function App() {
  return (
    <div className="App">
      <List
        renderList={({ list, isLoading }, fetch) => (
          <div>
            <button onClick={fetch}>Refresh</button>
            {isLoading && <h2>Loading...</h2>}
            <ul>
              {list.length > 0 && list.map(name => <li key={name}>{name}</li>)}
            </ul>
          </div>
        )}
      />
    </div>
  );
}