Expo 媒体库（旧版）

Check or request permissions to access the media library. This uses both requestPermissionsAsync and getPermissionsAsync to interact with the permissions.

const [permissionResponse, requestPermission] = MediaLibrary.usePermissions();

Adds array of assets to the album.

On Android, by default it copies assets from the current album to provided one, however it's also possible to move them by passing false as copyAssets argument. In case they're copied you should keep in mind that getAssetsAsync will return duplicated assets.

Checks if the album should be migrated to a different location. In other words, it checks if the application has the write permission to the album folder. If not, it returns true, otherwise false.

Note: For Android below R, web or iOS, this function always returns false.

Creates an album with given name and initial asset. The asset parameter is required on Android, since it's not possible to create empty album on this platform. On Android, by default it copies given asset from the current album to the new one, however it's also possible to move it by passing false as copyAsset argument. In case it's copied you should keep in mind that getAssetsAsync will return duplicated asset.

On Android, it's not possible to create an empty album. You must provide an existing asset to copy or move into the album or an uri of a local file, which will be used to create an initial asset for the album.

Creates an asset from existing file. The most common use case is to save a picture taken by Camera. This method requires CAMERA_ROLL permission.

const { uri } = await Camera.takePictureAsync();
const asset = await MediaLibrary.createAssetAsync(uri);

Deletes given albums from the library. On Android by default it deletes assets belonging to given albums from the library. On iOS it doesn't delete these assets, however it's possible to do by passing true as deleteAssets.

Deletes assets from the library. On iOS it deletes assets from all albums they belong to, while on Android it keeps all copies of them (album is strictly connected to the asset). Also, there is additional dialog on iOS that requires user to confirm this action.

Queries for an album with a specific name.

Returns the content:// URI for the given legacy asset. Use this when migrating to the new class-based API — pass the returned URI as the ID to new Asset(id).

Provides more information about an asset, including GPS location, local URI and EXIF metadata. For better performance, prefer using individual getters such as asset.getLocation() or asset.getExif() to fetch only the data you need.

Fetches a page of assets matching the provided criteria.

Fetches a list of moments, which is a group of assets taken around the same place and time.

Checks user's permissions for accessing media library.

Returns whether the Media Library API is enabled on the current device.

Moves album content to the special media directories on Android R or above if needed. Those new locations are in line with the Android scoped storage - so your application won't lose write permission to those directories in future.

This method does nothing if:

• app is running on iOS, web or Android below R
• app has write permission to the album folder

The migration is possible when the album contains only compatible files types. For instance, movies and pictures are compatible with each other, but music and pictures are not. If automatic migration isn't possible, the function rejects. In that case, you can use methods from the expo-file-system to migrate all your files manually.

Why do you need to migrate files?

Android R introduced a lot of changes in storage system. Now applications can't save anything to the root directory. The only available locations are from the MediaStore API. Unfortunately, the media library stored albums in folders for which, because of those changes, the application doesn't have permissions anymore. However, it doesn't mean you need to migrate all your albums. If your application doesn't add assets to albums, you don't have to migrate. Everything will work as it used to. You can read more about scoped storage in the Android documentation.

Allows the user to update the assets that your app has access to. The system modal is only displayed if the user originally allowed only limited access to their media library, otherwise this method is a no-op.

Removes given assets from album.

On Android, album will be automatically deleted if there are no more assets inside.

Asks the user to grant permissions for accessing media in user's media library.

Saves the file at given localUri to the user's media library. Unlike createAssetAsync(), This method doesn't return created asset. On iOS 11+, it's possible to use this method without asking for CAMERA_ROLL permission, however then yours Info.plist should have NSPhotoLibraryAddUsageDescription key.

On iOS, this adds or removes the asset from the system "Favorites" smart album.

Subscribes for updates in user's media library.

Removes all listeners.

A subscription object that allows to conveniently remove an event listener from the emitter.