Photos reload when useEffect is called in React

Question

I have 5 photos(gifs) taken from database randomly. I have state pressedGif which defines index of photo clicked. I want to add onclick event to each of them (in a for loop):

export default function GameObject(props) {
  const addedToGameGif = [];
  const PhotoCards = [];

  const [pressedGif, gifPressed] = useState(-1);

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

  // get random photos to addedToGameGif array
  // ...

  for (let i = 0; i < addedToGameGif.length; i += 1) {
     PhotoCards.push(
      <div>
        <Card
          id={i}
          onClick={() => gifPressed(i)}>
          <img src={addedToGameGif[i]} />
        </Card>
      </div>,
    );
  }
  return <div>{PhotoCards}</div>;
 }

I get HELLO message in console successfully, but problem is that my randomly picked photos also changes to different ones. So how do I prevent that photo reloading and calling of function which picks photos randomly?

Answer 1

I would recommend something like this:

import React from 'react';

const PhotoCard = props => {
  const [addedToGameGif, setAddedToGameGif] = React.useState([]);
  const [pressedGif, setPressedGif] = React.useState(-1);
  // set random pictures
  React.useEffect(() => {
    const setRandomGifs = () => {
      let randomGifs = [];
      // make request to get random gifs
      // some loop () {
      // randomGifs.push(randomGif);
      // }
      setAddedToGameGif(randomGifs);
    };
    setRandomGifs();
  }, []);
  return (
    <>
      {addedToGameGif.map((gif, index) => {
        return (
          <Card
            id={index}
            onClick={() => setPressedGif(index)}
            key={'photo-card-' + index}
          >
            <img src={gif[index]} alt={'card-img' + index} />
          </Card>
        );
      })}
    </>
  );
};

export default PhotoCard;

If that doesn't work, check if your component gets his props changed too often from a parent, so the useEffect-Hook gets called every time that happens.