Expo DocumentPicker

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A library that provides access to the system's UI for selecting documents from the available providers on the user's device.

expo-document-picker provides access to the system's UI for selecting documents from the available providers on the user's device.

Platform Compatibility

Android Device	Android Emulator	iOS Device	iOS Simulator	Web

Installation

Terminal

- npx expo install expo-document-picker

If you are installing this in an existing React Native app, start by installing expo in your project. Then, follow the additional instructions as mentioned by the library's README under "Installation in bare React Native projects" section.

Configuration in app.json/app.config.js

You can configure expo-document-picker using its built-in config plugin if you use config plugins in your project (EAS Build or npx expo run:[android|ios]). The plugin allows you to configure various properties that cannot be set at runtime and require building a new app binary to take effect. If your app does not use EAS Build, then you'll need to manually configure the package.

Example app.json with config plugin

If you want to enable iCloud storage features, set the expo.ios.usesIcloudStorage key to true in the app config file as specified configuration properties.

Running EAS Build locally will use iOS capabilities signing to enable the required capabilities before building.

app.json

{
  "expo": {
    "plugins": [
      [
        "expo-document-picker",
        {
          "iCloudContainerEnvironment": "Production"
        }
      ]
    ]
  }
}

Configurable properties

Name	Default	Description
`iCloudContainerEnvironment`	`undefined`	Only for: iOS Sets the iOS `com.apple.developer.icloud-container-environment` entitlement used for AdHoc iOS builds. Possible values: `Development`, `Production`. Learn more.

Are you using this library in a bare React Native app?

Apps that don't use EAS Build and want iCloud storage features must manually configure the iCloud service with CloudKit support for their bundle identifier.

If you enable the iCloud capability through the Apple Developer Console, then be sure to add the following entitlements in your ios/[app]/[app].entitlements file (where dev.expo.my-app if your bundle identifier):

<key>com.apple.developer.icloud-container-identifiers</key>
<array>
    <string>iCloud.dev.expo.my-app</string>
</array>
<key>com.apple.developer.icloud-services</key>
<array>
    <string>CloudDocuments</string>
</array>
<key>com.apple.developer.ubiquity-container-identifiers</key>
<array>
    <string>iCloud.dev.expo.my-app</string>
</array>
<key>com.apple.developer.ubiquity-kvstore-identifier</key>
<string>$(TeamIdentifierPrefix)dev.expo.my-app</string>

Apple Developer Console also requires an iCloud Container to be created. When registering the new container, you are asked to provide a description and identifier for the container. You may enter any name under the description. Under the identifier, add iCloud.<your_bundle_identifier> (same value used for com.apple.developer.icloud-container-identifiers and com.apple.developer.ubiquity-container-identifiers entitlements).

Using with `expo-file-system`

When using expo-document-picker with expo-file-system, it's not always possible for the file system to read the file immediately after the expo-document-picker picks it.

To allow the expo-file-system to read the file immediately after it is picked, you'll need to ensure that the copyToCacheDirectory option is set to true.

API

import * as DocumentPicker from 'expo-document-picker';

Methods

`DocumentPicker.getDocumentAsync(namedParameters)`

Parameter	Type
namedParameters (optional)	`DocumentPickerOptions`

Display the system UI for choosing a document. By default, the chosen file is copied to the app's internal cache directory.

Notes for Web: The system UI can only be shown after user activation (e.g. a Button press). Therefore, calling getDocumentAsync in componentDidMount, for example, will not work as intended. The cancel event will not be returned in the browser due to platform restrictions and inconsistencies across browsers.

Returns:

Promise<DocumentPickerResult>

On success returns a promise that fulfils with DocumentResult object.

If the user cancelled the document picking, the promise resolves to { type: 'cancel' }.

Types

`DocumentPickerAsset`

Name	Type	Description
file (optional)	`File`	Only for: Web `File` object for the parity with web File API.
lastModified (optional)	`number`	Timestamp of last document modification.
mimeType (optional)	`string`	Document MIME type.
name	`string`	Document original name.
size (optional)	`number`	Document size in bytes.
uri	`string`	An URI to the local document file.

`DocumentPickerCanceledResult`

Type representing canceled pick result.

Name	Type	Description
assets	`null`	Always `null` when the request was canceled.
canceled	`true`	Always `true` when the request was canceled.
output (optional)	`null`	Only for: Web Always `null` when the request was canceled.

`DocumentPickerOptions`

Name	Type	Description
copyToCacheDirectory (optional)	`boolean`	If `true`, the picked file is copied to `FileSystem.CacheDirectory`, which allows other Expo APIs to read the file immediately. This may impact performance for large files, so you should consider setting this to `false` if you expect users to pick particularly large files and your app does not need immediate read access. Default:`true`
multiple (optional)	`boolean`	Allows multiple files to be selected from the system UI. Default:`false`
type (optional)	`string \| string[]`	The MIME type(s) of the documents that are available to be picked. It also supports wildcards like `'image/'` to choose any image. To allow any type of document you can use `'/'`. Default:`'/*'`

`DocumentPickerResult`

Literal Type: multiple types

Type representing successful and canceled document pick result.

Acceptable values are: DocumentPickerSuccessResult | DocumentPickerCanceledResult

`DocumentPickerSuccessResult`

Type representing successful pick result.

Name	Type	Description
assets	`DocumentPickerAsset[]`	An array of picked assets.
canceled	`false`	If asset data have been returned this should always be `false`.
output (optional)	`FileList`	Only for: Web `FileList` object for the parity with web File API.