Passing parameters between screens in React Native - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to navigate to the Details screen with a parameter.

React Native

navigation.navigate('Details', { userId: [1] });

Drag options to blanks, or click blank then click option'

A'42'

B42

CuserId

Duser

Attempts:

3 left

💡 Hint

Common Mistakes

Passing the parameter without quotes causing a reference error.

Using a variable name that is not defined.

We pass the userId as a string inside the object when navigating.

2fill in blank

medium

Complete the code to read the parameter 'userId' from route params in the Details screen.

React Native

const { [1] } = route.params;

Drag options to blanks, or click blank then click option'

Aparams

Buser

CuserId

Did

Attempts:

3 left

💡 Hint

Common Mistakes

Using a wrong parameter name that was not passed.

Trying to access route.params.user instead of route.params.userId.

We extract 'userId' from route.params to use it in the screen.

3fill in blank

hard

Fix the error in the code to correctly pass multiple parameters when navigating.

React Native

navigation.navigate('Profile', { name: [1], age: [2] });

Drag options to blanks, or click blank then click option'

A'Alice', '30'

B'Alice'

C30

D'Alice', 30

Attempts:

3 left

💡 Hint

Common Mistakes

Passing multiple values as a single string.

Using the same blank for two different values.

Both parameters must be passed as separate key-value pairs inside the object.

4fill in blank

hard

Fill both blanks to correctly define a function that navigates with a parameter.

React Native

function goToDetails([1]) {
  navigation.[2]('Details', { itemId: 5 });
}

Drag options to blanks, or click blank then click option'

Anavigation

Bnavigate

CnavigateTo

Dnav

Attempts:

3 left

💡 Hint

Common Mistakes

Using a wrong method name like navigateTo.

Not passing the navigation object as a parameter.

The function receives the navigation object and calls its navigate method.

5fill in blank

hard

Fill all three blanks to create a button that navigates to 'Home' with a parameter 'welcome' set to true.

React Native

return (
  <Button
    title="Go Home"
    onPress={() => navigation.[1]('[2]', { [3]: true })}
  />
);

Drag options to blanks, or click blank then click option'

Anavigate

BHome

Cwelcome

Dgo

Attempts:

3 left

💡 Hint

Common Mistakes

Using a wrong method name like go.

Passing the parameter name incorrectly.

The button calls navigation.navigate to the 'Home' screen with the parameter 'welcome' set to true.

Practice

1. What is the correct way to pass a parameter named userId with value 42 when navigating to a screen called Profile in React Native?

easy

A. navigation.move('Profile', { userId })

B. navigation.goTo('Profile', userId=42)

C. navigation.push('Profile', userId=42)

D. navigation.navigate('Profile', { userId: 42 })

Solution

1. Step 1: Understand navigation method

   To pass parameters, use navigation.navigate with the screen name and an object of params.

2. Step 2: Check parameter syntax

   The parameter must be inside an object like { userId: 42 } as the second argument.

3. Final Answer:

   navigation.navigate('Profile', { userId: 42 }) -> Option D

4. Quick Check:

   Pass params with navigate(screen, { params }) [OK]

Hint: Use navigate with screen name and params object [OK]

Common Mistakes:

• Using wrong method like goTo or move
• Passing params outside an object
• Forgetting to include params argument

2. Which of the following is the correct syntax to access a parameter named itemId inside a React Native screen component?

easy

A. const itemId = props.navigation.params.itemId;

B. const itemId = navigation.route.params.itemId;

C. const itemId = route.params.itemId;

D. const itemId = params.route.itemId;

Solution

1. Step 1: Identify how params are accessed

   In React Navigation, the screen receives a route prop containing params.

2. Step 2: Use correct property chain

   Access the parameter with route.params.itemId.

3. Final Answer:

   const itemId = route.params.itemId; -> Option C

4. Quick Check:

   Use route.params to get passed parameters [OK]

Hint: Use route.params to access passed data [OK]

Common Mistakes:

• Trying to get params from navigation instead of route
• Incorrect property order like navigation.route.params
• Using props.navigation.params which is invalid

3. Given this code snippet in a React Native app:

navigation.navigate('Details', { productId: 101 });

// In Details screen component:
const Details = ({ route }) => {
  return {route.params.productId};
};

What will be displayed on the screen?

medium

A. productId

B. 101

C. route.params.productId

D. undefined

Solution

1. Step 1: Understand parameter passing

   The productId with value 101 is passed to the Details screen via navigation.navigate.

2. Step 2: Check how parameter is used in Details

   The component accesses route.params.productId and displays it inside a Text component.

3. Final Answer:

   101 -> Option B

4. Quick Check:

   Passed param value is displayed [OK]

Hint: route.params contains passed values to display [OK]

Common Mistakes:

• Expecting param name string instead of value
• Using undefined or wrong property to access param
• Not passing params correctly in navigate

4. What is wrong with this code snippet that tries to pass a parameter name to a screen called Welcome?

navigation.navigate('Welcome', name: 'Alice');

medium

A. Parameters must be passed inside an object as the second argument.

B. The screen name should be lowercase.

C. The parameter name cannot be a string.

D. navigate method does not accept parameters.

Solution

1. Step 1: Check navigate method syntax

   The second argument to navigate must be an object containing parameters.

2. Step 2: Identify error in parameter passing

   The code passes name: 'Alice' without wrapping it in curly braces, which is invalid syntax.

3. Final Answer:

   Parameters must be passed inside an object as the second argument. -> Option A

4. Quick Check:

   Params go inside an object in navigate [OK]

Hint: Always wrap params in an object when navigating [OK]

Common Mistakes:

• Passing params without curly braces
• Using wrong syntax for navigate arguments
• Assuming screen names must be lowercase

5. You want to navigate from a Home screen to a Profile screen and pass both userId and userName. How should you write the navigation call to pass these parameters correctly?

hard

A. navigation.navigate('Profile', { userId: 5, userName: 'John' })

B. navigation.navigate('Profile', userId=5, userName='John')

C. navigation.navigate('Profile', ['userId', 5, 'userName', 'John'])

D. navigation.navigate('Profile', { 'userId': 5 }, { 'userName': 'John' })

Solution

1. Step 1: Understand parameter object structure

   Multiple parameters must be passed inside a single object with key-value pairs.

2. Step 2: Check each option's syntax

   navigation.navigate('Profile', { userId: 5, userName: 'John' }) correctly passes both userId and userName inside one object.

3. Final Answer:

   navigation.navigate('Profile', { userId: 5, userName: 'John' }) -> Option A

4. Quick Check:

   Pass multiple params inside one object [OK]

Hint: Put all params inside one object in navigate call [OK]

Common Mistakes:

• Passing params as separate arguments
• Using array instead of object for params
• Splitting params into multiple objects