To build a React app, do I need to build the entire app first?

Question

React

Is it necessary before creating an application, first to make the whole layout, and then "implant" it on the recat?
How does this process take place in a real project?

Answer 1

No, it will be double work. In a real project, a programmer:
1. Describes the component
2. Writes JSX markup in render
3. Styles the component, depending on the selected technology
4. Writes the necessary methods and listeners