Image picker in React Native - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is an Image Picker in mobile apps?

An Image Picker is a tool or component that lets users select images from their device's gallery or take a new photo using the camera.

beginner

Which React Native library is commonly used for image picking?

The 'react-native-image-picker' library is commonly used to let users pick images or videos from their device or camera.

intermediate

What permission is usually required to access the camera or gallery on mobile devices?

Apps need permission to access the camera or photo gallery. On Android, this is usually CAMERA and READ_EXTERNAL_STORAGE permissions. On iOS, permissions are requested automatically when accessing these features.

intermediate

How do you handle the image data returned by an image picker in React Native?

The image picker returns an object with details like the image URI (path), file name, and type. You use the URI to display the image in your app or upload it to a server.

beginner

Why is it important to handle user cancellation in image picking?

Users may cancel picking an image. Handling cancellation prevents app crashes and improves user experience by allowing the app to continue working smoothly.

Which method lets users pick an image from their device in React Native?

A Using a ScrollView

B Using a TextInput component

C Using an Image Picker library

D Using a Button component only

Image Picker libraries provide the interface to select images from device storage or camera.

What is the key piece of data you use to display a picked image in React Native?

A Image URI

B Image file size

C Image file name

D Image type

The URI is the path to the image file and is used to show the image in the app.

What should your app do if the user cancels image picking?

A Force the user to pick an image

B Show an error message and crash

C Close the app

D Handle cancellation gracefully without crashing

Good apps handle cancellation smoothly to keep the user experience positive.

Which permission is NOT typically needed for image picking?

A Camera access

B Location access

C Read external storage

D Write external storage

Location access is unrelated to picking images from gallery or camera.

What React Native hook is commonly used to store the picked image URI?

A useState

B useEffect

C useContext

D useRef

useState stores the image URI so the UI can update when a new image is picked.

Explain how to implement an image picker in a React Native app.

Think about the steps from setup to showing the image.

Describe why handling user cancellation is important in image picking.

Consider what happens if the user changes their mind.