Course Content

React Tutorial

1. Getting Started

What is React?What is a Component?Virtual DOM JSX render()constructor()State and setState()Props (properties)Binding Methods Challenge

2. Lifecycle Methods

componentWillMount()componentWillUnmount()componentDidMount()shouldComponentUpdate()componentDidUpdate()componentDidCatch()Overview of Component Lifecycle Challenge

3. Functional Components and Hooks

Syntax What is a Hook?useState() useEffect()useMemo()useRef()Challenge

4. Advanced Topics

Context API Consumer Provider useContext()useReducer()React Router Dom Link Component

useContext()

useContext is a hook in the React Context API that allows you to consume the context value in a functional component. It works by taking a context object as an argument and returning the current context value for that context.

Here's an example of how you might use useContext to consume the context value in a functional component:

In this example, the ThemeTogglerButton functional component is able to consume the theme and toggleTheme values from the ThemeContext without having to pass them down as props. It does this by using the useContext hook and passing the ThemeContext object as an argument. The hook returns the current context value for the ThemeContext, which can then be destructured and used within the component.

One advantage of using useContext is that it allows you to avoid the nesting and rendering overhead of the Consumer component. This can make your code simpler and more performant, especially if you have a deeply nested component tree that needs to access the context value.

1. How is a context object created in the react-context API?

2. When should the useContext hook be used in the react-context API?

3. Fill in the given code:

4. When should you use the Context API instead of props for sharing state?

5. What is the createContext function used for in the Context API?

How is a context object created in the react-context API?

Select the correct answer

By wrapping a component with the Consumer component

By wrapping a component with the Provider component

By calling the createContext function

By calling the useContext hook

When should the useContext hook be used in the react-context API?

Select the correct answer

Consuming the value of a context object within a functional component

Providing context to a functional component

Creating a context object that can be shared by multiple components

Updating the state of a component

Fill in the given code:

const AuthContext = React.({
authenticated: false,
login: () => {},
logout: () => {}
});

class AuthProvider extends React.{}

Click or drag`n`drop items and fill in the blanks

When should you use the Context API instead of props for sharing state?

Select the correct answer

When the state needs to be shared by many components

When the state needs to be deeply nested in the component tree

When the state needs to be mutable

All of the above

What is the createContext function used for in the Context API?

Select the correct answer

To create a new context object

To create a context provider component

To create a context consumer component

All of the above

Everything was clear?

Section 4. Chapter 4

Course Content

React Tutorial

1. Getting Started

What is React?What is a Component?Virtual DOM JSX render()constructor()State and setState()Props (properties)Binding Methods Challenge

2. Lifecycle Methods

componentWillMount()componentWillUnmount()componentDidMount()shouldComponentUpdate()componentDidUpdate()componentDidCatch()Overview of Component Lifecycle Challenge

3. Functional Components and Hooks

Syntax What is a Hook?useState() useEffect()useMemo()useRef()Challenge

4. Advanced Topics

Context API Consumer Provider useContext()useReducer()React Router Dom Link Component

useContext()

Here's an example of how you might use useContext to consume the context value in a functional component:

1. How is a context object created in the react-context API?

2. When should the useContext hook be used in the react-context API?

3. Fill in the given code:

4. When should you use the Context API instead of props for sharing state?

5. What is the createContext function used for in the Context API?

How is a context object created in the react-context API?

Select the correct answer

By wrapping a component with the Consumer component

By wrapping a component with the Provider component

By calling the createContext function

By calling the useContext hook

When should the useContext hook be used in the react-context API?

Select the correct answer

Consuming the value of a context object within a functional component

Providing context to a functional component

Creating a context object that can be shared by multiple components

Updating the state of a component

Fill in the given code:

const AuthContext = React.({
authenticated: false,
login: () => {},
logout: () => {}
});

class AuthProvider extends React.{}

Click or drag`n`drop items and fill in the blanks

When should you use the Context API instead of props for sharing state?

Select the correct answer

When the state needs to be shared by many components

When the state needs to be deeply nested in the component tree

When the state needs to be mutable

All of the above

What is the createContext function used for in the Context API?

Select the correct answer

To create a new context object

To create a context provider component

To create a context consumer component

All of the above

Everything was clear?

Section 4. Chapter 4