Shuffle.js implementation with React.js - reactjs

I'm trying to activate shuffle.js component functionality (search, filter and sort) with react.js. However, the documentation on the website is very limited. I know that I need to add a search input and some buttons to do what I want, yet I'm not sure how to connect my search box input and other button events to manipulate the photogrid (or other elements within a container) that is being rendered by react.
I have imported shuffle.js as node module and initialised it on the react page. The basic code that they provide seems to be working and displays the photo grid, however, that's pretty much it. I also want to implement the search, filtering and sorting functionality but there isn't documentation on how to do that in react.js. The code below shows the photogrid implementation but nothing else.
import React, {Component} from "react";
import Shuffle from 'shufflejs';
class PhotoGrid extends React.Component {
constructor(props) {
super(props);
const grayPixel = 'data:image/gif;base64,R0lGODlhAQABAIAAAMLCwgAAACH5BAAAAAAALAAAAAABAAEAAAICRAEAOw==';
const blackPixel = 'data:image/gif;base64,R0lGODlhAQABAIAAAAUEBAAAACwAAAAAAQABAAACAkQBADs=';
const greenPixel = 'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mO02Vz4HwAE9AJhcLBN6AAAAABJRU5ErkJggg==';
this.state = {
photos: [{
id: 4,
src: grayPixel
},
{
id: 5,
src: blackPixel
},
{
id: 6,
src: greenPixel
},
],
searchTerm: '',
sortByTitle: '',
sortByDate: '',
sortByPopularity: '',
filterCategory: ''
};
this.filters = {
cat1: [],
cat2: [],
};
this.wb = this.props.dataWB;
this.element = React.createRef();
this.sizer = React.createRef();
this._handleSearchKeyup = this._handleSearchKeyup.bind(this);
this._handleSortChange = this._handleSortChange.bind(this);
this._handleCategory1Change = this._handleCategory1Change.bind(this);
this._handleCategory2Change = this._handleCategory2Change.bind(this);
this._getCurrentCat1Filters = this._getCurrentCat1Filters.bind(this);
this._getCurrentCat2Filters = this._getCurrentCat2Filters.bind(this);
}
/**
* Fake and API request for a set of images.
* #return {Promise<Object[]>} A promise which resolves with an array of objects.
*/
_fetchPhotos() {
return new Promise((resolve) => {
setTimeout(() => {
resolve([{
id: 4,
username: '#stickermule',
title:'puss',
date_created: '2003-09-01',
popularity: '233',
category1:'animal',
category2:'mammals',
name: 'Sticker Mule',
src: 'https://images.unsplash.com/photo-1484244233201-29892afe6a2c?ixlib=rb-0.3.5&q=80&fm=jpg&crop=entropy&cs=tinysrgb&w=800&h=600&fit=crop&s=14d236624576109b51e85bd5d7ebfbfc'
},
{
id: 5,
username: '#prostoroman',
date_created: '2003-09-02',
popularity: '232',
category1:'industry',
category2:'mammals',
title:'city',
name: 'Roman Logov',
src: 'https://images.unsplash.com/photo-1465414829459-d228b58caf6e?ixlib=rb-0.3.5&q=80&fm=jpg&crop=entropy&cs=tinysrgb&w=800&h=600&fit=crop&s=7a7080fc0699869b1921cb1e7047c5b3'
},
{
id: 6,
username: '#richienolan',
date_created: '2003-09-03',
popularity: '231',
title:'nature',
category1:'art',
category2:'insect',
name: 'Richard Nolan',
src: 'https://images.unsplash.com/photo-1478033394151-c931d5a4bdd6?ixlib=rb-0.3.5&q=80&fm=jpg&crop=entropy&cs=tinysrgb&w=800&h=600&fit=crop&s=3c74d594a86e26c5a319f4e17b36146e'
}
]);
}, 300);
});
}
_whenPhotosLoaded(photos) {
return Promise.all(photos.map(photo => new Promise((resolve) => {
const image = document.createElement('img');
image.src = photo.src;
if (image.naturalWidth > 0 || image.complete) {
resolve(photo);
} else {
image.onload = () => {
resolve(photo);
};
}
})));
}
_handleSortChange(evt) {
var value = evt.target.value.toLowerCase();
function sortByDate(element) {
return element.getAttribute('data-created');
}
function sortByPopularity(element) {
return element.getAttribute('data-popularity');
}
function sortByTitle(element) {
return element.getAttribute('data-title').toLowerCase();
}
let options;
if (value == 'date-created') {
options = {
reverse: true,
by: sortByDate,
};
} else if (value == 'title') {
options = {
by: sortByTitle,
};
} else if (value == 'popularity') {
options = {
reverse: true,
by: sortByPopularity,
};
} else if (value == 'default') {
this.shuffle.filter('all');
} else {
options = {};
}
this.shuffle.sort(options);
};
_getCurrentCat1Filters = function () {
return this.filters.cat1.filter(function (button) {
return button.classList.contains('active');
}).map(function (button) {
console.log('button value: '+button.getAttribute('data-value'))
return button.getAttribute('data-value');
});
};
_getCurrentCat2Filters = function () {
return this.filters.cat2.filter(function (button) {
return button.classList.contains('active');
}).map(function (button) {
console.log('button value: '+button.getAttribute('data-value'))
// console.log('button value: '+button.getAttribute('data-value'))
return button.getAttribute('data-value');
});
};
_handleCategory1Change = function (evt) {
var button = evt.currentTarget;
console.log(button)
// Treat these buttons like radio buttons where only 1 can be selected.
if (button.classList.contains('active')) {
button.classList.remove('active');
} else {
this.filters.cat1.forEach(function (btn) {
btn.classList.remove('active');
});
button.classList.add('active');
}
this.filters.cat1 = this._getCurrentCat1Filters();
console.log('current cat contains : '+this.filters.cat1);
this.filter();
};
/**
* A color button was clicked. Update filters and display.
* #param {Event} evt Click event object.
*/
_handleCategory2Change = function (evt) {
var button = evt.currentTarget;
// Treat these buttons like radio buttons where only 1 can be selected.
if (button.classList.contains('active')) {
button.classList.remove('active');
} else {
this.filters.cat2.forEach(function (btn) {
btn.classList.remove('active');
});
button.classList.add('active');
}
this.filters.cat2 = this._getCurrentCat2Filters();
console.log('current cat contains : '+this.filters.cat2);
this.filter();
};
filter = function () {
if (this.hasActiveFilters()) {
this.shuffle.filter(this.itemPassesFilters.bind(this));
} else {
this.shuffle.filter(Shuffle.ALL_ITEMS);
}
};
itemPassesFilters = function (element) {
var cat1 = this.filters.cat1;
var cat2 = this.filters.cat2;
var cat1 = element.getAttribute('data-category1');
var cat2 = element.getAttribute('data-category2');
// If there are active shape filters and this shape is not in that array.
if (cat1.length > 0 && !cat1.includes(cat1)) {
return false;
}
// If there are active color filters and this color is not in that array.
if (cat2.length > 0 && !cat2.includes(cat2)) {
return false;
}
return true;
};
/**
* If any of the arrays in the `filters` property have a length of more than zero,
* that means there is an active filter.
* #return {boolean}
*/
hasActiveFilters = function () {
return Object.keys(this.filters).some(function (key) {
return this.filters[key].length > 0;
}, this);
};
_handleSearchKeyup(event) {
this.setState({
searchTerm: event.target.value.toLowerCase()
}, () => {
this.shuffle.filter((element) => {
return element.dataset.name.toLowerCase().includes(this.state.searchTerm) || element.dataset.username.toLowerCase().includes(this.state.searchTerm);
})
})
}
componentDidMount() {
// The elements are in the DOM, initialize a shuffle instance.
this.shuffle = new Shuffle(this.element.current, {
itemSelector: '.js-item',
sizer: this.sizer.current,
});
// Kick off the network request and update the state once it returns.
this._fetchPhotos()
.then(this._whenPhotosLoaded.bind(this))
.then((photos) => {
this.setState({
photos
});
});
}
componentDidUpdate() {
// Notify shuffle to dump the elements it's currently holding and consider
// all elements matching the `itemSelector` as new.
this.shuffle.resetItems();
}
componentWillUnmount() {
// Dispose of shuffle when it will be removed from the DOM.
this.shuffle.destroy();
this.shuffle = null;
}
render() {
return (
<div>
<div id='searchBar'>
<input type="text" className='js-shuffle-search' onChange={ this._handleSearchKeyup } value={ this.state.searchTerm } />
</div>
<div id='gridActions'>
<h2>Filter By cat 1</h2>
<button onClick={ this._handleCategory1Change } value='all'>All</button>
<button onClick={ this._handleCategory1Change } value='art'>Art</button>
<button onClick={ this._handleCategory1Change } value='industry'>Industry</button>
<button onClick={ this._handleCategory1Change } value='animal'>Animal</button>
<h2>Filter By cat 2</h2>
<button onClick={ this._handleCategory2Change } value='all'>All</button>
<button onClick={ this._getCurrentCat1Filters } value='mammals'>Mammals</button>
<button onClick={ this._getCurrentCat2Filters } value='insects'>Insects</button>
<h2>Sort By</h2>
<button onClick={ this._handleSortChange } value='default'>Default</button>
<button onClick={ this._handleSortChange } value='date-created'>By Date</button>
<button onClick={ this._handleSortChange } value='title'>By Title</button>
<button onClick={ this._handleSortChange } value='popularity'>By Popularity</button>
</div>
<div ref={ this.element } id='grid' className="row my-shuffle-container shuffle"> {
this.state.photos.map(image =>
<PhotoItem { ...image } />)}
<div ref={ this.sizer } className="col-1#xs col-1#sm photo-grid__sizer"></div>
</div>
</div>
);
}
}
function PhotoItem({id, src, category1, category2, date_created, popularity, title, name, username }) {
return (
<div key={id}
className="col-lg-3 js-item"
data-name={name}
data-title={title}
data-date-created={date_created}
data-popularity={popularity}
data-category1={category1}
data-cetagory2={category2}
data-username={username}>
<img src={src} style={{width : "100%",height :"100%"}}/>
</div>
)
}
export default PhotoGrid;
The photogrid right now does nothing, just displays photos which I'm unable to search, filter and sort.

Only judging by the documentation, I haven't tried it yet, but should work.
The instance of Shuffle has a filter method, which takes a string, or an array of strings, to filter the elements by "groups", or a callback function to perform more complicated search. You should call this.shuffle.filter after updating the state of your component, i.e.:
_handleSearchKeyup(event){
this.setState({searchTerm : event.target.value}, () => {
this.shuffle.filter((element) => { /* use this.state.searchTerm to return matching elements */ } );
})
}
Edited after building a fiddle.
The callback function looks at data-name and data-username attributes to check if they contain the search string
_handleSearchKeyup(event){
this.setState({searchTerm : event.target.value.toLowerCase()}, () => {
this.shuffle.filter((element) => {
return (
element.dataset.name.toLowerCase().includes(this.state.searchTerm) ||
element.dataset.username.toLowerCase().includes(this.state.searchTerm)
);
})
})
}
For the above to work you also need to add these attributes to the DOM nodes, so update the PhotoItem component:
function PhotoItem({ id, src, name, username }) {
return (
<div key={id}
className="col-md-3 photo-item"
data-name={name}
data-username={username}>
<img src={src} style={{width : "100%",height :"100%"}}/>
</div>
)
}

In opposition to pawel's answer I think that this library operates on DOM. It makes this not react friendly.
Classic input handlers saves values within state using setState method. As an effect to state change react refreshes/updates the view (using render() method) in virtual DOM. After that react updates real DOM to be in sync with virtual one.
In this case lib manipulates on real DOM elements - calling render() (forced by setState()) will overwritte earlier changes made by Shuffle. To avoid that we should avoid using setState.
Simply save filter and sorting parameters directly within component instance (using this):
_handleSearchKeyup(event){
this.searchTerm = event.target.value;
this.shuffle.filter((element) => { /* use this.searchTerm to return matching elements */ } );
}
Initialize all the params (f.e. filterCategories, searchTerm, sortBy and sortOrder) in constructor and use them in one this.shuffle.filter() call (second parameter for sort object) on every parameter change. Prepare some helper to create combined filtering function (mix of filtering and searching), sorting is far easier.
setState can be used for clear all filters button - forced rerendering - remember to clear all parameters within handler.
UPDATE
For sorting order declare
this.reverse = true; // in constructor
this.orderBy = null;
handlers
_handleSortOrderChange = () => {
this.reverse = !this.reverse
// call common sorting function
// extracted from _handleSortChange
// this._commonSortingFunction()
}
_handleSortByChange = (evt) => {
this.orderBy = evt.target.value.toLowerCase();
// call common sorting function
// extracted from _handleSortChange
// this._commonSortingFunction()
}
_commonSortingFunction = () => {
// you can declare sorting functions in main/component scope
let options = { reverse: this.reverse }
const value = this.orderBy;
if (value == 'date-created') {
options.by = sortByDate // or this.sortByDate
} else if (value == 'title') {
options.by = sortByTitle
//...
//this.shuffle.sort(options);
You can also store ready options sorting object in component instance (this.options) updated by handlers. This value can be used by _commonSortingFunction() to call this.shuffle.sort but also by filtering functions (second parameter).
reversing button (no need to bind)
<button onClick={this._handleSortOrder}>Reverse order</button>
UPDATE 2
If you want to work with 'normal' react, setState you can move (encapsulate) all the filtering (searchBar, gridActions) into separate component.
State update will force rerendering only for 'tools', not affecting elements managed in real DOM by shuffle (parent not rerendered). This way you can avoid manual css manipulations ('active') by using conditional rendering (plus many more possibilities - list active filters separately, show order asc/desc, show reset only when sth changed etc.).
By passing this.shuffle as prop you can simply invoke search/filter/sort in parent.

Related

How to set value for the checkbox in ReactJS

I try to show my value using checkbox. Value always comes for the console log. But it didn't set for the checkbox. Here is the code and image for my problem:
var NotePage = createClass({
addTags(e) {
console.log("id****************", e.target.id);
let id = e.target.id;
let selectedTags = this.state.selectedTags;
if (selectedTags.includes(id)) {
var index = selectedTags.indexOf(id)
selectedTags.splice(index, 1);
} else {
selectedTags.push(id);
}
console.log("id****************selectedTags", selectedTags);
this.setState({
selectedTags: selectedTags
})
},
render: function () {
assignStates: function (note, token, tagCategories) {
let fields = [];
fields["title"] = note.title_en;
fields["body"] = note.body_en;
let selectedFileName = null
if (note.file_url_en != "") {
console.log("note.file_url_en ", note.file_url_en);
selectedFileName = note.file_url_en
}
let selectedTags = [];
let n = 0;
(note.note_tag).forEach(tag => {
selectedTags.push(tag.id.toString());
n++;
});
console.log("id****************first", selectedTags);
let initial_values = {
note: note,
id: note.id,
api: new Api(token),
message: "",
title: note.title_en,
body: note.body_en,
fields: fields,
isEdit: false,
selectedTags: selectedTags,
tagCategories: tagCategories,
selectedFileName: selectedFileName,
}
return initial_values;
},
const { selectedTags } = this.state;
{(tagCategory.tags).map((tag) => (
<div className="col-3">
<div>
<input
type="checkbox"
value={selectedTags.includes(tag.id)}
id={tag.id}
onChange={this.addTags} />
<label style={{ marginLeft: "10px", fontSize: "15px" }}>
{tag.name_en}
</label>
</div>
</div>
))
}
})
Image related for the problem
You've an issue with state mutation. You save a reference to the current state, mutate it, and then save it back into state. This breaks React's use of shallow reference equality checks during reconciliation to determine what needs to be flushed to the DOM.
addTags(e) {
let id = e.target.id;
let selectedTags = this.state.selectedTags; // reference to state
if (selectedTags.includes(id)) {
var index = selectedTags.indexOf(id)
selectedTags.splice(index, 1); // mutation!!
} else {
selectedTags.push(id); // mutation!!
}
this.setState({
selectedTags: selectedTags // same reference as previous state
});
},
To remedy you necessarily return a new array object reference.
addTags(e) {
const { id } = e.target;
this.setState(prevState => {
if (prevState.selectedTags.includes(id)) {
return {
selectedTags: prevState.selectedTags.filter(el => el !== id),
};
} else {
return {
selectedTags: prevState.selectedTags.concat(id),
};
}
});
},
Use the "checked" attribute.
<input
type="checkbox"
value={tag.id}
checked={selectedTags.includes(tag.id)}
id={tag.id}
onChange={this.addTags} />
also, about the value attribute in checkboxes:
A DOMString representing the value of the checkbox. This is not displayed on the client-side, but on the server this is the value given to the data submitted with the checkbox's name.
Note: If a checkbox is unchecked when its form is submitted, there is
no value submitted to the server to represent its unchecked state
(e.g. value=unchecked); the value is not submitted to the server at
all. If you wanted to submit a default value for the checkbox when it
is unchecked, you could include an inside the
form with the same name and value, generated by JavaScript perhaps.
https://developer.mozilla.org/en-US/docs/Web/HTML/Element/input/checkbox#value
I think you should use checked property instead of value.
For reference check react js docs here
You are mutating state variable directly with selectedTags.splice(index, 1); and selectedTags.push(id);
What you need to do is make a copy of the state variable and change that:
addTags(e) {
let id = e.target.id;
if (this.state.selectedTags.includes(id)) {
this.setState(state => (
{...state, selectedTags: state.selectedTags.filter(tag => tag !== id)}
))
} else {
this.setState(state => (
{...state, selectedTags: [...state.selectedTags, id]}
))
}
}

How to pass functions in Steps in antD?

code: https://codesandbox.io/s/switch-step-ant-design-demo-forked-cwcp8?file=/index.js
I have two doubts:
How do I pass functions (content1(), content2()) inside the content?
How do I restrict the Next Button, (to be performed only when a certain condition gets fulfilled in
the present page)
To your first doubt
You are returning jsx so you can render it by just doing <content1 />. I suggest make it a component outside your class component. Make it also the first letter capital:
const Content1 = ({ onClick }) => {
return (
<div>
<div>Content 1</div>
<button onClick={onClick}>Click me to go to content 2</button>
</div>
);
};
class App extends React.Component {
state = {
current: 0,
step: [
{
title: "First",
content: <Content1 onClick={() => this.click()} />
},
{
title: "Second",
content: <Content2 />
},
{
title: "Last",
content: <Content3 />
}
],
isPageOneOk: false
...
};
To your second doubt
Just track the current state on your next function and just increment the current state if a condition fulfilled:
click = () => {
alert("you can go now to content 2");
this.setState({
isPageOneOk: true
});
};
next = () => {
const {current, isPageOneOk} = this.state;
if (current === 0 && !isPageOneOk) {
alert("Can't go to next page")
} else {
//increment current state to go to next content
const current = this.state.current + 1;
this.setState({ current });
}
};
Take note that on each step, current content will unmount to the dom.
Here's the complete sample code:

How to make filter and search work together?

I have a component:
export default class Shop extends PureComponent {
state = {
search: "",
filters: [],
items: json
};
onFilterChange = ( event ) => {
const checkboxes = [...event.currentTarget.closest(".filter").getElementsByTagName("input")]
const filters = [];
checkboxes.map(checkbox => {
if (checkbox.checked) {
filters.push(checkbox.name);
}
});
this.setState({ filters }, this.filtredInput);
}
filtredInput() {
let items = json
if (this.state.filters.length !== 0) {
items = items.filter(element => this.state.filters.every(key => element[key]));
}
if (this.state.search.length !== 0) {
items = items.filter(word =>
word.name.toLocaleLowerCase().indexOf(this.state.search.toLocaleLowerCase()) !== -1
)
}
this.setState( {items} )
}
onSearchChange = ( {currentTarget} ) => {
const search = currentTarget.value
this.setState({ search }, this.filtredInput() )
}
render() {
return (
<div>
<div className="navigation">
<Filter
onFilterChange={this.onFilterChange}
/>
<Search
onSearchChange={this.onSearchChange}
/>
</div>
<Filtered
items={this.state.items}
updateShoppingBasket={this.updateShoppingBasket}
/>
</div>
)
}
}
Help to organize the logic so that both the search and the filter work simultaneously. Individually, everything works fine. But in the current version, the search works as if with a delay (apparently, the code works before the state is set), but I'm not sure that there are no other errors. How to organize the logic of the filter + search correctly in React?
You can make this much easier on yourself by thinking about the data differently. If you have it as a requirement that you always store the latest filtered data, then this won't work. I have included a custom code example here (including components that the example depends on): https://codesandbox.io/s/hardcore-cohen-sg263?file=/src/App.js
I like to think about the three pieces of data that we need to store to perform our operation.
The search term
The list of filters
The list of items we want to filter and search within
We can download the list of items from an API if we need to, and this way we can ensure we never lose data by filtering and replacing.
export default class App extends React.Component {
/*
there are three things we store
1. the current search term
2. the current list of filters
3. the entire list of data we want to search and filter through
(this can start as an empty array and then be filled with data from an API)
*/
state = {
term: "",
filters: [],
list: [
{
color: "red",
name: "car"
},
{
color: "blue",
name: "plane"
},
{
color: "red",
name: "boat"
}
]
};
/* This handles toggling filters, when the filter is clicked it will check
the array and add it if it isn't there.
*/
toggleFilter = filter => {
if (this.state.filters.includes(filter)) {
this.setState({
filters: this.state.filters.filter(item => item !== filter)
});
} else {
this.setState({
filters: [...this.state.filters, filter]
});
}
};
updateTerm = term => {
this.setState({
term
});
};
/* selector function to filter a list of items */
applyFilters = list => {
if (this.state.filters.length === 0) {
return list;
}
return list.filter(item => this.state.filters.includes(item.color));
};
/* search function to filter for the search term */
applySearch = list => {
if (this.state.term === "") {
return list;
}
return list.filter(item => item.name.startsWith(this.state.term));
};
render() {
/* we can filter the list and then search through the filtered list */
const filteredItems = this.applyFilters(this.state.list);
const searchedItems = this.applySearch(filteredItems);
/* we pass the filtered items to the list component */
return (
<>
<Filters onChange={this.toggleFilter} />
<Search term={this.state.term} onChange={this.updateTerm} />
<List items={searchedItems} />
</>
);
}
}
Hope this helps build a different mental model for React. I intentionally avoided making the Filters a controlled component, but only to show you the filter in the render function. Always open to discussion. Let me know how it goes.

How to Add filter into a todolist application in Reactjs with using .filter

im new to react, trying to make an todolist website, i have the add and delete and displaying functionality done, just trying to add an search function, but i cant seem to get it working, where as it doesn't filter properly.
i basically want to be able to filter the values on the todos.title with the search value. such as if i enter an value of "ta" it should show the todo item of "take out the trash" or any item that matches with that string.
when i try to search, it gives random outputs of items from the filtered, i am wondering if my filtering is wrong or if i am not like displaying it correctly.
ive tried to pass the value into todo.js and display it there but didn't seem that was a viable way as it it should stay within App.js.
class App extends Component {
state = {
todos: [
{
id: uuid.v4(),
title: "take out the trash",
completed: false
},
{
id: uuid.v4(),
title: "Dinner with wife",
completed: true
},
{
id: uuid.v4(),
title: "Meeting with Boss",
completed: false
}
],
filtered: []
};
// checking complete on the state
markComplete = id => {
this.setState({
todos: this.state.filtered.map(todo => {
if (todo.id === id) {
todo.completed = !todo.completed;
}
return todo;
})
});
};
//delete the item
delTodo = id => {
this.setState({
filtered: [...this.state.filtered.filter(filtered => filtered.id !== id)]
});
};
//Add item to the list
addTodo = title => {
const newTodo = {
id: uuid.v4(),
title,
comepleted: false
};
this.setState({ filtered: [...this.state.filtered, newTodo] });
};
// my attempt to do search filter on the value recieved from the search field (search):
search = (search) => {
let currentTodos = [];
let newList = [];
if (search !== "") {
currentTodos = this.state.todos;
newList = currentTodos.filter( todo => {
const lc = todo.title.toLowerCase();
const filter = search.toLowerCase();
return lc.includes(filter);
});
} else {
newList = this.state.todos;
}
this.setState({
filtered: newList
});
console.log(search);
};
componentDidMount() {
this.setState({
filtered: this.state.todos
});
}
componentWillReceiveProps(nextProps) {
this.setState({
filtered: nextProps.todos
});
}
render() {
return (
<div className="App">
<div className="container">
<Header search={this.search} />
<AddTodo addTodo={this.addTodo} />
<Todos
todos={this.state.filtered}
markComplete={this.markComplete}
delTodo={this.delTodo}
/>
</div>
</div>
);
}
}
export default App;
search value comes from the header where the value is passed through as a props. i've checked that and it works fine.
Todos.js
class Todos extends Component {
state = {
searchResults: null
}
render() {
return (
this.props.todos.map((todo) => {
return <TodoItem key={todo.id} todo = {todo}
markComplete={this.props.markComplete}
delTodo={this.props.delTodo}
/>
})
);
}
}
TodoItem.js is just the component that displays the item.
I not sure if this is enough to understand the issue 100%, i can add more if needed.
Thank you
Not sure what is wrong with your script. Looks to me it works fine when I am trying to reconstruct by using most of your logic. Please check working demo here: https://codesandbox.io/s/q9jy17p47j
Just my guess, it could be there is something wrong with your <TodoItem/> component which makes it not rendered correctly. Maybe you could try to use a primitive element such as <li> instead custom element like <TodoItem/>. The problem could be your logic of markComplete() things ( if it is doing hiding element works ).
Please let me know if I am missing something. Thanks.

ReactJS seems combine two state updates as one render, how to see separate rendering effects?

I am trying to come up a react exercise for the flip-match cards game: say 12 pairs of cards hide (face down) randomly in a 4x6 matrix, player click one-by-one to reveal the cards, when 2 cards clicked are match then the pair is found, other wise hide both again., gane over when all pairs are found.
let stored = Array(I * J).fill(null).map((e, i) => (i + 1) % (I * J));
/* and: randomize (I * J / 2) pairs position in stored */
class Board extends React.Component {
constructor() {
super();
this.state = {
cards: Array(I*J).fill(null),
nClicked: 0,
preClicked: null,
clicked: null,
};
}
handleClick(i) {
if (!this.state.cards[i]) {
this.setState((prevState) => {
const upCards = prevState.cards.slice();
upCards[i] = stored[i];
return {
cards: upCards,
nClicked: prevState.nClicked + 1,
preClicked: prevState.clicked,
clicked: i,
};
}, this.resetState);
}
}
resetState() {
const preClicked = this.state.preClicked;
const clicked = this.state.clicked;
const isEven = (this.state.nClicked-1) % 2;
const matched = (stored[preClicked] === stored[clicked]);
if (isEven && preClicked && clicked && matched) {
// this.forceUpdate(); /* no effects */
this.setState((prevState) => {
const upCards = prevState.cards.slice();
upCards[preClicked] = null;
upCards[clicked] = null;
return {
cards: upCards,
nClicked: prevState.nClicked,
preClicked: null,
clicked: null,
};
});
}
}
renderCard(i) {
return <Card key={i.toString()} value={this.state.cards[i]} onClick={() => this.handleClick(i)} />;
}
render() {
const status = 'Cards: '+ I + ' x ' + J +', # of clicked: ' + this.state.nClicked;
const cardArray = Array(I).fill(null).map(x => Array(J).fill(null));
return (
<div>
<div className="status">{status}</div>
{ cardArray.map((element_i, index_i) => (
<div key={'row'+index_i.toString()} className="board-row">
{ element_i.map((element_j, index_j) => this.renderCard(index_i*J+index_j))
}
</div>
))
}
</div>
);
}
}
Essentially, Board constructor initialize the state, and handleClick() calls setState() to update the state so it trigger the render of the clicked card's value; the callback function resetState() is that if the revealed two card did not match, then another setState() to hide both.
The problem is, the 2nd clicked card value did not show before it goes to hide. Is this due to React combine the 2 setState renderings in one, or is it rendering so fast that we can not see the first rendering effects before the card goes hide? How to solve this problem?
You're passing resetState as the callback to setState, so I would expect after the initial click your state will be reset.
You might want to simplify a bit and do something like this:
const CARDS = [
{ index: 0, name: 'Card One', matchId: 'match1' },
{ index: 1, name: 'Card Two', matchId: 'match2' },
{ index: 2, name: 'Card Three', matchId: 'match1', },
{ index: 3, name: 'Card Four', 'matchId': 'match2' },
];
class BoardSim extends React.Component {
constructor(props) {
super(props);
this.state = {
cardsInPlay: CARDS,
selectedCards: [],
checkMatch: false,
updateCards: false
};
...
}
...
componentDidUpdate(prevProps, prevState) {
if (!prevState.checkMatch && this.state.checkMatch) {
this.checkMatch();
}
if (!prevState.updateCards && this.state.updateCards) {
setTimeout(() => {
this.mounted && this.updateCards();
}, 1000);
}
}
handleCardClick(card) {
if (this.state.checkMatch) {
return;
}
if (this.state.selectedCards.length === 1) {
this.setState({ checkMatch: true });
}
this.setState({
selectedCards: this.state.selectedCards.concat([card])
});
}
checkMatch() {
if (this.selectedCardsMatch()) {
...
}
else {
...
}
setTimeout(() => {
this.mounted && this.setState({ updateCards: true });
}, 2000);
}
selectedCardsMatch() {
return this.state.selectedCards[0].matchId ===
this.state.selectedCards[1].matchId;
}
updateCards() {
let cardsInPlay = this.state.cardsInPlay;
let [ card1, card2 ] = this.state.selectedCards;
if (this.selectedCardsMatch()) {
cardsInPlay = cardsInPlay.filter((card) => {
return card.id !== card1.id && card.id !== card2.id;
});
}
this.setState({
selectedCards: [],
cardsInPlay,
updateCards: false,
checkMatch: false
});
}
render() {
return (
<div>
{this.renderCards()}
</div>
);
}
renderCards() {
return this.state.cardsInPlay.map((card) => {
return (
<div key={card.name} onClick={() => this.handleCardClick(card)}>
{card.name}
</div>
);
});
}
...
}
I've created a fiddle for this you can check out here: https://jsfiddle.net/andrewgrewell/69z2wepo/82425/

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