Background

iOS 14 requires NSBonjourServices in an app's Info.plist to prompt the user to give local network permissions to the app. The Flutter engine need this permission set to _dartobservatory._tcp in order to publish the dart VM service (observatory) port (debug/profile only), so the host tooling can discover the port and connect. Optionally, NSLocalNetworkUsageDescription can also be set to customize the permission prompt.

flutter tooling automatically handles this as of flutter/flutter#64988, but add-to-app hosts must add these keys manually. See also flutter/flutter#63893 and https://flutter.dev/docs/development/ios-14#debugging-flutter.

Description

Updated the three add_to_app host apps. The following breakdown uses IOSFullScreen as an example.

1. Renamed app Info.plist to Info-Debug.plist. Made a copy of it called Info-Release.plist and added the second plist to the Xcode project.

2. In Info-Debug.plist only added

<key>NSBonjourServices</key>
<array>
	<string>_dartobservatory._tcp</string>
</array>
<key>NSLocalNetworkUsageDescription</key>
<string>Allow Flutter tools on your computer to connect and debug your application. This prompt will not appear on release builds.</string>

Note: Xcode's plist editor displays NSBonjourServices as "Bonjour services" and NSLocalNetworkUsageDescription as "Privacy - Local Network Usage Description"

3. Changed app target > Build Settings > Info.plist File (INFOPLIST_FILE) to IOSFullScreen/Info-$(CONFIGURATION).plist. This will resolve to the path IOSFullScreen/Info-Debug.plist in Debug and IOSFullScreen/Info-Release.plist

Launching the app in debug now shows the local network permissions pop up:

Additionally, I added the missing IOSFullScreen scheme file so the app can be launched from Xcode.