React Ref for sibling component

Question

I have Component named Home which contains LeftNav, BookSearch and HomeCart Component. BookSearch Component has a input field and HomeCart component has a button. When the button in HomeCart component clicked, I need to focus the input field in BookSearch Component.

I researched a bit and I could able to only focus an element from the same Component only. How can I achieve the desired behaviour this using React Ref?

Home.jsx

class Home extends React.Component {
  render() {
    return (
      <React.Fragment>
        <div className="row no-gutters app">
          <div className="col-sm-12 col-md-12 col-lg-2">
            <LeftNav />
          </div>
          <div className="col-sm-12 col-md-12 col-lg-7 books-panel">
            <BookSearch test={this.test}/>
          </div>
          <div className="col-sm-12 col-md-12 col-lg-3 cart-panel">
            <HomeCart onClick={thi} />
          </div>
        </div>
      </React.Fragment>
    );
  }
}

BookSearch.jsx

class BookSearch extends React.Component {

  render() {

    return (
      <React.Fragment>
        <button onClick={this.test}>Focus</button>
        <div className="row text-center">
          <div className="col-12">
            <form onSubmit={this.handleSubmit}>
              <h2 className="mt-5">Start searching your favorite books</h2>
              <label htmlFor="search-query" className="sr-only">
                Search by book name
              </label>
              <input
                name="search-query"
                onChange={this.handleChange}
                type="search"
                className="book-search"
                value={this.state.query}
                placeholder="Start searching...."
              />
              <button type="submit" className="btn btn-primary btn-lg">
                Search
              </button>
            </form>
          </div>
        </div>
      </React.Fragment>
    );
  }
}

HomeCart.jsx

class HomeCart extends React.Component {

  focusSearchBookInput(){
    this.props.focusSearchBookInput()
  }

  render() {
    const { cart_items } = this.props;
    const cartTable = ();
    const noCartItems = (
      <React.Fragment>
        <p>No items currently available in your cart. </p>
        <button onClick={this.focusSearchBookInput} className="btn btn-success mt-5">
          <ion-icon name="search" /> Start Searching
        </button>
      </React.Fragment>
    );
    return (
      <React.Fragment>
        <div className="row text-center">
          <div className="col-12">
            <h2 className="mt-5 mb-5">Books in your cart</h2>
            {cart_items.length > 0 ? cartTable : noCartItems}
          </div>
        </div>
      </React.Fragment>
    );
  }
}

Answer 1

One solution could be...

Create the ref and a click handler that sets focus on the ref in Home.jsx

class Home extends React.Component {
  inputRef = React.createRef();

  focusHandler = () => {
    this.inputRef.current.focus();
  }

  render() {
    return (
      <React.Fragment>
        <div className="row no-gutters app">
          <div className="col-sm-12 col-md-12 col-lg-2">
            <LeftNav />
          </div>
          <div className="col-sm-12 col-md-12 col-lg-7 books-panel">
            <BookSearch inputRef={this.inputRef} />
          </div>
          <div className="col-sm-12 col-md-12 col-lg-3 cart-panel">
            <HomeCart focusHandler={this.focusHandler} />
          </div>
        </div>
      </React.Fragment>
    );
  }
}

Add ref={this.props.inputRef} to the input in BookSearch.jsx

Add onClick={this.props.focusHandler} to the button in HomeCart.jsx