InputText: lack of the input reference when the useLayoutEffect is being executed

[mikejav]

Describe the bug

Setting the ref to the element doesn't work correctly.

If you create a new ref, assign it to the InputText component, and try to focus the input, then the error will be thrown because the element reference is not set yet.

Note: adding the ? operator will fix the issue in the dev environment (React's StrictMode) but it won't for the production build. On the production build the useLayoutEffect will be called only once when the ref is not set yet.

Reproducer

https://stackblitz.com/edit/cbt4me2u-y1z4u7vw?file=src%2FApp.jsx

System Information

System:
    OS: Windows 10 10.0.19045
    CPU: (12) x64 Intel(R) Core(TM) i5-10400F CPU @ 2.90GHz
    Memory: 13.50 GB / 31.93 GB
  Binaries:
    Node: 20.10.0 - C:\Program Files\NodeJS 20.10.0\node.EXE
    npm: 10.2.3 - C:\Program Files\NodeJS 20.10.0\npm.CMD
  Browsers:
    Edge: Chromium (131.0.2903.112)
    Internet Explorer: 11.0.19041.4355
  npmPackages:
    primereact: ^10.8.5 => 10.8.5

Steps to reproduce the behavior

1. Go to https://stackblitz.com/edit/cbt4me2u-y1z4u7vw?file=src%2FApp.jsx
2. You can see an Error thrown immediately in the console
3. Compare it with the regular HTML input: https://stackblitz.com/edit/cbt4me2u?file=src%2FApp.jsx

Expected behavior

The element's reference should be set already when executing the useLayoutEffect

[melloware]

I never use useLayoutEffect but it does work if I use useMountEffect

https://stackblitz.com/edit/cbt4me2u-saueapxw?file=src%2FApp.jsx

[melloware]

You should generally prefer useEffect over useLayoutEffect in React for the following reasons:
Performance:

• Synchronous Execution: useLayoutEffect runs synchronously, meaning it blocks the browser's painting process until the effect is complete. This can lead to performance issues, especially if the effect contains heavy computations or DOM manipulations.
• Asynchronous Execution: useEffect, on the other hand, runs asynchronously after the render cycle, allowing the browser to paint the screen first. This results in a smoother user experience, particularly in complex applications.

Server-Side Rendering (SSR):

• SSR Incompatibility: useLayoutEffect does not work with SSR, as it relies on browser-specific APIs that are not available on the server. If you are using SSR, you should use useEffect instead.

Use Cases for useEffect:

• Data Fetching: Fetching data from APIs or other external sources.
• Subscriptions: Setting up and tearing down subscriptions to external data sources.
• Manipulating the DOM (non-critical): Updating the DOM in a way that does not require immediate synchronization with the screen.

When to Use useLayoutEffect:

• DOM Measurements: If you need to measure the layout of a DOM element before the next paint, for example, to position a tooltip or dynamically adjust element sizes.
• Preventing Visual Flickering: In rare cases where you need to ensure that a certain visual effect does not flicker, you can use useLayoutEffect to synchronize updates with the browser's painting process.

Rule of Thumb:

• If your effect does not require immediate synchronization with the DOM and does not involve heavy computations, use useEffect.
• If you need to interact with the DOM in a way that affects layout or to prevent visual flickers, use useLayoutEffect sparingly and with caution.

[mikejav]

@melloware I'm not sure why comparing useEffect to useLayoutEffect here as for the regular useEffect the problem also exists. It is not relevant in the context of the bug. But thx for providing the workaround

[mikejav]

I checked the provided workaround and unfortunately, for the production build it's not working.
The elementRef.current is not initialized when the useMountEffect is executed.

@melloware pls reopen this bug.

[melloware]

@mikejav are you sure? Try this: https://stackblitz.com/edit/cbt4me2u-saueapxw?file=src%2Fmain.jsx,src%2FApp.jsx

I removed <React.StrictMode> so its running in production mode and its working the exact same for me.

[mikejav]

@melloware I'm checking it in my application in the production build. Maybe it doesn't work because of some additional compile-time optimizations and is not related to the strict mode 🤔

Workaround: I wrapped the code in the useLayoutEffect into the setTimeout but it's a dirty solution unfortunately

[melloware]

Weird there must be something else going on in your code. Because Production Mode typically means it turns Strict Mode off so hooks fire once instead of twice.