.handleActiveTab(wf)}
/>
))}
</PerspectiveBar>
</header>
<div className={styles.formContainer}>
<Paper className={styles.paperContainer}>
<MultipleForm
workflow={this.state.curTab}
schemaNames={schemaNames}
{...rest}
/>
</Paper>
</div>
<Drawer className={styles.drawer} containerStyle={{ height: 'calc(100% - 104px)', top: '104px' }}>
<div className={styles.drawerContainer}>
{schemaNames.map(schemaName => (
<Link
onSetActive={(to) => {
this.setState({
curForm: to,
});
}}
to={schemaName}
duration={500}
offset={-104}
spy
smooth
>
<MenuItem
checked={this.state.curForm === schemaName}
>
{schemaName}
</MenuItem>
</Link>
))}
</div>
</Drawer>
</div>
);
}
}
Form.propTypes = {
schemaNames: PropTypes.arrayOf(PropTypes.string),
workflows: PropTypes.arrayOf(PropTypes.string),
fetchSchemaNames: PropTypes.func.isRequired,
};
Form.defaultProps = {
schemaNames: [],
workflows: [],
};
export default Form;
MultipleForm.jsx
import React, { Component } from 'react';
import PropTypes from 'prop-types';
import FlatButton from 'material-ui/FlatButton';
import { Element } from 'react-scroll';
import SchemaForm from './SchemaForm';
class MultipleForm extends Component {
componentDidMount() {
console.log('MultipleForm Mounted');
const {
workflow,
fetchSchemaNames,
} = this.props;
if (workflow) fetchSchemaNames(workflow);
}
componentWillReceiveProps(nextProps) {
const {
workflow,
fetchSchemaNames,
} = nextProps;
if (workflow && this.props.workflow !== workflow) fetchSchemaNames(workflow);
}
componentDidUpdate() {
const {
schemaNames,
schemas,
initialValues,
fetchSchemas,
fetchInitialValues,
} = this.props;
const schemasNeedToFetch = this.remainingSchemas(schemaNames, schemas);
if (schemasNeedToFetch.length !== 0) fetchSchemas(schemasNeedToFetch);
const initialValuesNeedToFetch = this.remainingInitialValues(schemaNames, initialValues);
if (initialValuesNeedToFetch.lenght !== 0) fetchInitialValues(initialValuesNeedToFetch, 1);
}
remainingSchemas = (schemaNames, schemas) =>
schemaNames.filter(schemaName => schemaName in schemas === false).sort();
remainingInitialValues = (schemaNames, initialValues) =>
schemaNames.filter(schemaName => schemaName in initialValues === false).sort();
handleSubmitAll = (event) => {
event.preventDefault();
const {
submit,
schemas,
schemaNames,
} = this.props;
schemaNames
.map(schemaName => schemas[schemaName].title)
.forEach((title) => {
submit(title);
});
}
render() {
const {
schemaNames,
schemas,
initialValues,
postForm,
} = this.props;
schemaNames.sort((a, b) => a.localeCompare(b));
return (
<div>
{schemaNames.map(schemaName => (
<Element name={schemaName}>
<SchemaForm
key={schemaName}
schema={schemas[schemaName]}
initialValue={initialValues[schemaName]}
schemaName={schemaName}
postForm={postForm}
/>
</Element>
))}
<div>
<FlatButton
label="Submit"
/>
<FlatButton label="Deploy" />
</div>
</div>);
}
}
MultipleForm.propTypes = {
workflow: PropTypes.string.isRequired,
submit: PropTypes.func.isRequired,
fetchSchemaNames: PropTypes.func.isRequired,
schemas: PropTypes.object,
schemaNames: PropTypes.arrayOf(PropTypes.string),
initialValues: PropTypes.object,
fetchSchemas: PropTypes.func.isRequired,
fetchInitialValues: PropTypes.func.isRequired,
postForm: PropTypes.func.isRequired,
};
MultipleForm.defaultProps = {
schemaNames: [],
};
export default MultipleForm;
SchemaForm
import React, { Component } from 'react';
import PropTypes from 'prop-types';
import Liform from 'liform-react';
import theme from './NokiaTheme';
import styles from './Form.css';
class SchemaForm extends Component {
componentDidMount() {
console.log('schema mounted');
}
shouldComponentUpdate() {
return false;
}
handleSubmit = (value) => {
const {
postForm,
schemaName,
} = this.props;
postForm(value, schemaName, 1);
}
render() {
const {
schema,
initialValue,
} = this.props;
console.log('props', this.props);
return (
<div>
<h3 id={schema.$id} className={styles.formTitle}>
{schema.title}
</h3>
<Liform
schema={schema}
onSubmit={value => this.handleSubmit(value)}
destroyOnUnmount={false}
theme={theme}
initialValues={initialValue}
/>
</div>
);
}
}
SchemaForm.propTypes = {
schema: PropTypes.shape({
$id: PropTypes.string,
}),
initialValue: PropTypes.object,
schemaName: PropTypes.string,
postForm: PropTypes.func.isRequired,
};
SchemaForm.defaultProps = {
schema: {},
initialValue: null,
schemaName: '',
};
export default SchemaForm;
the schemaNames will be changed only by adding or deleting some element. for example: the schemaNames will change from ['A', 'B', 'C'] to ['A', 'B', 'D']. I get the schemaNames from the redux. which I fetch online.
But when I check the ConnectedReduxForm, when I change the schemaNames, the SchemaForm will be unmounted and the react will mount the form again. I have tried with setting the ConnectedReduxForm to be PureComponent. It is not helpful.
Could someone help me with that? I have spent a lot of time of this and nothing helps.
Update: I have found the problem, the reason of it is that for each time that I for each time I update the workflow, I need to fetch the schemaNames from the server. But I still do not know why this happended. Could someone explain that?