How to remove UI components using React JS - javascript

I'm having trouble finding relevant documentation on how to remove UI components when using react. For example, there's a login form. The user clicks submit and now the form should be removed from the screen. How do I do this?
I've found unmountComponentAtNode, but that can only be invoked at the parent level. Am I supposed to have a parent node that is aware of all child state and loads them conditionally? Should all children have an "isHidden" attribute which renders the dom as hidden if true?
This must be basic but I don't see this in the react js tutorials. I found this stackoverflow post (react.js: removing a component) is this really the pattern? It kind of makes sense but it means that a large app will likely have an extremely complex Application parent class that manages maps of application state based on configuration.
It seems like i need to start defining application state as named maps. For example:
BaseApp: showHeader=true;showContent=true;
LoginState: showBaseApp=true;showLoginForm=true;
LoggedInState: showBaseApp=true;showFeed=true;
At any moment we would have to update all state maps and call the base class render method...

In my opinion your question isn't about removing component but about showing the right component. And yes - it can be done with a component state but with Flux/Redux store/reducer as well.
In your example with a login form after click on "Submit" we can change local state for the component and show another text like "The request was sent blah-blah-blah" or another component.
But you can do this by extracting component's local state to a store/reducer and it'll be work better in relatively big app. Nevertheless, it's really up to you where you want to store state.

I like to use a hide prop like so.
class AppCtrlRender extends React.Component {
render() {
let page = this.state.appState.currentPage;
let hideAbout = (page != 'about');
let hideHome = (page != 'home');
return (
<div id='AppCtrlSty' style={AppCtrlSty}>
<div id='allPageSty' style={allPageSty}>
<AboutPage hide={hideAbout} />
<HomePage hide={hideHome} />
</div>
</div>
);
}
}
export default class AboutPage extends React.Component {
render() {
if (this.props.hide) return null;
let aTime = (new Cache()).time.toString();
return (
<div style={AboutPageSty}>
React 0.14 ReFlux used for app state. This is the About Page.
<NavMenu /><br/><br/>
{aTime}
</div>
);
}
}

Related

How can I add a react Component To the DOM with jquery?

This is prob a super easy question but, I want to add components to a grid with react and jquery.
gridGame is a black 100px by 100px square and I want to add items into it. Im using rows (a variable) witch is a number from 1-9 to and sumbing it in to the gridGame-${rows} as seen here,so it can auto update the correct row to join. value should be: gridGame-${row} (what ever number row is from 1-9) and then I want to add a component inside gridGame called <Test /.> (witch is declared up-top in unseen parts of the code).
The function below has jquery that I thought would work in this situation:
function = (rows) => {
console.log(`joining ${rows}`)
let value= $(`#gridGame-${rows}`);
value.append("<Test />");
value.css("background-color", 'brown');
$(".create-coinflip-box").css("display", "none");
}
The css background change works but the value.append does not display the react component.
Here is the React Component inside the <Test /.>:
import React from 'react';
import StatusIcon from './img/image.png';
import Player1Icon from './img/image.png'
class newGame extends React.Component {
render() {
return(
<div>
HELLO
</div>
);
}
}
export default newGame;
I honestly have 0 idea on how this doesn't work.
Thanks for the help :)
This answer was from David in the comments. The problem for me was I was trying to render a component through a button and not the actual render its self.
The solution is to instead make the button change the state witch Updates the React DOM. Then just have a if statement that checks the state then display the component.
His comment explains much better and fixed the problem for me.

How to preserve children state when changing parents in react?

I am new to React and working on an app that changes navbar layout and some other details according to screen size, but renders the same responsive content inside. The <MyContent /> itself can vary according to the route or tab the user is visiting.
function App() {
const isMobile = useSomeHookToDetectIfMobile();
return (
{isMobile
? <MobileWrapper><MyContent /></MobileWrapper>
: <DesktopWrapper><MyContent /></DesktopWrapper>
}
);
}
The thing is, if the user resizes the window, when changing layout all the state inside <MyContent /> is lost and reset. What would be the most React way to maintain it on resize? Keep in mind that the shape of the state of <MyContent /> can vary according to what components it is displaying, so I don't think lifting state up is the way to go. Also its state only concerns itself, so I don't think it belongs farther up the component chain. I think I am missing some key point about the problem or coming at it the wrong way. Any help would be appreciated.
In this case, a simple local variable to keep the rendered content before the condition would be enough. That way, React can keep track of it and then it's always the same instance.
function App() {
const isMobile = useSomeHookToDetectIfMobile();
const content = <MyContent />;
return (
{isMobile
? <MobileWrapper>{content}</MobileWrapper>
: <DesktopWrapper>{content}</DesktopWrapper>
}
);
}

How to force Antd to append element as child element of div React renders to instead of to HTML body?

Edit:
I figured it out & posted answer below.
Original Question
I am trying to create a completely compartmentalized web application within a shadow-dom and I've been using Antd components and ran into the issue where Antd is appending drop-down options into the body tag instead of as a child of the element that React is rendering into.
To isolate this issue I've removed everything outside of just React.render & a single Antd element which still does the same thing.
I then used a different component, "react-date-picker", which works how I had hoped Antd did, where the component renders as a child of the div specified for react.
Unfortunately, Antd rendering to the body of the HTML instead of as a child makes using shadow-root pointless.
Essentially my question is:
Is this Antd's normal functionality? If not then what might I be screwing up to have this happen? If so then is there a built-in Antd option that I'm missing that will render Antd options as child elements? If that option doesn't exist within their libraries, is there a way for me to force Antd to render as a child of my shadow-root node?
Here is what I'm using to render the Antd DatePicker component:
import ReactDOM from 'react-dom';
import React from 'react';
import DatePicker from 'antd/lib/date-picker';
ReactDOM.render(<DatePicker/>, document.getElementById('entry-fields'));
Before clicking on the Antd date picker:
After clicking on it, drop down options are appended to <body> and not <div id="entry-fields>:
Here is what I'm using to render the react-date-picker component to demonstrate the functionality I expected / need:
import ReactDOM from 'react-dom';
import React from 'react';
import DatePicker from "react-datepicker";
class Example extends React.Component {
state = {
startDate: new Date()
};
handleChange = (date: any) => {
this.setState({
startDate: date
});
};
render() {
return (
<DatePicker
selected={this.state.startDate}
onChange={this.handleChange}
/>
);
}
}
ReactDOM.render(<Example/>, document.getElementById('entry-fields'));
Before clicking on the react-date-picker date picker:
After clicking on the react-date-picker date picker (the drop down options are appended as children of the element react is rendered onto):
Basically I expected Antd to render its options encapsulated within the React rendered into <div></div> but it is instead appending elements on the <body></body>.
I'm relatively inexperienced in the web-dev domain and have resorted to asking a question here after way too much time trying to find the answer on my own. I am getting extremely frustrated in web-dev in general where any question seems to yield hundreds of irrelevant medium blog posts that are not useful in any capacity... assuming that it's not just me not knowing what to search for yet to find the answers I need which could very well be the case.
Really appreciate any help in advance.
Not sure how I managed to miss this but Antd has a parameter called "getCalendarContainer" which if left blank will render options into the body of the document but if supplied with the correct parameters will render the child elements into the container of your choosing.
Going off this example: https://react-component.github.io/calendar/examples/getCalendarContainer.html
I got it working by adding this function to my component:
getCalendarContainer()
{
return this.d || document.getElementById('calendarContainer');
}
and adding this to the component in JSX:
<div id="calendarContainer" ref={n => (this.d = n as HTMLDivElement)} >
<DatePicker onChange={EntryFields.onDateChange} getCalendarContainer={this.getCalendarContainer}/>
</div>
and initializing the div tag to reference it in the component's constructor like this:
private d: HTMLDivElement;
constructor(props: any)
{
super(props);
this.d = document.createElement("div");
...
It's also worth noting that the above will not work immediately when using shadow-DOM since you need to access the node that the shadow-DOM is a child to and then use getElementById().
Something along these lines (but probably better written I hope lol)
getContainer() {
let elem = null;
let shadowContainer = document.getElementById('entryFieldsShadow') as HTMLInputElement;
if (shadowContainer != null) {
let shadowDom = shadowContainer.firstElementChild;
if (shadowDom != null) {
let shadowRoot = shadowDom.shadowRoot;
if (shadowRoot != null) {
elem = shadowRoot.getElementById("entryFieldsContainer")
}
}
}
return elem || this.d;
}
where the JSX with react-shadow's shadow root is included looks like this:
return (
<div id="entryFieldsShadow">
<root.div>
<div>
<div id="entryFieldsContainer"/>
<style type="text/css"> #import "static/1.css"; </style>
<Layout>
<Content>
{this.RowCols()}
</Content>
</Layout>
</div>
</root.div>
</div>
)
This solve my problems
<DatePicker
{...}
getCalendarContainer={triggerNode => triggerNode.parentNode}
/>

Reuse React component from render props

I wrote a react component in render props way,it will call children function with 3 react component object ( not sure the name exactly, the variable generated by executing jsx (<div>...</div>) );
<PaginatedTable> Usage example:
<PaginationTable data={data} ...otherprops>
{({ SearchBar, Table, PaginationBar })=>
(<div>
{SearchBar}
{Table}
{PaginationBar}
</div>)
}
</PaginationTable>
with render props, I'm so glad that I can custom these 3 child component object very easily such as rearrange order or adding custom elements between these three.
{({ SearchBar, Table, PaginationBar })=>
(<div>
{PaginationBar}
<h1> my custom search bar text </h1>
{SearchBar}
{Table}
</div>)
}
But now I wish more than arrange order inside , I wish I can move {SearchBar} out of to the same layer of 's sibling 's children such as this picture.
working demo: https://codesandbox.io/s/23q6vlywy
I thought this may be anti-pattern to the unidirectional data flow of React.
Extract {SearchBar} to another independent component then use it as <SearchBar ... /> inside of <ToolBarArea /> is what I learnd from React Doc.
But in this way, I have to do "lifting state up" and write similar function and states already had in <PaginationTable /> like below **text** parts are functions and states already had in <PaginationTable />
class ToolBarArea extends Component{
render(){
return(
<div>
// text
<SearchBar onChange={**this.props.onSearchBarChange**} />
//.... other text or elements
</div>);
}
}
class ContainerArea extends Component {
state={
**searchBarText:'',**
tableData : [{...}, {...}]
}
**onSearchBarTextChange = (event)=>{
this.setState({ searchBarText: event.target.value });
}
filterdTableData = ()=> this.state.tableData.filter(d=>d.name.includes(this.state.searchBarText);
**
}
I really hope there is a way I can simply move the variable {SearchBar} in the render props function out to without knowing is in the parent or parent's sibling or anywhere in the DOM tree.
such as
<ToolBarArea>
{SearchBar} // SearchBar from <PaginationTable />
</ToolBarArea>
Is there a way to reuseonSearchBarTextChange and filtedTableData functions and these **text** codes I already wrote in <PaginationTable /> ?
I believe you hit the nail on the head when you referred to lifting state. If you already wrote a similar function then your best option may be to 'abstract' that function so that it applies to both use cases. You could use a simple flag to differentiate the unique execution each needs. Then finally pass the function down to both components.
If you're adamant about avoiding this approach you could technically get around it by using event listeners to handle data transfer or watch variables in the window but this is for sure an anti-pattern.

Show/Hide ReactJS components without losing their internal state?

I've been hiding/showing react components by not rendering them, for example:
render: function() {
var partial;
if (this.state.currentPage === 'home') {
partial = <Home />;
} else if (this.state.currentPage === 'bio') {
partial = <Bio />;
} else {
partial = <h1>Not found</h1>
}
return (
<div>
<div>I am a menu that stays here</div>
Home Bio
{partial}
</div>
);
}
but just say that the <Bio/> component has lots of internal state. Everytime I recreate the component, it loses it's internal state, and resets to it's original state.
I know of course that I could store the data for it somewhere, and pass it in via props or just globally access it, but this data doesn't really need to live outside of the component. I could also hide/show components using CSS (display:none), but I'd prefer to hide/show them as above.
What's the best practice here?
EDIT: Maybe a better way to state the problem is to use an example:
Ignore React, and assume you were just using a desktop app that had a configuration dialog with a Tab component called A, which has 2 tabs, named 1 and 2.
Say that tab A.1 has an email text field and you fill in your email address. Then you click on Tab A.2 for a second, then click back to Tab A.1. What's happened? Your email address wouldn't be there anymore, it would've been reset to nothing because the internal state wasn't stored anywhere.
Internalizing the state works as suggested in one of the answers below, but only for the component and it's immediate children. If you had components arbitrarily nested in other components, say Tabs in Tabs in Tabs, the only way for them to keep their internal state around is to either externalize it somewhere, or use the display:none approach which actually keeps all the child components around at all times.
It just seems to me that this type of data isn't data you want dirtying up your app state... or even want to even have to think about. It seems like data you should be able to control at a parent component level, and choose to either keep or discard, without using the display:none approach and without concerning yourself with details on how it's stored.
One option would be to move the conditional inside the component itself:
Bio = React.createClass({
render: function() {
if(this.props.show) {
return <p>bio comp</p>
} else {
return null;
}
}
});
<Bio show={isBioPage} />
Whether this is "best practise" or not probably depends on the exact situation.
Unfortunately, style={{display: 'none'}} trick only works on normal DOM element, not React component. I have to wrap component inside a div. So I don't have to cascade the state to subcomponent.
<div className="content">
<div className={this.state.curTab == 'securities' ? 'active' : ''}>
<Securities />
</div>
<div className={this.state.curTab == 'plugins' ? 'active' : ''}>
<Plugins />
</div>
</div>
Looks like official documentation suggests hiding stateful children with style={{display: 'none'}}
The fundamental problem here is that in React you're only allowed to mount component to its parent, which is not always the desired behavior. But how to address this issue?
I propose the solution, addressed to fix this issue. More detailed problem definition, src and examples can be found here: https://github.com/fckt/react-layer-stack#rationale
Rationale
react/react-dom comes comes with 2 basic assumptions/ideas:
every UI is hierarchical naturally. This why we have the idea of components which wrap each other
react-dom mounts (physically) child component to its parent DOM node by default
The problem is that sometimes the second property isn't what you want
in your case. Sometimes you want to mount your component into
different physical DOM node and hold logical connection between
parent and child at the same time.
Canonical example is Tooltip-like component: at some point of
development process you could find that you need to add some
description for your UI element: it'll render in fixed layer and
should know its coordinates (which are that UI element coord or
mouse coords) and at the same time it needs information whether it
needs to be shown right now or not, its content and some context from
parent components. This example shows that sometimes logical hierarchy
isn't match with the physical DOM hierarchy.
Take a look at https://github.com/fckt/react-layer-stack/blob/master/README.md#real-world-usage-example to see the concrete example which is answer to your question (take a look at the "use" property):
import { Layer, LayerContext } from 'react-layer-stack'
// ... for each `object` in array of `objects`
const modalId = 'DeleteObjectConfirmation' + objects[rowIndex].id
return (
<Cell {...props}>
// the layer definition. The content will show up in the LayerStackMountPoint when `show(modalId)` be fired in LayerContext
<Layer use={[objects[rowIndex], rowIndex]} id={modalId}> {({
hideMe, // alias for `hide(modalId)`
index } // useful to know to set zIndex, for example
, e) => // access to the arguments (click event data in this example)
<Modal onClick={ hideMe } zIndex={(index + 1) * 1000}>
<ConfirmationDialog
title={ 'Delete' }
message={ "You're about to delete to " + '"' + objects[rowIndex].name + '"' }
confirmButton={ <Button type="primary">DELETE</Button> }
onConfirm={ this.handleDeleteObject.bind(this, objects[rowIndex].name, hideMe) } // hide after confirmation
close={ hideMe } />
</Modal> }
</Layer>
// this is the toggle for Layer with `id === modalId` can be defined everywhere in the components tree
<LayerContext id={ modalId }> {({showMe}) => // showMe is alias for `show(modalId)`
<div style={styles.iconOverlay} onClick={ (e) => showMe(e) }> // additional arguments can be passed (like event)
<Icon type="trash" />
</div> }
</LayerContext>
</Cell>)
// ...

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