App.js

1. Imports:

   • React: To define React components and utilize React hooks like useState.
   • styled-components: For styling components with CSS-in-JS approach.
   • Axios: To make HTTP requests for fetching weather data.
   • CityComponent and WeatherComponent: Custom components for handling city input and displaying weather information.

2. WeatherIcons Object:

   • This object maps weather condition codes to corresponding icon paths.

3. Container styled-component:

   • It defines the styling for the main container of the app.

4. AppLabel styled-component:

   • This is a styled span element for displaying the label of the app.

5. CloseButton styled-component:

   • Although it’s defined, it’s not used in the current code.

6. App Component:

   • It’s a functional component named “App”.
   • Uses React’s useState hook to manage state for city and weather data.
   • Defines a fetchWeather function that makes an asynchronous call to the OpenWeatherMap API to fetch weather data based on the entered city.
   • Renders a Container component that holds either the WeatherComponent or CityComponent based on whether city and weather data are available.

index.js

1. Imports:

   • React: Required for defining React components.
   • ReactDOM: Necessary for rendering React components into the DOM.
   • ‘./index.css’: Imports the CSS file for styling.
   • App: Imports the main component of the application.

2. ReactDOM.render():

   • This function renders the root component <App /> into the DOM.
   • It’s wrapped in <React.StrictMode> for additional development mode checks and warnings.
   • The rendered component is placed inside the HTML element with the id ‘root’, which is typically a <div> element in the HTML file where the React app is mounted.

JavaScript Logic:

• useState hook is used to manage state for city and weather data.
• fetchWeather function makes an asynchronous HTTP request using Axios to fetch weather data based on the entered city.
• Conditional rendering is employed to display either the CityComponent or WeatherComponent based on the availability of city and weather data.

Purpose of Functions:

• useState: To manage state variables for city and weather data.
• fetchWeather: To fetch weather data from the OpenWeatherMap API based on the entered city.
• App Component: To render the main structure of the Weather App and manage state transitions between CityComponent and WeatherComponent.