0

I got a very strange issue. I am using a ref (pointing to an image element) that is provided via react context. Unfortunately the project is quite complicated, but I will try to explain the component structure.

<ReactContext>
  <ComponentA>
    <ComponentB />
    <ComponentC>
      <imageWithRef />
    </ComponentC>
  </ComponentA>
</ReactContext>

Component a makes a network request to request the url used as the image source. The react context provides the image ref. That ref is used in several other components for calculations. Whilst component c seems to be quite happy with that ref, component b shows a very strange behavior. The function, that uses the provided ref, logs it to my browser console.

console.log({ imageRef, imageRefCurrent: imageRef.current });

// log:

{imageRef: {current: img#analysis_image.sc-hazodl.gljftv}, imageRefCurrent: undefined}

It seems to be Schrödinger's cat and I cannot find the reason for my issue.. Does anybody have an idea how to fix it?

If needed, I can provide further information.

Best wishes

Dwain
  • 43
  • 1
  • 2
  • 10
  • You may be a victim of [object logs being updated live](https://stackoverflow.com/questions/17320181/console-log-showing-only-the-updated-version-of-the-object-printed). – kelsny Oct 31 '22 at 14:55
  • 1
    Use the React devtools instead of logging to debug these kinds of issues. – kelsny Oct 31 '22 at 14:55

1 Answers1

1

That is because, when you console log a specific value of a ref, you will get the actual value at that time in the browser. But if you console log the whole reference, as you did with console logging imageRef, or even an object in your ref.current, , you are not actually getting the actual value of your ref at that time, instead you are seing how your ref looks after later mutations, which generates confusion.

My recommend is always console the value in the ref to know what's going with your on that precise moment, or if you need to console object, as caTs suggested above, console.log(json.parse(json.stringify(yourObjectInsideRef))

pepinillo6969
  • 423
  • 6
  • 15