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Changing the value of a react input component with JS doesn't fire the inputs onChange event

I have a range input that has a few things happening onChange. This works as I'd expect with manual click/drag usage. However, when I try to change the value with JavaScript, my onChange event doesn't seem to fire.
Here is my code:
const App = () => {
const [currentValue, setCurrentValue] = useState(0);
const setRangeValue = () => {
const range = document.querySelector("input");
range.value = 50;
range.dispatchEvent(new Event("change", { bubbles: true }));
};
return (
<div className="App">
<h1>Current Value: {currentValue}</h1>
<input
type="range"
min={0}
max={100}
step={10}
onChange={e => {
console.log("Change!");
setCurrentValue(+e.target.value);
}}
defaultValue={0}
/>
<button onClick={setRangeValue}>Set current value to 50</button>
</div>
);
};
And here it is (not) working in CodeSandbox:
https://codesandbox.io/s/divine-resonance-rps1n
NOTE:
Just to clarify. My actual issue comes from testing my component with jest/react testing library. The button demo is just a nice way to visualize the problem without getting into the weeds of having to duplicate all of my test stuff too.
const getMessage = (value, message) => {
const slider = getByRole('slider');
fireEvent.change(slider, { target: { value } });
slider.dispatchEvent(new Event('change', { bubbles: true }));
return getByText(message).innerHTML;
};
When the fireEvent changes the value, it doesn't run the onChange events attached to the input. Which means that getByText(message).innerHTML is incorrect, as that will only update when a set hook gets called onChange. (All of this works when manually clicking/dragging the input slider, I just can't "test" it)
Any help would be great!

The issue is that React has a virtual DOM which doesn't connect directly to the DOM. Note how the events from React are SyntheticEvents. They are not the actual event from the DOM.
https://github.com/facebook/react/issues/1152
If this is for a unit test, create a separate component for the slider and text and make sure they perform as expected separate from each other with props.
For a more in-depth article on how to specifically test a range slider, checkout https://blog.bitsrc.io/build-and-test-sliders-with-react-hooks-38aaa9422772
Best of luck to ya!

React - problems with useState and Firebase

I was trying to resolve this problem, but I have no luck...
I'm using React and 'react-bootstrap'. Getting data from firebase with useState, as you can see in the next code. But also I'm calling a modal as a component, and this modal use useState to show and hide the modal.
export const Models = () => {
const [models, setModels] = useState(null);
useEffect(() => {
firebase.database().ref('Models').on('value', (snapshot) => {
setModels(snapshot.val())
});
}, []);
return models;
}
the problem result when I click on the url to access the modal, this one is shown and the main component goes to firebase and tries to get the data again. So, if I click 3 times on the modal, I will get my data from firebase 3 times.
How can I fix this? to get my data from firebase only one time, regardless of the times that you open the modal window?
The other part of the code
const Gallery = () => {
const [fireBaseDate, setFireBaseDate] = useState(null);
axios.post('https://us-central1-models-gallery-puq.cloudfunctions.net/date',{format:'DD/MM/YYYY'})
.then((response) => {
setFireBaseDate(response.data)
});
let content = Models();
let models = [];
const [imageModalShow, setImageModalShow] = useState(false);
const [selectedModel, setSelectedModel] = useState('');
if(content){
Object.keys(content).map((key, index) =>
models[index] = content[key]
);
models = shuffleArray(models);
console.log(models)
return(
<div className="appContentBody">
<Jumbo />
<Promotion models={models}/>
<div className="Gallery">
<h1>Galería - Under Patagonia</h1>
<Filter />
<div className="img-area">
{models.map((model, key) =>{
let myDate = new Date(model.creationDate);
let modelEndDate = new Date(myDate.setDate(myDate.getDate() + 30)).toLocaleDateString('en-GB')
if(fireBaseDate !== modelEndDate && model.active === true){
return (
<div className="img-card filterCard" key={key}>
<div className="flip-img">
<div className="flip-img-inner">
<div className="flip-img-front">
<img className="single-img card-img-top" src={model.thumbnail} alt="Model"/>
</div>
<div className="flip-img-back">
<h2>{model.certified ? 'Verificada!' : 'No Verificada'}</h2>
<p>Número: {model.contact_number}</p>
<p>Ciudad: {model.city}</p>
<p>Servicios: {model.services}</p>
</div>
</div>
</div>
<h5>{model.name}</h5>
<Button variant="danger" onClick={() => {
setImageModalShow(true)
setSelectedModel(model)}
}>
Ver
</Button>
</div>
);
}
return 0})}
</div>
<Image
show={imageModalShow}
onHide={() => setImageModalShow(false)}
model={selectedModel}
/>
</div>
<Footer />
</div>
)} else {
return (
<div className="loading">
<h1>Loading...</h1>
</div>
)}
}
export default Gallery;
Thanks for your time!

Models is a regular javascript function, not a functional component. So this is not a valid use of hooks, and will not work as expected. See docs on rules of hooks.
A functional component receives props and returns JSX or another React element.
Since it does not, it is basically restarting and calling your effect each time its called by the parent.
Looking at your edit, you should probably just remove the Models function and put the logic in the Gallery component.

The way I read your above component makes it seem like you've defined a custom hook for getting data from firebase.
So first off, I would rename it to useFbData and treat it as a custom hook, so that you can make use of the ESLint Plugin for Hooks and make sure you're following the rules of hooks.
The way you have this above, if it's a function within a component, your function will fire on every render, so the behaviour you are describing is what I would expect.
Depending on how expensive your request is/how often that component renders, this might be what you want, as you probably don't want to return stale data to your component. However, if you feel like the response from the DB should be cached and you have some logic to invalidate that data you could try something like this:
import { useEffect, useRef } from 'react';
const useFbData = invalidationFlag => {
const data = useRef(null);
useEffect(() => {
if (!data.current || invalidationFlag) {
firebase.database().ref('Data').on('value', (snapshot) => {
data.current = snapshot.val();
});
}
}, [invalidationFlag]);
return data.current;
};
export default useFbData;
This way, on the initial run and every time you changed the value of invalidationFlag, your effect inside the useFbData hook would run. Provided you keep track of invalidationFlag and set it as required, this could work out for you.
The reason I used a ref here instead of state, is so that the effect hook doesn't take the data in the dependency array (which would cause it to loop indefinitely if we used state).
This will persist the result of the db response between each call and prevent the call being made multiple times until you invalidate. Remember though, this will mean the data you're using is stale until you invalidate.

React: set width of a div to be the width of an image

I want to make the width of my div be the same width as my image. This includes when you resize the window and the image auto resize. Currently, I tried using useState, but it does not respond when resize.
const basicInfoImage = useRef();
const basicInfoText = useRef();
const [basicInfoImageWidth, setBasicInfoImageWidth] = useState();
useEffect(() => {
setBasicInfoImageWidth(
basicInfoImage.current.getBoundingClientRect().width
);
});
<img
src={profilePic}
alt="Profile Pic"
className="About-basic-info-image"
ref={basicInfoImage}
/>
<p
className="About-basic-info-text"
ref={basicInfoText}
style={{ width: basicInfoImageWidth }}
>
{basicInfoTextContent}
</p>

The way you're using useEffect right now it will only run once when the component mounts. You'll have to add an event listener to the resize event and then call the setBasicInfoImageWidth
useEffect(() => {
window.addEventListener('resize', () => setBasicInfoImageWidth(
basicInfoImage.current.getBoundingClientRect().width
));
});
It would probably be simpler to solve this using CSS, although without a working example it would be hard to give you a working snippet. If you add a jsfiddle link I'll be happy to help you out with the CSS

You can do it with CSS, no need to use react State

What does the .current property of the querySelector method refer to?

I came across this line of code via a snippet on https://usehooks.com,
document.querySelector('body').current
I haven't been able to find .current in the specification at all.
I was hoping someone could clarify its purpose in this context.
It's being used within the IntersectionObserver API in the full example (below) - perhaps the API is exposing the property?
Any help is much appreciated. Thanks in advance.
Following is the full source code:
import { useState, useEffect, useRef } from 'react';
// Usage
function App() {
// Ref for the element that we want to detect whether on screen
const ref = useRef();
// Call the hook passing in ref and root margin
// In this case it would only be considered onScreen if more ...
// ... than 300px of element is visible.
const onScreen = useOnScreen(ref, '-300px');
return (
<div>
<div style={{ height: '100vh' }}>
<h1>Scroll down to next section 👇</h1>
</div>
<div
ref={ref}
style={{
height: '100vh',
backgroundColor: onScreen ? '#23cebd' : '#efefef'
}}
>
{onScreen ? (
<div>
<h1>Hey I'm on the screen</h1>
<img src="https://i.giphy.com/media/ASd0Ukj0y3qMM/giphy.gif" />
</div>
) : (
<h1>Scroll down 300px from the top of this section 👇</h1>
)}
</div>
</div>
);
}
// Hook
function useOnScreen(ref, margin = '0px') {
// State and setter for storing whether element is visible
const [isIntersecting, setIntersecting] = useState(false);
useEffect(() => {
const observer = new IntersectionObserver(
([entry]) => {
// Update our state when observer callback fires
setIntersecting(entry.isIntersecting);
},
{
rootMargin: margin,
root: document.querySelector('body').current
}
);
if (ref.current) {
observer.observe(ref.current);
}
return () => {
observer.unobserve(ref.current);
};
}, []); // Empty array ensures that effect is only run on mount and unmount
return isIntersecting;
}

document.querySelector('body').current is just a property of the body element, which has nothing to do with document.querySelector. It may have been set somewhere else as it is not an existing property of the body element.
var body = document.querySelector("body");
console.log("body.current:", "body.current");
body.current = "SOMEVALUE";
console.log("After setting body.current");
console.log("body.current:", "body.current");

Sorry to disappoint, but it doesn't do anything. It's just a way to supply undefined to the IntersectionObserver API. If you replace document.querySelector('body').current with undefined or remove the entire root field altogether, you still get the same result.
I removed that field to test it to verify the same behavior. Try it yourself in the Codesandbox link here.
As seen by this comment on the example, it can be removed entirely:
You can remove root entirely, since it defaults to the viewport anyway (also document.querySelector('body').current is always undefined, could be document.body but isn't needed anyway)

Get React.refs DOM node width after render and trigger a re-render only if width has value has changed

I'm attempting to get the width of a ref DOM element and set state to then use within the Component render. The problem comes because this width changes on user input and when I try setState within componentDidUpdate it starts an infinite loop and my browsers bombs.
I created a fiddle here http://jsbin.com/dizomohaso/1/edit?js,output (open the console for some information)
My thinking was;
Component Mounts, setState: refs.element.clientWidth
User inputs data, triggers render
shouldComponentUpdate returns true only if new.state is not equal to old.state. My problem is, I'm not sure where makes sense to update this state?
Any help will be much appreciated, thanks for reading!
Brad.

var component = React.createClass({
componentDidMount: function() {
//Get initial width. Obviously, this will trigger a render,
//but nothing will change, look wise.
//But, if this is against personal taste then store this property
//in a different way
//But it'll complicate your determineWidth logic a bit.
this.setState({
elWidth: ReactDOM.findDOMNode(this.refs.the_input).getBoundingClientRect().width
})
},
determineWidth: function() {
var elWidth = ReactDOM.findDOMNode(this.refs.the_input).getBoundingClientRect().width
if (this.state.elWidth && this.state.elWidth !== elWidth) {
this.setState({
elWidth: elWidth
})
}
},
render: function() {
var styleProp = {}
if (this.state.elWidth) {
styleProp.style = { width: this.state.elWidth };
}
return (
<input ref="the_input" onChange={this.determineWidth} {...styleProp} />
)
}
})
I like to use .getBoundingClientRect().width because depending on your browser, the element might have a fractional width, and that width will return without any rounding.