[React] Manipulate the DOM with React refs

React is really good at creating and updating DOM elements, but sometimes you need to work with them yourself. A common use case for this is when you’re using a third party library that wasn’t built for or with React specifically. To do this, we need to have some value that’s associated with our component (like state) to store a reference to the DOM element, but doesn’t trigger re-renders when it’s updated (unlike state). React has something specifically for this and it’s called a ref.

You create a ref object with the useRef hook and that object’s current property is the current value of the ref. It can be anything, but if you pass that ref object to a component as a prop called ref, then React will set the current property to the DOM element it creates so you can reference it and manipulate it in your useEffect hook.

In this lesson we’ll get to see how that works with a cool library called vanilla-tilt.

function Tilt({ children }) {
      const tiltRef = React.useRef();

      // refs provide a way to access DOM nodes or React elements created in the render method.
      // we need to access DOM thought ref, so we need to render the DOM first, useEffect hook 
      // is the prefect place to do it.

      React.useEffect(() => {
        // useRef returns a mutable ref object whose .current property is initialized to the passed argument (initialValue).
        const tiltNode = tiltRef.current;
        // The returned object will persist for the full lifetime of the component.
        const vanillaTiltOptions = {
          max: 25,
          speed: 400,
          glare: true,
          'max-glare': 0.5
        };
        // Initiating VanillaTilt and passing tiltNode and vanillaTiltOptions
        VanillaTilt.init(tiltNode, vanillaTiltOptions);
        return () => {
          // ensuring that any node refs in memory get garbage collected
          // prevent memory leaks
          tiltNode.vanillaTilt.destroy();
        };
        // adding a dependencies array, to avoid multiple renders
      }, []);

      return (
        // Referencing the useEffect hook return
        <div ref={tiltRef} className="tilt-root">
          <div className="tilt-child">{children}</div>
        </div>
      );
    }