javascript - useState react hook does not set the array state - Stack Overflow

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I am trying to set the videos state to the items array of the response from the api but when I console.log the videos it returns an empty array.... Here is the code to fetch the api in which I set the videos state

const [videos, setVideos] = useState([]);
const handleFormSubmit = async (searchterm) => {
    await fetch(
      `?${params.toString()}&q=${searchterm}`
    )
      .then((response) => response.json())
      .then((data) => {
        console.log(data);
        setVideos(data.items);
        console.log(videos);
      });
  };

How do I set the items array to the videos state?

I am trying to set the videos state to the items array of the response from the api but when I console.log the videos it returns an empty array.... Here is the code to fetch the api in which I set the videos state

const [videos, setVideos] = useState([]);
const handleFormSubmit = async (searchterm) => {
    await fetch(
      `https://www.googleapis./youtube/v3/search?${params.toString()}&q=${searchterm}`
    )
      .then((response) => response.json())
      .then((data) => {
        console.log(data);
        setVideos(data.items);
        console.log(videos);
      });
  };

How do I set the items array to the videos state?

• javascript
• reactjs
• react-hooks

Share Improve this question Follow asked Aug 12, 2020 at 10:53 prem kulkarniprem kulkarni 2933 bronze badges 3

• 1 setVideos is not a synchronous operation, the videos array will change the next time the functional ponent is rendered. – Rustam D9RS Commented Aug 12, 2020 at 10:57
• You can't log updated state right after calling setVideos. Your state is getting updated, your ponent will have to re-render to see the updated state. Also make sure you have a catch block to catch and handle any errors that might occur during the request. – Yousaf Commented Aug 12, 2020 at 11:00
• Not related to your problem but either use async-await syntax or promise chaining, don't mix both of them. – Yousaf Commented Aug 12, 2020 at 11:08

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3 Answers 3

Sorted by: Reset to default 7

Ciao, unfortunately with hooks you cannot log videos after setVideos call because setVideos is async.

To get the last value of videos you have to use useEffect hook in this way:

useEffect(() => {
   console.log(videos);
}, [videos]);

TLDR

React Hooks work async setState -> render -> state binding

Answer

react hooks is working like that

1. setState
2. schedule render ponent ( I mean state changed ponent)
3. and render with changed state

So, You couldn't access video at that console.log(video)

Reference

1. Overreact
2. My medium with korean (You can translate with google)
3. How does React Hooks re-renders a function Component?

You are using async/await, so it should be

const [videos, setVideos] = useState([])
const handleFormSubmit = async (searchterm) => {
  const response = await fetch(
    `https://www.googleapis./youtube/v3/search?${params.toString()}&q=${searchterm}`
  )
  const data = await response.json()
  console.log(data)
  setVideos(data.items)
  console.log(videos)
}

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