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react hooks useEffect update window.innerHeight

I want to update state with the inner window height as I resize the screen. When I log the state height within the useEffect hook I get 0 each time however, when I log inside the updateWindowDimensions function the height value is updated as expected.

How can I update state with the new value each time?

const [height, setHeight] = useState(0);

const updateWindowDimensions = () => {
    const newHeight = window.innerHeight;
    setHeight(newHeight);
    console.log('updating height');   
};

 useEffect(() => {
     window.addEventListener('resize', updateWindowDimensions);
     console.log("give height", height);
 }, []);
like image 543
Filth Avatar asked Jan 26 '23 06:01

Filth


1 Answers

Your useEffect is only being run one time, when the component mounts (because of the empty array [] you passed as the second argument)

If you simply log outside of it, you'll see your state value is being updated correctly

  const [height, setHeight] = useState(0);

  useEffect(() => {
    const updateWindowDimensions = () => {
      const newHeight = window.innerHeight;
      setHeight(newHeight);
      console.log("updating height");
    };

    window.addEventListener("resize", updateWindowDimensions);

    return () => window.removeEventListener("resize", updateWindowDimensions) 

  }, []);

  console.log("give height", height);

Also you should move the declaration of that function inside the useEffect so it's not redeclared on every render

like image 179
Galupuf Avatar answered Jan 27 '23 18:01

Galupuf