Props passing in React Native - Cheat Sheet & Quick Revision

Recall & Review

beginner

What are props in React Native?

Props are inputs to React components. They are used to pass data from a parent component to a child component, like giving instructions or information.

beginner

How do you pass a prop named title with value "Hello" to a component Greeting?

You write: <Greeting title="Hello" />. This sends the string "Hello" as the prop named title to the Greeting component.

beginner

How does a child component access props in React Native?

The child component receives props as a function argument. For example: <code>function Greeting(props) { return &lt;Text&gt;{props.title}&lt;/Text&gt;; }</code>

intermediate

Can props be changed inside the child component?

No, props are read-only. The child component should not modify props. If you want to change data, use state or pass new props from the parent.

beginner

Why is props passing important in React Native?

Props allow components to be reusable and dynamic by letting parents send different data to children. This helps build flexible and organized apps.

How do you pass a number prop named count with value 5 to a component Counter?

A <Counter count=5 />

B <Counter count={5} />

C <Counter count='5' />

D <Counter count="5" />

Numbers must be passed inside curly braces in JSX. So count={5} passes the number 5, not a string.

Where do props come from in a React Native app?

A From the parent component

B From the device hardware

C From the child component itself

D From the React Native library

Props are passed down from parent components to child components to share data.

Which of these is the correct way to access a prop named name inside a functional component?

A props.name

B this.props.name

C state.name

D name.props

In functional components, props are received as a parameter and accessed with props.name.

Can a child component modify the props it receives?

A Only if you use useEffect

B Yes, props are mutable

C Only if you use setState

D No, props are read-only

Props are read-only and should never be changed by the child component.

What happens if you pass no props to a component expecting some?

A The parent component crashes

B The app crashes

C The component uses default props or undefined values

D The component automatically creates props

If no props are passed, the component may use default props or get undefined values, depending on how it is coded.

Explain how props are passed and used in React Native components.

Think about how you tell a friend what to do and how they listen.

Describe why props passing helps make React Native apps reusable and organized.

Imagine giving different instructions to the same toy to make it do different things.