I've got 3 components as follows and the first on change on the input field makes it lose focus. I've tried giving the input fields and divs keys but it didn't solve my problem. I'm new to React so I might be doing something basic incorrectly. I'm not creating a new function inside a render method which is the reason for most losing focus issues documented in stackoverflow. Hence the reason for the new post.
Index.tsx
import * as React from "react";
import { IQuery, Queries } from "./components/Queries/Queries";
interface IManageResponseState {
primaryQuery: IQuery;
alternateQueries: IQuery[];
}
export class ManageResponse extends React.Component<any, IManageResponseState> {
constructor(props: any) {
super(props);
this.state = {
primaryQuery: {
queryText: "This is my primary query text",
id: 0
}, alternateQueries: [{
queryText: "this is my alternate query text 1",
id: 1
},
{
queryText: "this is my alternate query text 2",
id: 2
}]
};
this.addFunc = this.addFunc.bind(this);
this.removeFunc = this.removeFunc.bind(this);
this.primaryChangedFunc = this.primaryChangedFunc.bind(this);
this.alternateChangedFunc = this.alternateChangedFunc.bind(this);
}
public addFunc(text: string) {
const newQueries = this.state.alternateQueries.filter(q => true);
newQueries.push({ id: 0, queryText: text });
this.setState({ alternateQueries: newQueries });
};
public removeFunc(index: number) {
this.setState({ alternateQueries: this.state.alternateQueries.splice(index, 1) });
console.log("Remove called:" + index);
};
public primaryChangedFunc(text: string) {
const query = {
queryText: text,
id: 0
};
this.setState({ primaryQuery: query });
console.log("changed primary called:" + text);
}
public alternateChangedFunc(index: number, text: string) {
const item = this.state.alternateQueries[index];
const newQueries = this.state.alternateQueries.filter(q => true);
newQueries[index] = {
queryText: text,
id: item.id
};
this.setState({ alternateQueries: newQueries })
console.log("changed alternate called:" + text);
}
public render() {
return (
<React.Fragment>
<Queries primaryQuery={this.state.primaryQuery} alternateQueries={this.state.alternateQueries} onAddQuery={this.addFunc} onRemoveQuery={this.removeFunc} onPrimaryChanged={this.primaryChangedFunc} onAlternateQueryChanged={this.alternateChangedFunc} />
</React.Fragment>
);
}
}
Queries.tsx
import * as classnames from 'classnames';
import * as React from "react";
import { AlternateQueryItem } from "../AlternateQueryItem/AlternateQueryItem";
import './Queries.scss'
export interface IQuery {
queryText: string;
id: number;
}
export interface IQueryProps {
primaryQuery: IQuery;
alternateQueries: IQuery[];
onPrimaryChanged: (queryText: string) => void;
onAlternateQueryChanged: (index: number, queryText: string) => void;
onAddQuery: (queryText: string) => void;
onRemoveQuery: (atIndex: number) => void;
}
interface IQueryState {
primaryQueryInvalid: boolean;
}
class Queries extends React.Component<IQueryProps, IQueryState> {
constructor(props: IQueryProps) {
super(props);
this.onPrimaryQueryChanged = this.onPrimaryQueryChanged.bind(this);
this.state = { primaryQueryInvalid: false };
}
public render() {
return (
<main className="query-main-container">
<div className="primary-query-container">
<div className="form-group">
<h5 className={classnames("primary-query-header", { 'invalid': this.state.primaryQueryInvalid })}>Primary query</h5>
<div className="primary-query">
<div>{ "hello " + this.state.primaryQueryInvalid }</div>
<input type="text" value={this.props.primaryQuery.queryText} onChange={this.onPrimaryQueryChanged} className="form-control"/>
</div>
</div>
</div>
<div>
<h5 className="query-header">Query variations</h5>
<hr />
</div>
<div className="query-container">
{this.props.alternateQueries && this.props.alternateQueries.map((q, i) => this.renderQuery(q, i))}
</div>
</main>
);
}
public renderQuery(query: IQuery, key: number) {
return (
<AlternateQueryItem onChanged={this.props.onAlternateQueryChanged} query={query} key={key} index={key} />
);
}
private onPrimaryQueryChanged = (ev: React.FormEvent<HTMLInputElement>) => {
this.setState({ primaryQueryInvalid: ev.currentTarget.value === ""})
this.props.onPrimaryChanged(ev.currentTarget.value)
}
}
export { Queries };
AlternateQueryItem.tsx
import * as React from "react";
import { IQuery } from "../Queries/Queries";
export interface IAlternateQueryProps {
query: IQuery;
onChanged: (index: number, queryText: string) => void;
index: number;
}
class AlternateQueryItem extends React.Component<IAlternateQueryProps> {
constructor(props: IAlternateQueryProps) {
super(props);
this.onItemChanged = this.onItemChanged.bind(this);
}
public render() {
return (
<div className="form-group">
<div className="alternate-query">
<input type="text" value={this.props.query.queryText} onChange={this.onItemChanged} className="form-control" />
</div>
</div>
);
}
public onItemChanged = (ev: any) => {
this.props.onChanged(this.props.index, ev.currentTarget.value)
}
}
export { AlternateQueryItem };
Related
excuse me for that probably stupid question but this is my first steps with graphql and react. I try to create component where inside is GraphQL query, and incoming props. Props is a query which should by pass into GraphQL query. I know I do something wrong but I don't know what. I add everything like client with apollo provider into my app component structure.
On a main page (index.js) I have simply layout like:
import Layout from "../components/layout"
import SearchForm from "../components/searchForm"
export default function Home() {
return (
<Layout pageTitle="React App" headerTitle="Search repositories on Github">
<SearchForm repositoryNameDefaultValue='' />
</Layout>
);
}
then I have component called searchForm:
import { Component, ChangeEvent } from "react";
import Input from "./input";
import Button from "./button";
import style from "./searchForm.module.scss";
import FindRepositoryResults from "./test";
interface IMyComponentErrors {
repositoryNameError: string;
}
interface IMyComponentProps {
repositoryNameDefaultValue: string;
}
interface IMyComponentState {
repositoryName: string;
formIsSend: boolean;
errors: IMyComponentErrors;
}
const validateForm = (errors: IMyComponentErrors): boolean => {
let valid = true;
Object.values(errors).forEach((val) => val.length > 0 && (valid = false));
return valid;
};
const validRepositoryNameRegex = RegExp(/^[A-Za-z0-9 _]*[A-Za-z0-9][A-Za-z0-9 _]*$/i);
export default class SignUpFormContainer extends Component<
IMyComponentProps,
IMyComponentState
> {
constructor(props: IMyComponentProps) {
super(props);
this.state = {
repositoryName: this.props.repositoryNameDefaultValue,
formIsSend: false,
errors: {
repositoryNameError: "",
}
};
this.handleFormSubmit = this.handleFormSubmit.bind(this);
this.handleClearForm = this.handleClearForm.bind(this);
this.handleChangeRepositoryName = this.handleChangeRepositoryName.bind(this);
}
handleChangeRepositoryName(event: ChangeEvent<HTMLInputElement>): void {
event.preventDefault();
const { value } = event.target;
let errors = this.state.errors;
if (!validRepositoryNameRegex.test(value)) {
errors.repositoryNameError = "Invalid repository name";
} else if (!value) {
errors.repositoryNameError = "Repository name is required";
} else {
errors.repositoryNameError = "";
}
this.setState({ errors, repositoryName: value });
}
handleClearForm() {
this.setState({
repositoryName: "",
formIsSend: false
});
}
handleFormSubmit(event) {
event.preventDefault();
const { repositoryName } = this.state;
let errors = this.state.errors;
if (!repositoryName) {
errors.repositoryNameError = "Repository name is required";
}
this.setState({ errors });
if (!validateForm(this.state.errors)) {
return;
} else {
this.setState({ formIsSend: true });
}
}
render() {
const { errors } = this.state;
return (
<div>
{ !this.state.formIsSend ? (
<form
aria-label="Search repositories by name"
autoComplete="off"
onSubmit={this.handleFormSubmit}
className = {style.formSearchRepository}
>
<Input
type={"text"}
title={"Repository name:"}
name={"repositoryName"}
placeholder={"Enter name of repository"}
value={this.state.repositoryName}
error={errors.repositoryNameError.length > 0}
errorMessage={errors.repositoryNameError}
onChange={this.handleChangeRepositoryName}
required
/>
<Button
onClick={this.handleFormSubmit}
title={"Search repository in Github by name"}
children={"Search"}
/>
</form>
) : <FindRepositoryResults repositoryName={this.state.repositoryName}/>}
</div>
);
}
}
and last one that more problematic where is query:
import React from "react";
import { gql, useQuery } from "#apollo/client";
const SEARCH_REPOSITORY = gql`
query findRepositories($query: String!) {
search(first: 10, query: $query, type: REPOSITORY) {
nodes {
... on Repository {
name,
owner {
login
}
primaryLanguage {
name
},
stargazers {
totalCount
},
stargazerCount,
languages(first: 20, orderBy: {field: SIZE, direction: ASC} ) {
totalCount
nodes {
name
}
},
issues {
totalCount
}
shortDescriptionHTML,
updatedAt,
watchers {
totalCount
}
}
}
}
}
`;
interface IFindRepositoryComponentProps {
repositoryName: string;
}
interface IFindRepositoryComponentState {
detailsAreOpen: boolean;
}
interface RepositoryData {
data: any;
}
interface RepositoryVars {
query: string;
}
export default class FindRepositoryResults extends React.Component<IFindRepositoryComponentProps, IFindRepositoryComponentState> {
constructor(props: IFindRepositoryComponentProps) {
super(props);
this.state = { detailsAreOpen: false };
this.showDetails = this.showDetails.bind(this);
}
showDetails() {
this.setState(state => ({
detailsAreOpen: !state.detailsAreOpen
}));
}
render() {
const { loading, data, error } = useQuery<any, RepositoryVars>(
SEARCH_REPOSITORY ,
{ variables: { query: this.props.repositoryName } }
);
return (
<section>
<h3>Results</h3>
{loading ? (
<p>Loading ...</p>
) : error ? (<p>Error {error}</p>) : (
<div>
{ data.search.nodes.length == 0 ? (<p>No results found.</p>) : data && data.search.nodes.map((repo) => (
<div>
<p>Name: {repo.name}</p>
<p>Owner: {repo.owner.login}</p>
<p>Number of stars (total): {repo.stargazerCount}</p>
<p>Primary language: {repo.primaryLanguage.name}</p>
<button onClick={this.showDetails}>{this.state.detailsAreOpen ? 'Show less' : 'Show more'}</button>
<div>
Details:
{repo.issues.totalCount}
{repo.languages.totalCount}
{repo.shortDescriptionHTML}
{repo.stargazers.totalCount}
{repo.updatedAt}
{repo.watchers.totalCount}
</div>
</div>
))}
</div>
)}
</section>
);
}
}
In this component above I made query but I don't get results. I'm not sure but is mismatching of version (DOM Rendering), I have a problem to do this correctly together with typescript, react and apollo. I'll happy if any one can show me correct way and example how this should be done. Thank you
I haven't used typescript, but React hooks and GraphQL. So you made the query but you don't get any results? If the query is executed then there should be a result or an error. If it goes that far it could help to download the Apollo-Graphql plugin (to Google Chrome perhaps?).
I would try the query in the graphi-ql playground for example.
Also, variable-name query inside of your query is a bit confusing.
Best, J
I am really novice to React and I am stuck with this one.
I want to pass data from NewAction component to its parent NewActionSet.
I dont know what i am missing.
I am developing an on-boarding platform with a lot a components and I aim to send all the data entered into all the components to a server.
React parent Component:
import React from 'react'
import './NewActionSet.css'
import axios from 'axios'
import { Container, Segment, Header, Input } from 'semantic-ui-react'
import NewAction from './NewAction'
import 'bootstrap/dist/css/bootstrap.min.css'
class NewActionSet extends React.Component {
constructor (props) {
super(props)
this.state = {
actions: [],
actionType: '',
actionValue: '',
creationStatus: undefined
}
}
handleActions = value => {
this.setState({
actionsList: value
})
console.log(this.state.actionsList)
}
handleSubmit = event => {
event.preventDefault()
console.log(this.state)
axios
.post(
'/assistant/actions/',
{ ...this.state.values },
{ headers: {
xsrfHeaderName: 'X-CSRFToken',
xsrfCookieName: 'csrftoken'
},
withCredentials: true
}
)
.then(response => {
console.log(response)
this.setState({
creationStatus: true
})
})
.catch(error => {
console.log(error)
this.setState({
creationStatus: false
})
})
}
addNewAction = () => {
let { actions } = this.state
this.setState({
actions: [...actions, <NewAction onNewAction={this.handleActionstoParent} />]
})
}
handleActionstoParent = (action2Value, selectedAction) => {
this.setState({
actionType : selectedAction,
actionValue : action2Value
})
// console.log(this.state.actionType, this.state.actiondValue)
}
renderActions () {
return this.state.actions.map((action, index) => {
return (
<NewAction
key={index}
type={this.props.actionType}
content={action.content}
onNewAction={this.handleActionstoParent}
/>
)
})
}
render () {
let index = 0
return (
<Container>
<Header> Action sets </Header>
<Header color='grey' as='h3'>
SET #{index + 1}
</Header>
{this.renderActions()}
<button onClick={() => this.addNewAction()}> New Action </button>
</Container>
)
}
}
export default NewActionSet
React child component
import React from 'react'
import './NewActionSet.css'
import { Header, Dropdown } from 'semantic-ui-react'
import NewSpeechText from './NewSpeechText'
import NewAddPageURL from './NewAddPageURL'
import 'bootstrap/dist/css/bootstrap.min.css'
class NewAction extends React.Component {
constructor (props) {
super(props)
this.state = {
availableActions: [
{ key: 1, text: 'Navigate to page', value: 'Navigate to page' },
{ key: 2, text: 'Play speech', value: 'Play speech' }
],
selectedAction: '',
actionValue: '',
currentElement: ''
}
}
handleActionURL = (value) => {
this.setState({
actionValue: value
})
console.log(this.state.selectedAction, this.state.actionValue)
}
handleActionSpeech = (value) => {
this.setState({
actionValue: value
})
console.log(this.state.selectedAction, this.state.actionValue)
}
// Props to pass data to parent component --> NewActionSet.js
handleActionstoParent = (selected) => {
var action2Value = this.state.actionValue;
console.log(action2Value)
var action2Type = this.state.actionType
this.props.onNewAction(action2Value, action2Type)
console.log(action2Type)
// console.log(this.state.actionValue, this.state.selectedAction)
}
handleChange = (e, { value }) => {
let element
this.setState({
selectedAction: value
})
if (value === 'Navigate to page') {
element = <NewAddPageURL onNewAddPageURL={this.handleActionURL} onChange={this.handleActionstoParent()} />
} else if (value === 'Play speech') {
element = <NewSpeechText onNewSpeechText={this.handleActionSpeech} onChange={this.handleActionstoParent()} />
}
this.setState({
currentElement: element
})
}
render () {
const { value } = this.state
let index = 0
return (
<div className='action'>
<div className='container'>
<Header color='grey' as='h4'>
ACTION #{index + 1}
</Header>
<div className='row'>
<div className='col-md-4'>
<Dropdown
onChange={this.handleChange}
options={this.state.availableActions}
placeholder='Choose an action'
selection
value={value}
/>
</div>
<div className='col-md-4' />
<div className='col-md-4' />
</div>
<div style={{ marginBottom: '20px' }} />
{this.state.currentElement}
</div>
</div>
)
}
}
export default NewAction
Can you please assist?
Thanks a lot
The handleActionstoParent function in NewAction component is the problem.
When you send data from child to parent, actually the data is not updated data.
// Props to pass data to parent component --> NewActionSet.js
handleActionstoParent = (e) => {
this.setState({ [e.target.name]: e.target.value }, () => {
var action2Value = this.state.actionValue;
var action2Type = this.state.actionType;
this.props.onNewAction(action2Value, action2Type);
});
}
You could pass a function to NewAction, in example below we pass handleDataFlow function to our child component and then use it in our child component to pass data higher:
import React from 'react'
import './NewActionSet.css'
import { Header, Dropdown } from 'semantic-ui-react'
import NewSpeechText from './NewSpeechText'
import NewAddPageURL from './NewAddPageURL'
import 'bootstrap/dist/css/bootstrap.min.css'
class NewAction extends React.Component {
constructor (props) {
super(props)
this.state = {
availableActions: [
{ key: 1, text: 'Navigate to page', value: 'Navigate to page' },
{ key: 2, text: 'Play speech', value: 'Play speech' }
],
selectedAction: '',
actionValue: '',
currentElement: ''
}
}
handleActionURL = (value) => {
this.setState({
actionValue: value
})
console.log(this.state.selectedAction, this.state.actionValue)
}
handleActionSpeech = (value) => {
this.setState({
actionValue: value
})
console.log(this.state.selectedAction, this.state.actionValue)
}
// Props to pass data to parent component --> NewActionSet.js
handleActionstoParent = (selected) => {
var action2Value = this.state.actionValue;
console.log(action2Value)
var action2Type = this.state.actionType
this.props.onNewAction(action2Value, action2Type)
console.log(action2Type)
// console.log(this.state.actionValue, this.state.selectedAction)
}
handleChange = (e, { value }) => {
let element
this.setState({
selectedAction: value
})
this.props.handleDataFlow(value)
if (value === 'Navigate to page') {
element = <NewAddPageURL onNewAddPageURL={this.handleActionURL} onChange={this.handleActionstoParent()} />
} else if (value === 'Play speech') {
element = <NewSpeechText onNewSpeechText={this.handleActionSpeech} onChange={this.handleActionstoParent()} />
}
this.setState({
currentElement: element
})
}
render () {
const { value } = this.state
let index = 0
return (
<div className='action'>
<div className='container'>
<Header color='grey' as='h4'>
ACTION #{index + 1}
</Header>
<div className='row'>
<div className='col-md-4'>
<Dropdown
onChange={this.handleChange}
options={this.state.availableActions}
placeholder='Choose an action'
selection
value={value}
/>
</div>
<div className='col-md-4' />
<div className='col-md-4' />
</div>
<div style={{ marginBottom: '20px' }} />
{this.state.currentElement}
</div>
</div>
)
}
}
export default NewAction
Data flow in React is unidirectional. Data has one, and only one, way to be transferred: from parent to child.
To update parent state from child you have to send action (in props).
<NewAction updateParentState={this.doSmth} />
...
const doSmth = params => { this.setState({ ... })
and in NewAction you can call it in specific case
let parentUpdateState = ....
this.props.updateParentState(parentUpdateState);
Problem
So as the title said i've this issue in a todoapp. i checked if i had some typo like react instead of React and it seems to be alright.
Before post something i checked:
First post stackoverflow
Second post stackoverflow
but i cannot find a solution
Code
App.js
import React, {Component} from 'react';
import Form from './Components/Form';
import Footer from './Components/Footer';
import Header from './Components/Header';
class App extends React{
constructor(props) {
this.state = {
todoValue: "",
filterType: "All",
todos: [],
}
}
handleChange = (event) => {
this.setState({
todoValue: event.target.value,
})
}
handleClick = (event) => {
event.preventDefault();
if (this.state.todoValue !== "") {
const todo = {
id: Date.now(),
text: this.state.todoValue,
done: false,
}
this.setState({
todoValue: "",
todos: [todo, ...this.state.todos],
})
}
}
handleToggle = (id) => {
this.setState((prevState) => {
return {
todos: prevState.todos.map((item, i) => {
if (item.id === id) {
return {
...item,
done: !prevState.todos[i].done,
}
}
return item;
})
}
})
}
handleDelete = (id) => {
this.setState({
todos: this.state.todos.filter(item => item.id !== id)
})
}
deleteCompleted = () => {
this.setState({
todos: this.state.todos.filter(item => !item.done)
})
}
getVisibleTodos = () => {
const filterType = this.state.filterType;
let filterState = null;
switch (filterType) {
case "Completed":
return filterState = this.state.todos.filter(item => item.done);
case "Active":
return filterState = this.state.todos.filter(item => !item.done);
case "Originals":
return filterState = this.state.todos.filter(item => !item.done);
case "New":
return filterState = this.state.todos.filter(item => !item.done);
default:
return filterState = this.state.todos;
}
}
setActiveFilter = (text) => {
this.setState({
filterType: text,
})
}
render() {
return (
<div className="container">
<Header countTodo={this.state.todos.length}/>
<Form handleDelete={this.handleDelete}
handleToggle={this.handleToggle}
handleClick={this.handleClick}
handleChange={this.handleChange}
todoValue={this.state.todoValue}
todos={this.getVisibleTodos()}/>
<Footer setActiveFilter={this.setActiveFilter}
deleteCompleted={this.deleteCompleted}
filter={this.state.filterType}/>
</div>
)
}
}
export default App;
Header.js
import React from 'react';
class Header extends React.Component {
render() {
return (
<header className="header">
<h3>All To-Do {this.props.countTodo}</h3>
</header>
)
}
}
export default Header;
Form.js
import React, {Component} from'react';
import Todo from './Todo';
class Form extends React {
render() {
return (
<form className="form">
<input type="text"
className="form__input"
placeholder="Items"
onChange={this.props.handleChange}
value={this.props.todoValue}
/>
<button
className="form__button"
type="submit"
onClick={this.props.handleClick}>╋</button>
<Todo
todos={this.props.todos}
handleToggle={this.props.handleToggle}
handleDelete={this.props.handleDelete}
/>
</form>
)
}
}
export default Form;
and the last modul is Todo.js
import React, {Component} from 'react';
class Todo extends React{
render() {
return (
<ul className="todos-list">
{
this.props.todos.map((item) => {
return (
<li className="todo-item"
key={item.id} onClick={() => this.props.handleToggle(item.id)}>
<span
className={item.done ? "todo-item__name disabled" : "todo-item__name"}>
{item.text}
</span>
<span
className="todo-item__delete-button"
onClick={() => this.props.handleDelete(item.id)}>
×
</span>
</li>
)
})
}
</ul>
)
}
}
export default Todo;
You class should extend from Component that you're importing from react library.
It should be either
class App extends Component{}
or if you didn't import Component then
class App extends React.Component{}
You haven't extended your App component correctly
class App extends React{ // error here
constructor(props) {
this.state = {
todoValue: "",
filterType: "All",
todos: [],
}
}
Extend it from React.Component
class App extends React.Component {
constructor(props) {
super(props); // use super here
this.state = {
todoValue: "",
filterType: "All",
todos: [],
}
}
How to make state change from outside of class or from prop.SomeFunction () ?
I use typescript in combination. Yes i already have the class :
CLASS :
import * as React from "react";
import { Label } from "../../components/label/label";
import { TextBox } from "../../components/textBox/textBox";
import IApp from "../../interfaces/global-interfaces";
import { myStyle } from "./style";
interface HeaderI {
background: string;
myFunc(): void;
// elements: any[];
// add(id: number, content: any, event: any): void;
}
interface HeaderStateI extends IApp.ElementI {
background: string;
elements: any[];
}
export class Header extends React.Component< HeaderI, HeaderStateI , any > {
public myRef: React.RefObject<Label>;
constructor(args: any) {
super(args);
this.state = { enabledComponent : true,
visibility: true,
debugView: false,
background: args.background,
elements: [],
};
this.myRef = React.createRef();
this.add = this.add.bind(this);
console.log("state elements:" , this.state.elements);
}
public test() {
alert("Y click on header element");
}
public printMe() {
console.log("Layout Header is active :");
}
// setText = (e: React.ChangeEvent) => {
// this.setState ( { enabledComponent : true , background : (e.target as HTMLInputElement).value } );
// }
public render() {
if ( this.state.debugView === false ) {
return (
<div style={myStyle} onClick={this.addN} >
<Label name="headerName" text="i am header paragraph!" />
{this.state.elements.map((i: any) => {
return <span key={i} >{i}</span>;
})}
</div>
);
} else {
this.printMe();
return (
<div style={myStyle} >
<Label ref={this.myRef} name="headerName" text="i am header paragraph!"/>
{this.state.elements.map((i: any) => {
return <li key={i} >{i}</li>;
})}
</div>
);
}
}
public componentDidUpdate(prevProps: any) {
// Typical usage (don't forget to compare props):
console.warn("prevProps name is: " + prevProps.name);
if (this.props.background !== prevProps.background) {
this.printMe();
} else {
console.log("Background is same no update.");
}
}
public add = (id: number, content: any, event: any ) => {
this.setState(
{
elements: [React.createElement("div", { key: 2 , onclick : null }, "tyest 12")],
visibility : false,
},
);
// tslint:disable-next-line:no-unused-expression
console.log(" add from class in state elements, visible is " , this.state.visibility );
}
public addN(event: MouseEvent | Event) {
this.setState(
{
elements: [React.createElement("div", { key: 2 , onclick : null }, "tyest 12")],
visibility : false,
},
);
// tslint:disable-next-line:no-unused-expression
console.log(" add from class in state elements, visible is NNNN " , this.state.visibility );
}
}
MAIN FILE :
const AddNewElement = Services.addNewElement;
const collectMe = <Header background="#127654"/>;
ReactDOM.render(
<>
{collectMe}
<h3>Page title - inline text only example </h3>
<Title name="title" text="Hello react title" />
<Label name="root" text="I am text label component!"/> <br/>
<TextBox name="root" text="I am textBox component!"/>
</>,
document.getElementById("root"),
);
// This space is already out of class so why i can't change it ???
collectMe.props.background = "#121212";
console.log(collectMe.props);
There is lot of problem with react js.
In this post there's methods but still not working for me :
https://www.javascriptstuff.com/component-communication/#2-instance-methods
But examples are too pure with out args passing etc...
Is it react just a commercial puffed-up project.
props are read-only.
Whether you declare a component as a function or a class, it must never modify its own props.
What you need to do here is to use state. And to use state, you need to have class based component. Then, you can update the parent component state from child component using a callback function.
Take a look at this post to update the parent state from child component.
What is a point in react. We have props who's readOnly and i cant edit it and we have state also can't edit from out of class space ?!
I follow tutorials ...
if i setup {this.state.myStyle} , myStale become's readonly ?!
Here is whole class :
import * as React from "react";
import { CSSProperties } from "react";
import * as ReactDOM from "react-dom";
import { Label } from "../../components/label/label";
import IApp from "../../interfaces/global-interfaces";
import Services from "../../services/services";
import { HeaderI, HeaderStateI } from "./header-interface";
// import { myStyle } from "./style";
enum myEventList {
iNeedSomeUpdate = "i-need-some-update",
}
export class Header extends React.Component< HeaderI, HeaderStateI , any > {
public myEvent = Services.CreateEvent(myEventList.iNeedSomeUpdate, {self: this} );
public myRef: React.RefObject<HTMLDivElement>;
public myDOM: Element | Text;
private myStyle: IApp.MyMinimumCssInterface = {
display: "block",
background: "#559d96",
height: "100px",
textAlign: "center",
};
constructor(args: any) {
super(args);
this.state = { enabledComponent : true,
visibility: true,
debugView: false,
background: args.background,
elements: [],
// tslint:disable-next-line:object-literal-shorthand
myStyle: this.myStyle,
};
// e.detail.data.self..background = this.state.background;
this.myRef = React.createRef();
this.add = this.add.bind(this);
}
// Override func
public componentDidMount() {
this.myDOM = this.myRef.current;
this.myDOM.addEventListener(myEventList.iNeedSomeUpdate, this.updateOnMyEvent);
}
public updateOnMyEvent(e: CustomEvent) {
e.detail.data.self.printMe();
console.log("My custom event is done!");
e.detail.data.self.adapt();
}
public printMe() {
console.log("Layout Header is active and update is on");
}
public render() {
if ( this.state.debugView === false ) {
return (
<div ref={this.myRef} style={this.state.myStyle} onClick={this.TestEvent.bind(this)} >
<Label name="headerName" text="i am header paragraph!" />
{this.state.elements.map((i: any) => {
return <span key={i} >{i}</span>;
})}
</div>
);
} else {
this.printMe();
return (
<div style={this.state.myStyle} ref={this.myRef} >
<Label name="headerName" text="i am header paragraph!"/>
{this.state.elements.map((i: any) => {
return <li key={i} >{i}</li>;
})}
</div>
);
}
}
public componentDidUpdate(prevProps: any) {
// Typical usage (don't forget to compare props):
console.warn("prevProps name is: " + prevProps.name);
if (this.props.background !== prevProps.background) {
this.printMe();
} else {
console.log("Background is same no update.");
}
}
public add = (id: number, content: any, event: any ) => {
let localArr: any[] = [];
localArr = this.state.elements;
localArr.push(React.createElement("div", { key: id , onClick : null }, content));
this.setState(
{
elements: localArr,
visibility : false,
},
);
// tslint:disable-next-line:no-unused-expression
console.log(" add from class in state elements, visible is " , this.state.visibility );
}
public TestEvent(event: MouseEvent) {
this.add( 1 , "fffff", null);
this.add( 2 , "zzzzzz", null);
this.myDOM.dispatchEvent(this.myEvent);
}
public adapt() {
this.myStyle.background = "lime";
this.setState({
myStyle: this.myStyle,
});
}
}
Because myStyle is 'frozen', you need to clone the object, make changes and then write it back using setState.
In ES6 you can use a pattern like this:
public adapt() {
const {myStyle} = this.state
let newMyStyle = {...myStyle}
newMyStyle.background = "lime";
this.setState({
myStyle: newMyStyle,
});
}
There are several ways how to manage this i.e.
const myStyle = Object.assign({}, this.state.myStyle, { background: "lime" })
this.setState({ myStyle })