Expo MediaLibrary（旧版）

一个提供访问设备媒体库的库。

Android

iOS

tvOS

Included in Expo Go

GitHub

npm

更新日志

Recommended version:

~56.0.11

重要 MediaLibrary API 的旧版本包含在 expo-media-library 库中。它可以与基于类的 expo-media-library API 一起使用，后者可通过根导入暴露。要使用旧版 API，请从 expo-media-library/legacy 导入。

expo-media-library 提供对用户媒体库的访问，允许你的应用访问他们现有的图片和视频，以及保存新的图片和视频。你还可以订阅对用户媒体库所做的任何更新。

警告 Android 仅允许需要广泛访问照片的应用程序完全访问媒体库（这也是此包的用途）。请参阅 Google Play 的照片和视频权限政策详情。

安装

Terminal

- npx expo install expo-media-library

- yarn expo install expo-media-library

- pnpm expo install expo-media-library

- bun expo install expo-media-library

If you are installing this in an existing React Native app, make sure to install expo in your project.

在 app config 中配置

如果你在项目中使用 config plugins（持续原生生成（CNG）），则可以使用 expo-media-library 内置的 config plugin 进行配置。该插件允许你配置各种无法在运行时设置的属性，并且这些属性需要构建新的应用二进制文件后才会生效。如果你的应用不使用 CNG，那么你需要手动配置该库。

Example app.json with config plugin

{
  "expo": {
    "plugins": [
      [
        "expo-media-library",
        {
          "photosPermission": "允许 $(PRODUCT_NAME) 访问你的照片。",
          "savePhotosPermission": "允许 $(PRODUCT_NAME) 保存照片。",
          "isAccessMediaLocationEnabled": true,
          "granularPermissions": ["audio", "photo"]
        }
      ]
    ]
  }
}

Configurable properties

Name	Default	Description
`photosPermission`	`"允许 $(PRODUCT_NAME) 访问你的照片。"`	Only for: iOS 在 Info.plist 中设置 iOS `NSPhotoLibraryUsageDescription` 权限消息。
`savePhotosPermission`	`"允许 $(PRODUCT_NAME) 保存照片。"`	Only for: iOS 在 Info.plist 中设置 iOS `NSPhotoLibraryAddUsageDescription` 权限消息。
`preventAutomaticLimitedAccessAlert`	`false`	Only for: iOS 当用户对照片库的访问受限时，阻止自动显示受限访问提示。适用于只想访问受限照片库、而不希望 iOS 强制显示提示的应用。
`isAccessMediaLocationEnabled`	`false`	Only for: Android 设置是否在 Android 上请求 `ACCESS_MEDIA_LOCATION` 权限。
`granularPermissions`	`["photo", "video", "audio"]`	Only for: Android 设置要包含哪些 `GranularPermission` 值，以决定哪些媒体权限（`READ_MEDIA_IMAGES`、`READ_MEDIA_VIDEO`、`READ_MEDIA_AUDIO`）将被添加到 Android manifest 中。与运行时 API 的行为一致。

Are you using this library in an existing React Native app?

如果你没有使用 Continuous Native Generation（CNG），或者你是手动使用原生 android 和 ios 项目，那么你需要向原生项目添加以下权限和配置：

Android

要访问资产位置（纬度和经度 EXIF 标签），请将 ACCESS_MEDIA_LOCATION 权限添加到项目的 android/app/src/main/AndroidManifest.xml 中：
```
<uses-permission android:name="android.permission.ACCESS_MEDIA_LOCATION" />
```
受限存储从 Android 10 开始可用。为了让 expo-media-library 在受限存储下正常工作，你需要将以下配置添加到 android/app/src/main/AndroidManifest.xml 中：
```
<manifest ... >
  <application android:requestLegacyExternalStorage="true" ...>
</manifest>
```

iOS

将 NSPhotoLibraryUsageDescription 和 NSPhotoLibraryAddUsageDescription 键添加到项目的 ios/[app]/Info.plist 中：

<key>NSPhotoLibraryUsageDescription</key>
<string>授予 $(PRODUCT_NAME) 访问你的照片的权限</string>
<key>NSPhotoLibraryAddUsageDescription</key>
<string>授予 $(PRODUCT_NAME) 保存照片的权限</string>

使用

获取相册并显示资源

import { useState, useEffect } from 'react';
import { Button, Text, ScrollView, StyleSheet, Image, View, Platform } from 'react-native';
import * as MediaLibrary from 'expo-media-library/legacy';

export default function App() {
  const [albums, setAlbums] = useState(null);
  const [permissionResponse, requestPermission] = MediaLibrary.usePermissions();

  async function getAlbums() {
    if (permissionResponse.status !== 'granted') {
      await requestPermission();
    }
    const fetchedAlbums = await MediaLibrary.getAlbumsAsync({
      includeSmartAlbums: true,
    });
    setAlbums(fetchedAlbums);
  }

  return (
    <View style={styles.container}>
      <Button onPress={getAlbums} title="获取相册" />
      <ScrollView>
        {albums && albums.map((album) => <AlbumEntry album={album} />)}
      </ScrollView>
    </View>
  );
}

function AlbumEntry({ album }) {
  const [assets, setAssets] = useState([]);

  useEffect(() => {
    async function getAlbumAssets() {
      const albumAssets = await MediaLibrary.getAssetsAsync({ album });
      setAssets(albumAssets.assets);
    }
    getAlbumAssets();
  }, [album]);

  return (
    <View key={album.id} style={styles.albumContainer}>
      <Text>
        {album.title} - {album.assetCount ?? 'no'} 个资源
      </Text>
      <View style={styles.albumAssetsContainer}>
        {assets && assets.map((asset) => (
          <Image source={{ uri: asset.uri }} width={50} height={50} />
        ))}
      </View>
    </View>
  );
}

%%placeholder-start%%const styles = StyleSheet.create({ ... }); %%placeholder-end%%const styles = StyleSheet.create({
  container: {
    flex: 1,
    gap: 8,
    justifyContent: 'center',
  },
  albumContainer: {
    paddingHorizontal: 20,
    marginBottom: 12,
    gap: 4,
  },
  albumAssetsContainer: {
    flexDirection: 'row',
    flexWrap: 'wrap',
  },
});

已知限制

空相册

由于 Android 的系统限制，无法创建空相册。必须传入一个现有资源以添加到相册中，或者传入一个本地资源的 URI，系统会用它在相册中创建一个新的资源。

在相册之间移动资源

Android 11 引入了权限变更，使得在相册之间移动资源的操作每次都需要用户确认。因此，在创建新资源时，建议不要先创建资源再将其移动到相册，而是将 album 参数传递给 createAssetAsync 方法，这样会自动将资源添加到相册中，而无需用户确认。

图片方向错误

在 Android 上，当使用不带 resolveWithFullInfo: true 的 getAssetsAsync 时，图片方向可能不正确，因为 EXIF 数据（其中包含方向信息）只有在启用该选项时才会读取。

API

import * as MediaLibrary from 'expo-media-library/legacy';

Component

`getAlbumsAsync`

Android

iOS

tvOS

Type: React.Element<AlbumsOptions>

Queries for user-created albums in media gallery.

Constants

`MediaLibrary.MediaType`

Android

iOS

tvOS

Type: MediaTypeObject

Possible media types.

`MediaLibrary.SortBy`

Android

iOS

tvOS

Type: SortByObject

Supported keys that can be used to sort getAssetsAsync results.

Hooks

`usePermissions(options)`

Android

iOS

tvOS

Parameter	Type
options(optional)	`PermissionHookOptions<{ granularPermissions: GranularPermission[], writeOnly: boolean }>`

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

Returns:

[PermissionResponse | null, RequestPermissionMethod<PermissionResponse>, GetPermissionMethod<PermissionResponse>]

Example

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

Methods

`MediaLibrary.addAssetsToAlbumAsync(assets, album, copy)`

Android

iOS

tvOS

Parameter	Type	Description
assets	`AssetRef \| AssetRef[]`	An array of Asset or their IDs.
album	`AlbumRef`	An Album or its ID.
copy(optional)	`boolean`	Android only. Whether to copy assets to the new album instead of move them. Defaults to `true`. Default:`true`

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.

Returns:

Promise<boolean>

Returns promise which fulfils with true if the assets were successfully added to the album.

`MediaLibrary.albumNeedsMigrationAsync(album)`

Android

iOS

tvOS

Parameter	Type	Description
album	`AlbumRef`	An Album or its ID.

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.

Returns:

Promise<boolean>

Returns a promise which fulfils with true if the album should be migrated.

`MediaLibrary.createAlbumAsync(albumName, asset, copyAsset, initialAssetLocalUri)`

Android

iOS

tvOS

Parameter	Type	Description
albumName	`string`	Name of the album to create.
asset(optional)	`AssetRef`	An Asset or its ID. On Android you either need to provide an asset or a localUri.
copyAsset(optional)	`boolean`	Android Only. Whether to copy asset to the new album instead of move it. This parameter is ignored if `asset` was not provided. Defaults to `true`. Default:`true`
initialAssetLocalUri(optional)	`string`	A URI to the local media file, which will be used to create the initial asset inside the album. It must contain an extension. On Android it must be a local path, so it must start with `file:///`. If the `asset` was provided, this parameter will be ignored.

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.

Returns:

Promise<Album>

Newly created Album.

`MediaLibrary.createAssetAsync(localUri, album)`

Android

iOS

tvOS

Parameter	Type	Description
localUri	`string`	A URI to the image or video file. It must contain an extension. On Android it must be a local path, so it must start with `file:///`
album(optional)	`AlbumRef`	An Album or its ID. If provided, the asset will be added to this album upon creation, otherwise it will be added to the default album for the media type. The album has exist.

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.

Returns:

Promise<Asset>

A promise which fulfils with an object representing an Asset.

Example

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

`MediaLibrary.deleteAlbumsAsync(albums, assetRemove)`

Android

iOS

tvOS

Parameter	Type	Description
albums	`AlbumRef \| AlbumRef[]`	An array of `Album`s or their IDs.
assetRemove(optional)	`boolean`	iOS Only. Whether to also delete assets belonging to given albums. Defaults to `false`. Default:`false`

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.

Returns:

Promise<boolean>

Returns a promise which fulfils with true if the albums were successfully deleted from the library.

`MediaLibrary.deleteAssetsAsync(assets)`

Android

iOS

tvOS

Parameter	Type	Description
assets	`AssetRef \| AssetRef[]`	An array of Asset or their IDs.

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.

Returns:

Promise<boolean>

Returns promise which fulfils with true if the assets were successfully deleted.

`MediaLibrary.getAlbumAsync(title)`

Android

iOS

tvOS

Parameter	Type	Description
title	`string`	Name of the album to look for.

Queries for an album with a specific name.

Returns:

Promise<Album>

An object representing an Album, if album with given name exists, otherwise returns null.

`MediaLibrary.getAssetContentUriAsync(asset)`

Android

Parameter	Type	Description
asset	`AssetRef`	An `Asset` or its ID.

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).

Returns:

Promise<string>

A promise which fulfils with the content:// URI string for the asset.

`MediaLibrary.getAssetInfoAsync(asset, options)`

Android

iOS

tvOS

Parameter	Type	Description
asset	`AssetRef`	An Asset or its ID.
options(optional)	`MediaLibraryAssetInfoQueryOptions`	-

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.

Returns:

Promise<AssetInfo>

An AssetInfo object, which is an Asset extended by an additional fields.

`MediaLibrary.getAssetsAsync(assetsOptions)`

Android

iOS

tvOS

Parameter	Type
assetsOptions(optional)	`AssetsOptions`

Fetches a page of assets matching the provided criteria.

Returns:

Promise<PagedInfo<Asset>>

A promise that fulfils with to PagedInfo object with array of Assets.

`MediaLibrary.getMomentsAsync()`

iOS

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

Returns:

Promise<any>

An array of albums whose type is moment.

`MediaLibrary.getPermissionsAsync(writeOnly, granularPermissions)`

Android

iOS

tvOS

Parameter	Type	Description
writeOnly(optional)	`boolean`	Default:`false`
granularPermissions(optional)	`GranularPermission[]`	A list of `GranularPermission` values. This parameter has an effect only on Android 13 and newer. By default, `expo-media-library` will ask for all possible permissions.

Checks user's permissions for accessing media library.

Returns:

Promise<PermissionResponse>

A promise that fulfils with PermissionResponse object.

`MediaLibrary.isAvailableAsync()`

Android

iOS

tvOS

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

Returns:

Promise<boolean>

A promise which fulfils with a boolean, indicating whether the Media Library API is available on the current device.

`MediaLibrary.migrateAlbumIfNeededAsync(album)`

Android

iOS

tvOS

Parameter	Type	Description
album	`AlbumRef`	An Album or its ID.

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.

Returns:

Promise<void>

A promise which fulfils to void.

`MediaLibrary.presentPermissionsPickerAsync(mediaTypes)`

Android 14+

iOS

Parameter	Type	Description
mediaTypes(optional)	`MediaTypeFilter[]`	Limits the type(s) of media that the user will be granting access to. By default, a list that shows both photos and videos is presented.

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.

Returns:

Promise<void>

A promise that either rejects if the method is unavailable, or resolves to void.

Note: This method doesn't inform you if the user changes which assets your app has access to. That information is only exposed by iOS, and to obtain it, you need to subscribe for updates to the user's media library using addListener(). If hasIncrementalChanges is false, the user changed their permissions.

`MediaLibrary.removeAssetsFromAlbumAsync(assets, album)`

Android

iOS

tvOS

Parameter	Type	Description
assets	`AssetRef \| AssetRef[]`	An array of Asset or their IDs.
album	`AlbumRef`	An Album or its ID.

Removes given assets from album.

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

Returns:

Promise<boolean>

Returns promise which fulfils with true if the assets were successfully removed from the album.

`MediaLibrary.removeSubscription(subscription)`

Android

iOS

tvOS

Parameter	Type
subscription	`EventSubscription`

Returns:

void

`MediaLibrary.requestPermissionsAsync(writeOnly, granularPermissions)`

Android

iOS

tvOS

Parameter	Type	Description
writeOnly(optional)	`boolean`	Default:`false`
granularPermissions(optional)	`GranularPermission[]`	A list of `GranularPermission` values. This parameter has an effect only on Android 13 and newer. By default, `expo-media-library` will ask for all possible permissions. When using granular permissions with a custom config plugin configuration, make sure that all the requested permissions are included in plugin.

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

Returns:

Promise<PermissionResponse>

A promise that fulfils with PermissionResponse object.

`MediaLibrary.saveToLibraryAsync(localUri)`

Android

iOS

tvOS

Parameter	Type	Description
localUri	`string`	A URI to the image or video file. It must contain an extension. On Android it must be a local path, so it must start with `file:///`.

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.

Returns:

Promise<void>

`MediaLibrary.setAssetFavoriteAsync(asset, isFavorite)`

iOS

Parameter	Type	Description
asset	`AssetRef`	An Asset or its ID.
isFavorite	`boolean`	Whether the asset should be marked as favorite.

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

Returns:

Promise<boolean>

Returns a promise which fulfils with true if the operation was successful.

Event subscriptions

`MediaLibrary.addListener(listener)`

Android

iOS

tvOS

Parameter	Type	Description
listener	`(event: MediaLibraryAssetsChangeEvent) => void`	A callback that is fired when any assets have been inserted or deleted from the library. On Android it's invoked with an empty object. On iOS, it's invoked with `MediaLibraryAssetsChangeEvent` object. Additionally, only on iOS, the listener is also invoked when the user changes access to individual assets in media library using `presentPermissionsPickerAsync()`.

Subscribes for updates in user's media library.

Returns:

EventSubscription

An Subscription object that you can call remove() on when you would like to unsubscribe the listener.

`MediaLibrary.removeAllListeners()`

Android

iOS

tvOS

Removes all listeners.

Returns:

void

Interfaces

`Subscription`

Android

iOS

tvOS

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

Subscription Methods

`remove()`

Android

iOS

tvOS

Removes an event listener for which the subscription has been created. After calling this function, the listener will no longer receive any events from the emitter.

Returns:

void

Types

`Album`

Android

iOS

tvOS

Property	Type	Description
approximateLocation(optional)	`Location`	Only for: iOS Apply only to albums whose type is `'moment'`. Approximated location of all assets in moment.
assetCount	`number`	Estimated number of assets in album.
endTime	`number`	Only for: iOS Apply only to albums whose type is `'moment'`. Latest creation timestamp of all assets in moment.
id	`string`	Album ID.
locationNames(optional)	`string[]`	Only for: iOS Apply only to albums whose type is `'moment'`. Names of locations grouped in moment.
startTime	`number`	Only for: iOS Apply only to albums whose type is `'moment'`. Earliest creation timestamp of all assets in moment.
title	`string`	Album title.
type(optional)	`AlbumType`	Only for: iOS The type of the assets album.

`AlbumsOptions`

Android

iOS

tvOS

Property	Type	Description
includeSmartAlbums(optional)	`boolean`	-

`AlbumType`

Android

iOS

tvOS

Literal type: string

Acceptable values are: 'album' | 'moment' | 'smartAlbum'

`Asset`

Android

iOS

tvOS

Property	Type	Description
albumId(optional)	`string`	Only for: Android Album ID that the asset belongs to.
creationTime	`number`	File creation timestamp.
duration	`number`	Duration of the video or audio asset in seconds.
filename	`string`	Filename of the asset.
height	`number`	Height of the image or video.
id	`string`	Internal ID that represents an asset.
mediaSubtypes(optional)	`MediaSubtype[]`	Only for: iOS An array of media subtypes.
mediaType	`MediaTypeValue`	Media type.
modificationTime	`number`	Last modification timestamp.
uri	`string`	URI that points to the asset. `ph://` (iOS), `file://` (Android)
width	`number`	Width of the image or video.

`AssetInfo`

Android

iOS

tvOS

Type: Asset extended by:

Property	Type	Description
exif(optional)	`object`	EXIF metadata associated with the image.
isFavorite(optional)	`boolean`	Only for: iOS Whether the asset is marked as favorite.
isNetworkAsset(optional)	`boolean`	Only for: iOS This field is available only if flag `shouldDownloadFromNetwork` is set to `false`. Whether the asset is stored on the network (iCloud on iOS).
localUri(optional)	`string`	Local URI for the asset.
location(optional)	`Location`	GPS location if available.
orientation(optional)	`number`	Only for: iOS Display orientation of the image. Orientation is available only for assets whose `mediaType` is `MediaType.photo`. Value will range from 1 to 8, see EXIF orientation specification for more details.
pairedVideoAsset(optional)	`Asset \| null`	Only for: iOS Contains information about the video paired with the image file. This field is available if the `mediaType` is `"photo"`, and the `mediaSubtypes` includes `"livePhoto"`.

`AssetsOptions`

Android

iOS

tvOS

Property	Type	Description
after(optional)	`AssetRef`	Asset ID of the last item returned on the previous page. To get the ID of the next page, pass `endCursor` as its value.
album(optional)	`AlbumRef`	Album or its ID to get assets from specific album.
createdAfter(optional)	`Date \| number`	`Date` object or Unix timestamp in milliseconds limiting returned assets only to those that were created after this date.
createdBefore(optional)	`Date \| number`	Similarly as `createdAfter`, but limits assets only to those that were created before specified date.
first(optional)	`number`	The maximum number of items on a single page. Default:`20`
mediaSubtypes(optional)	`MediaSubtype[] \| MediaSubtype`	Only for: iOS An array of MediaSubtypes or a single `MediaSubtype`.
mediaType(optional)	`MediaTypeValue[] \| MediaTypeValue`	An array of MediaTypeValues or a single `MediaTypeValue`. Default:`MediaType.photo`
resolveWithFullInfo(optional)	`boolean`	Only for: Android Whether to resolve full info for the assets during the query. This is useful to get the full EXIF data for images. It can fix the orientation of the image. Default:`false`
sortBy(optional)	`SortByValue[] \| SortByValue`	An array of `SortByValue`s or a single `SortByValue` value. By default, all keys are sorted in descending order, however you can also pass a pair `[key, ascending]` where the second item is a `boolean` value that means whether to use ascending order. Note that if the `SortBy.default` key is used, then `ascending` argument will not matter. Earlier items have higher priority when sorting out the results. If empty, this method uses the default sorting that is provided by the platform.

`EXPermissionResponse`

Android

iOS

tvOS

An object obtained by permissions get and request functions.

Property	Type	Description
canAskAgain	`boolean`	Indicates if user can be asked again for specific permission. If not, one should be directed to the Settings app in order to enable/disable the permission.
expires	`PermissionExpiration`	Determines time when the permission expires.
granted	`boolean`	A convenience boolean that indicates if the permission is granted.
status	`PermissionStatus`	Determines the status of the permission.

`GranularPermission`

Android 13+

Literal type: string

Determines the type of media that the app will ask the OS to get access to.

Acceptable values are: 'audio' | 'photo' | 'video'

`Location`

Android

iOS

tvOS

Property	Type	Description
latitude	`number`	-
longitude	`number`	-

`MediaLibraryAssetInfoQueryOptions`

Android

iOS

tvOS

Property	Type	Description
shouldDownloadFromNetwork(optional)	`boolean`	Whether allow the asset to be downloaded from network. Only available in iOS with iCloud assets. Default:`true`

`MediaLibraryAssetsChangeEvent`

Android

iOS

tvOS

Property	Type	Description
deletedAssets(optional)	`Asset[]`	Available only if `hasIncrementalChanges` is `true`. Array of `Asset`s that have been deleted from the library.
hasIncrementalChanges	`boolean`	Whether the media library's changes could be described as "incremental changes". `true` indicates the changes are described by the `insertedAssets`, `deletedAssets` and `updatedAssets` values. `false` indicates that the scope of changes is too large and you should perform a full assets reload (eg. a user has changed access to individual assets in the media library).
insertedAssets(optional)	`Asset[]`	Available only if `hasIncrementalChanges` is `true`. Array of `Asset`s that have been inserted to the library.
updatedAssets(optional)	`Asset[]`	Available only if `hasIncrementalChanges` is `true`. Array of `Asset`s that have been updated or completed downloading from network storage (iCloud on iOS).

`MediaSubtype`

iOS

Literal type: string

Constants identifying specific variations of asset media, such as panorama or screenshot photos, and time-lapse or high-frame-rate video. Maps to PHAssetMediaSubtype.

`MediaTypeFilter`

Android 14+

Literal type: string

Represents the possible types of media that the app will ask the OS to get access to when calling presentPermissionsPickerAsync().

Acceptable values are: 'photo' | 'video'

`MediaTypeObject`

Android

iOS

tvOS

Property	Type	Description
audio	`'audio'`	-
photo	`'photo'`	-
unknown	`'unknown'`	-
video	`'video'`	-

`MediaTypeValue`

Android

iOS

tvOS

Literal type: string

Acceptable values are: 'audio' | 'photo' | 'video' | 'unknown' | 'pairedVideo'

`PagedInfo`

Android

iOS

tvOS

Property	Type	Description
assets	`T[]`	A page of `Asset`s fetched by the query.
endCursor	`string`	A marker that indicates where the next page of results should start. On iOS, it is the ID of the last fetched asset. On Android, it is the index of the last fetched asset in query results. This value should be passed as the `after` option to load the next page.
hasNextPage	`boolean`	Whether there are more assets to fetch.
totalCount	`number`	Estimated total number of assets that match the query.

`PermissionExpiration`

Android

iOS

tvOS

Literal type: union

Permission expiration time. Currently, all permissions are granted permanently.

Acceptable values are: 'never' | number

`PermissionHookOptions`

Android

iOS

tvOS

Literal type: union

Acceptable values are: PermissionHookBehavior | Options

`PermissionResponse`

Android

iOS

tvOS

Type: EXPermissionResponse extended by:

Property	Type	Description
accessPrivileges(optional)	`'all' \| 'limited' \| 'none'`	Indicates if your app has access to the whole or only part of the photo library. Possible values are: `'all'` if the user granted your app access to the whole photo library `'limited'` if the user granted your app access only to selected photos (only available on Android API 14+ and iOS 14.0+) `'none'` if user denied or hasn't yet granted the permission

`SortByKey`

Android

iOS

tvOS

Literal type: string

`SortByObject`

Android

iOS

tvOS

Property	Type	Description
creationTime	`'creationTime'`	-
default	`'default'`	-
duration	`'duration'`	-
height	`'height'`	-
mediaType	`'mediaType'`	-
modificationTime	`'modificationTime'`	-
width	`'width'`	-

`SortByValue`

Android

iOS

tvOS

Literal type: union

Acceptable values are: [SortByKey, boolean] | SortByKey

Enums

`PermissionStatus`

Android

iOS

tvOS

`DENIED`

PermissionStatus.DENIED ＝ "denied"

User has denied the permission.

`GRANTED`

PermissionStatus.GRANTED ＝ "granted"

User has granted the permission.

`UNDETERMINED`

PermissionStatus.UNDETERMINED ＝ "undetermined"

User hasn't granted or denied the permission yet.

权限

Android

以下权限会通过此库的 AndroidManifest.xml 自动添加：

Android permission	Description
`READ_EXTERNAL_STORAGE`	Allows an application to read from external storage.
`WRITE_EXTERNAL_STORAGE`	Allows an application to write to external storage.
`READ_MEDIA_IMAGES`	Allows an application to read image files from external storage.
`READ_MEDIA_VIDEO`	Allows an application to read video files from external storage.
`READ_MEDIA_AUDIO`	Allows an application to read audio files from external storage.
`READ_MEDIA_VISUAL_USER_SELECTED`	Allows an application to read image or video files from external storage that a user has selected via the permission prompt photo picker. Apps can check this permission to verify that a user has decided to use the photo picker, instead of granting access to `READ_MEDIA_IMAGES` or `READ_MEDIA_VIDEO`. It does not prevent apps from accessing the standard photo picker manually. This permission should be requested alongside `READ_MEDIA_IMAGES` and/or `READ_MEDIA_VIDEO`, depending on which type of media is desired.

iOS

此库使用以下用途说明键：

Info.plist key	Description
`NSPhotoLibraryUsageDescription`	A message that tells the user why the app is requesting access to the user’s photo library.
`NSPhotoLibraryAddUsageDescription`	A message that tells the user why the app is requesting add-only access to the user’s photo library.