Custom tab bars in React Native - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a custom tab bar in React Native?

A custom tab bar is a user-designed navigation bar that replaces the default tab bar to provide unique styles or behaviors in a React Native app.

beginner

Which React Navigation component is commonly customized to create a custom tab bar?

The component's tabBar option allows you to provide a custom tab bar component.

intermediate

How do you receive navigation state and descriptors in a custom tab bar component?

The custom tab bar component receives props like state, descriptors, and navigation to control tab selection and rendering.

beginner

Why might you want to create a custom tab bar instead of using the default one?

To match a unique design, add animations, change layout, or include extra buttons not supported by the default tab bar.

beginner

What React Native component is often used inside a custom tab bar to make tabs touchable?

TouchableOpacity or Pressable components are used to make tab buttons respond to user taps.

Which prop provides the current active tab index in a custom tab bar?

A descriptors.active

B navigation.activeTab

C state.index

D tabBar.activeIndex

The state prop contains the navigation state, and state.index gives the active tab index.

What is the purpose of the descriptors prop in a custom tab bar?

A To store user data

B To describe each tab's options and render functions

C To handle gestures

D To manage app state

Descriptors contain options and render functions for each tab screen.

Which React Native component is best for making a tab button respond to taps?

A TouchableOpacity

B Text

C View

D ScrollView

TouchableOpacity provides a touchable area with feedback for taps.

How do you tell React Navigation to use your custom tab bar?

A Pass it to tabBar prop in Tab.Navigator

B Replace Tab.Screen with CustomTab

C Use a different navigator

D Set customTabBar=true

You pass your custom component to the tabBar prop inside Tab.Navigator.

What is a common reason to create a custom tab bar?

A To increase loading speed

B To reduce app size

C To disable navigation

D To add unique styles or animations

Custom tab bars allow unique styles and animations beyond the default.

Explain how to create and use a custom tab bar in React Native with React Navigation.

Think about how the default tab bar works and how you can replace it.

Describe why and when you might want to customize the tab bar in a mobile app.

Consider user interface and user experience needs.