social_share_kit_facebook #

Facebook SDK add-on for social_share_kit.

The core package bundles no vendor SDKs, which leaves ShareTarget.facebook intent-only on Android and unsupported on iOS — Facebook's iOS app publishes no sharing URL scheme, so a direct share genuinely needs the SDK. Add this package and Facebook works properly on both platforms, with real success, cancel and error reporting.

Everyone else keeps a zero-setup core package. You only pay for this if you want it.

Install #

dependencies:
  social_share_kit: ^0.2.0
  social_share_kit_facebook: ^0.1.0

void main() {
  SocialShareKitFacebook.register();   // once, before the first share
  runApp(const MyApp());
}

Call sites do not change:

// now routed through the native Share Dialog
final result = await SocialShareKit.shareTo(
  ShareTarget.facebook,
  ShareContent.files(['/path/photo.jpg']),
);

result.status == ShareStatus.cancelled;   // the user backed out — now detectable

capabilities(), supportedTargets() and installedTargets() all start reporting through the SDK for that one target automatically.

What changes #

ShareTarget.facebookStory is not claimed by this add-on. The story composer works through the documented pasteboard/intent handoff and needs no SDK, so core keeps it.

Required setup #

This is the cost the core package avoids. All of it comes from Facebook's own integration requirements, not from this package.

Get an app id and client token from developers.facebook.com: Settings → Basic for the app id, Settings → Advanced → Security → Client token for the token.

Android #

android/app/src/main/res/values/strings.xml:

<resources>
    <string name="facebook_app_id">YOUR_APP_ID</string>
    <string name="facebook_client_token">YOUR_CLIENT_TOKEN</string>
</resources>

Inside <application> in android/app/src/main/AndroidManifest.xml:

<meta-data android:name="com.facebook.sdk.ApplicationId"
           android:value="@string/facebook_app_id" />
<meta-data android:name="com.facebook.sdk.ClientToken"
           android:value="@string/facebook_client_token" />

<activity android:name="com.facebook.FacebookActivity"
          android:configChanges="keyboard|keyboardHidden|screenLayout|screenSize|orientation"
          android:exported="false" />

<provider android:name="com.facebook.FacebookContentProvider"
          android:authorities="com.facebook.app.FacebookContentProviderYOUR_APP_ID"
          android:exported="true" />

The provider authority has your app id appended with no separator — ...FacebookContentProvider1234567890. It cannot be declared by this package because the authority embeds a value only you know. Photos reach the Facebook app through it.

The <queries> entries and the FileProvider for video are handled by this add-on's manifest.

iOS #

ios/Runner/Info.plist:

<key>FacebookAppID</key>
<string>YOUR_APP_ID</string>
<key>FacebookClientToken</key>
<string>YOUR_CLIENT_TOKEN</string>
<key>FacebookDisplayName</key>
<string>Your App Name</string>

<key>CFBundleURLTypes</key>
<array>
  <dict>
    <key>CFBundleURLSchemes</key>
    <array><string>fbYOUR_APP_ID</string></array>
  </dict>
</array>

Add fbapi and fb-messenger-share-api to your existing LSApplicationQueriesSchemes array — the SDK probes them to find the Facebook app.

ios/Runner/AppDelegate.swift:

import FBSDKCoreKit

override func application(
  _ application: UIApplication,
  didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
) -> Bool {
  ApplicationDelegate.shared.application(
    application,
    didFinishLaunchingWithOptions: launchOptions
  )
  GeneratedPluginRegistrant.register(with: self)
  return super.application(application, didFinishLaunchingWithOptions: launchOptions)
}

Behaviour worth knowing #

Text is never pre-filled. Facebook has stripped captions the user did not type since Platform Policy 2.3, and the SDK drops them. This package sends ShareContent.text as a hashtag when it is one (a single #word), and otherwise leaves it to you — capabilities().prefillsText is false, which is the honest answer. Use SocialShareKit.copyToClipboard if you want the user to be able to paste it.

Photos and video cannot be mixed in one share; the dialog has no content type for it. Sending both returns unsupportedContent rather than silently dropping one.

Photos are downsampled to a 2048px longest edge before handing them over. Full-resolution decodes of modern camera images are a common out-of-memory crash, and Facebook re-encodes on upload anyway.

success means the dialog reported completion, which for Facebook is genuinely stronger than the core package's "the composer opened" — SharingDelegate and FacebookCallback fire on the real outcome.

Removing it #

Drop the dependency and the register() call. Facebook reverts to intent sharing on Android and unsupportedPlatform on iOS; nothing else in your code changes. SocialShareKitFacebook.unregister() does the same at runtime.

Licence #

MIT. See LICENSE.