Stack Navigator in React Native - Mini App: Build & Ship

Build: Simple Stack Navigation

Build a two-screen app using stack navigation. The first screen has a button to go to the second screen. The second screen has a button to go back.

Target UI

Screen 1:
+---------------------+
|    Home Screen      |
|                     |
|  [Go to Details]    |
+---------------------+

Screen 2:
+---------------------+
|   Details Screen    |
|                     |
|  [Go Back]          |
+---------------------+

Use React Navigation stack navigator

Screen 1 named 'Home' with a button labeled 'Go to Details'

Screen 2 named 'Details' with a button labeled 'Go Back'

Pressing 'Go to Details' navigates to Details screen

Pressing 'Go Back' returns to Home screen

Starter Code

React Native

import * as React from 'react';
import { Button, View, Text } from 'react-native';
import { NavigationContainer } from '@react-navigation/native';
import { createNativeStackNavigator } from '@react-navigation/native-stack';

const Stack = createNativeStackNavigator();

function HomeScreen({ navigation }) {
  return (
    <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
      {/* TODO: Add a button to navigate to Details screen */}
    </View>
  );
}

function DetailsScreen({ navigation }) {
  return (
    <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
      {/* TODO: Add a button to go back to Home screen */}
    </View>
  );
}

export default function App() {
  return (
    <NavigationContainer>
      <Stack.Navigator>
        {/* TODO: Add Home and Details screens here */}
      </Stack.Navigator>
    </NavigationContainer>
  );
}

Task 1

Task 2

Task 3

Solution

React Native

import * as React from 'react';
import { Button, View, Text } from 'react-native';
import { NavigationContainer } from '@react-navigation/native';
import { createNativeStackNavigator } from '@react-navigation/native-stack';

const Stack = createNativeStackNavigator();

function HomeScreen({ navigation }) {
  return (
    <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
      <Text style={{ fontSize: 24, marginBottom: 20 }}>Home Screen</Text>
      <Button title="Go to Details" onPress={() => navigation.navigate('Details')} />
    </View>
  );
}

function DetailsScreen({ navigation }) {
  return (
    <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
      <Text style={{ fontSize: 24, marginBottom: 20 }}>Details Screen</Text>
      <Button title="Go Back" onPress={() => navigation.goBack()} />
    </View>
  );
}

export default function App() {
  return (
    <NavigationContainer>
      <Stack.Navigator>
        <Stack.Screen name="Home" component={HomeScreen} />
        <Stack.Screen name="Details" component={DetailsScreen} />
      </Stack.Navigator>
    </NavigationContainer>
  );
}

This app uses React Navigation's native stack navigator to create two screens: Home and Details.

On the Home screen, a button labeled Go to Details calls navigation.navigate('Details') to move to the Details screen.

On the Details screen, a button labeled Go Back calls navigation.goBack() to return to the previous screen.

The Stack.Navigator defines the two screens with their names and components.

This setup creates a simple stack navigation flow, like pages in a book, where you can move forward and back.

Final Result

Completed Screen

Screen 1:
+---------------------+
|    Home Screen      |
|                     |
|  [Go to Details]    |
+---------------------+

Screen 2:
+---------------------+
|   Details Screen    |
|                     |
|  [Go Back]          |
+---------------------+

Tap 'Go to Details' button on Home screen navigates to Details screen

Tap 'Go Back' button on Details screen returns to Home screen

Stretch Goal

Add a header title for each screen that matches the screen name

💡 Hint

Use the 'options' prop on Stack.Screen to set 'title' property

Practice

1. What is the main purpose of a Stack Navigator in React Native?

easy

A. To fetch data from an API

B. To style components with CSS

C. To manage screen navigation like a stack of pages

D. To handle user input events

Solution

1. Step 1: Understand navigation concepts

   Stack Navigator organizes screens so you can move forward and back like a stack of pages.

2. Step 2: Identify the correct purpose

   It is not for styling, fetching data, or handling input but for navigation.

3. Final Answer:

   To manage screen navigation like a stack of pages -> Option C

4. Quick Check:

   Stack Navigator = navigation management [OK]

Hint: Stack Navigator stacks screens for forward/back navigation [OK]

Common Mistakes:

• Confusing navigation with styling
• Thinking it handles data fetching
• Assuming it manages user input

2. Which of the following is the correct way to wrap your app with a stack navigator?

easy

A.

B.

C.

D.

Solution

1. Step 1: Recognize correct nesting

   The NavigationContainer must wrap the entire navigator, which contains Stack.Navigator and its screens.

2. Step 2: Check each option's structure

   Only <NavigationContainer><Stack.Navigator><Stack.Screen name="Home" component={HomeScreen} /></Stack.Navigator></NavigationContainer> correctly wraps Stack.Navigator inside NavigationContainer and includes Stack.Screen.

3. Final Answer:

   <NavigationContainer><Stack.Navigator><Stack.Screen name="Home" component={HomeScreen} /></Stack.Navigator></NavigationContainer> -> Option A

4. Quick Check:

   NavigationContainer wraps Stack.Navigator [OK]

Hint: NavigationContainer wraps Stack.Navigator, which holds screens [OK]

Common Mistakes:

• Placing Stack.Screen outside Stack.Navigator
• Wrapping Stack.Screen directly in NavigationContainer
• Incorrect nesting order of components

3. Given this code snippet, what screen will be shown first when the app runs?

const Stack = createStackNavigator();

function App() {
  return (
    
      
        
        
      
    
  );
}

medium

A. Profile screen

B. Error: No initial screen defined

C. Home screen

D. Settings screen

Solution

1. Step 1: Identify default initial screen

   By default, the first Stack.Screen listed is the initial screen shown.

2. Step 2: Check the order of screens

   The first screen is named "Profile", so the app shows ProfileScreen first.

3. Final Answer:

   Profile screen -> Option A

4. Quick Check:

   First Stack.Screen = initial screen [OK]

Hint: First Stack.Screen listed is the initial screen [OK]

Common Mistakes:

• Assuming Settings is first because of alphabetical order
• Thinking Home screen appears without definition
• Believing an error occurs without initial screen prop

4. What is wrong with this code snippet?

const Stack = createStackNavigator();

function App() {
  return (
    
      
    
  );
}

medium

A. Stack.Screen name must be lowercase

B. Missing NavigationContainer wrapping the navigator

C. HomeScreen component must be imported from react-native

D. Stack.Navigator cannot have only one screen

Solution

1. Step 1: Check for NavigationContainer

   React Navigation requires NavigationContainer to wrap the navigator for proper navigation context.

2. Step 2: Verify other parts

   Screen names can be uppercase, components can be custom, and one screen is allowed.

3. Final Answer:

   Missing NavigationContainer wrapping the navigator -> Option B

4. Quick Check:

   NavigationContainer is required [OK]

Hint: Always wrap Stack.Navigator inside NavigationContainer [OK]

Common Mistakes:

• Omitting NavigationContainer causes navigation failure
• Thinking screen names must be lowercase
• Assuming only built-in components can be screens

5. You want to navigate from the Home screen to the Details screen using a Stack Navigator. Which code snippet correctly performs this navigation inside a button press handler?

function HomeScreen({ navigation }) {
  return (
     ???}
    />
  );
}

hard

A. navigation.push(Details)

B. navigation.popToTop('Details')

C. navigation.goBack('Details')

D. navigation.navigate('Details')

Solution

1. Step 1: Understand navigation methods

   navigation.navigate('ScreenName') moves to a screen, pushing it on the stack if needed.

2. Step 2: Compare options

   push(Details) has a syntax error (missing quotes around screen name); goBack and popToTop are for going back, not forward.

3. Final Answer:

   navigation.navigate('Details') -> Option D

4. Quick Check:

   Use navigate() to go forward to a screen [OK]

Hint: Use navigation.navigate('ScreenName') to move forward [OK]

Common Mistakes:

• Using goBack to go forward
• Using popToTop incorrectly
• Confusing push and navigate methods