beginners-guide-to-react-base/23-rendering-lists.html at main · volta2016/beginners-guide-to-react-base · GitHub

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<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>23-rendering-lists</title>
  </head>
  <style>
    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen,
        Ubuntu, Cantarell, "Open Sans", "Helvetica Neue", sans-serif;
    }
  </style>
  <body>
    <div id="root"></div>

    <script
      src="https://unpkg.com/react@17/umd/react.production.min.js"
      crossorigin
    ></script>
    <script
      src="https://unpkg.com/react-dom@17/umd/react-dom.production.min.js"
      crossorigin
    ></script>
    <script src="https://unpkg.com/@babel/standalone/babel.min.js"></script>

    <script type="text/babel">
      const allItems = [
        { id: "a", value: "apple" },
        { id: "o", value: "orange" },
        { id: "g", value: "grape" },
        { id: "p", value: "pear" },
      ];

      function App() {
        const [items, setItems] = React.useState(allItems);

        function addItem() {
          setItems([...items, allItems.find((i) => !items.includes(i))]);
        }

        function removeItem(item) {
          setItems(items.filter((i) => i !== item));
        }

        return (
          <div>
            <button
              disabled={items.length >= allItems.length}
              onClick={addItem}
            >
              add item
            </button>
            <ul style={{ listStyle: "none", paddingLeft: 0 }}>
              {items.map((item) => (
                <li key={item.id}>
                  <button onClick={() => removeItem(item)}>remove</button>{" "}
                  <label htmlFor={`${item.value}-input`}>{item.value}</label>{" "}
                  <input id={`${item.value}-input`} defaultValue={item.value} />
                </li>
              ))}
            </ul>
          </div>
        );
      }

      ReactDOM.render(<App />, document.getElementById("root"));
    </script>
  </body>
</html>