Flutter & Firebase Masterclass - Documentation

Cleartext HTTP traffic not permitted (Firebase Local Emulator + Android Emulator)

When signing in with Firebase Auth using the Local Emulator on Android, the following error appears:

I/flutter (24830): [firebase_auth/unknown] com.google.firebase.FirebaseException: An internal error has occurred. [ Cleartext HTTP traffic to 10.0.2.2 not permitted ], #0      StandardMethodCodec.decodeEnvelope

The solution is found in this highly upvoted question on StackOverflow. And I've verified that option 2 in this answer works as intended.

That is - first create the android/app/src/main/res/xml/network_security_config.xml file with these contents:

<?xml version="1.0" encoding="utf-8"?>
<network-security-config>
    <domain-config cleartextTrafficPermitted="true">
        <domain includeSubdomains="true">10.0.2.2</domain>
    </domain-config>
</network-security-config>

Then, add the android:networkSecurityConfig value to the android/app/src/main/AndroidManifest.xml file:

<?xml version="1.0" encoding="utf-8"?>
<manifest ...>
    <application
        ...
        android:networkSecurityConfig="@xml/network_security_config"
        ...>
        ...
    </application>
</manifest>