Passing useState data from one functional component to another - reactjs

Question

I have two function components with useState in two different files in my project. I want to display the url on my FaceRecognition component if I set fetchSuccess to true.
const ImageLinkForm = () => {
const [url, setUrl] = useState("");
const [fetchSuccess, setFetchSuccess] = useState(false);
const onInputChange = (event) => {
// I get the url and fetchSuccess is true
};
return (
<div>
// I return a form that allowed me to make the fetch call
</div>
);
};
export default ImageLinkForm;
const FaceRecognition = () => {
return (
<div>
{/* if fetchSuccess */}
<img src=url />
</div>
);
};
export default FaceRecognition;

Answer 1

This really depends on how these components are hierarchically related but one easy-ish option is to use the context API
// context/image.js
import { createContext, useState } from "react";
export const ImageContext = createContext({ fetchSuccess: false });
export const ImageContextProvider = ({ children }) => {
const [fetchSuccess, setFetchSuccess] = useState(false);
const setSuccessful = () => {
setFetchSuccess(true);
};
return (
<ImageContext.Provider value={{ fetchSuccess, setSuccessful }}>
{children}
</ImageContext.Provider>
);
};
Your components can then use the context to read the value...
import { useContext } from "react";
import { ImageContext } from "path/to/context/image";
const FaceRecognition = () => {
const { fetchSuccess } = useContext(ImageContext);
return <div>{fetchSuccess && <img src="url" />}</div>;
};
and write the value...
import { useContext, useState } from "react";
import { ImageContext } from "path/to/context/image";
const ImageLinkForm = () => {
const [url, setUrl] = useState("");
const { setSuccessful } = useContext(ImageContext);
const onInputChange = (event) => {
// I get the url and fetchSuccess is true
setSuccessful();
};
return (
<div>{/* I return a form that allowed me to make the fetch call */}</div>
);
};
The only thing you need to do is wrap both these components somewhere in the hierarchy with the provider
import { ImageContextProvider } from "path/to/context/image";
const SomeParent = () => (
<ImageContextProvider>
<ImageLinkForm />
<FaceRecognition />
</ImageContextProvider>
);