How to load data before rendering in React?

Question

React

Hello, is there any way to load data from the Rest API before the render is executed, I tried to do it using componentDidMount, but the data is loaded a little later, i.e. the page is empty for a few seconds after loading, how can I deal with this problem?

Answer 1

`componentDidMount` fires after `render`, you can show preloader while data is loading, show data after loading

class example extends React.Component {
  state = {
    data: [],
    isLoading: true,
  }

  componentDidMount() {
    fetch('example/url')
      .then(response => response.json())
      .then(data => this.setState({ data }))
  }

  render() {
    const { isLoading } = this.state

    if (isLoading) {
      return <div>Загрузка</div>
    }

    return data.map(item => <div key={item.id}>{item.name}</div>)
  }
}