Build failure in external_app_launcher: "cannot find symbol: class Registrar"

[MattiaudaNicolasCN]

Hello everyone,

I'm encountering a build failure when running flutter build appbundle. The error message is:

../.pub-cache/hosted/pub.dev/external_app_launcher-4.0.1/android/src/main/java/com/example/launchexternalapp/LaunchexternalappPlugin.java:9: error: cannot find symbol
import io.flutter.plugin.common.PluginRegistry.Registrar;
^
symbol: class Registrar
location: interface PluginRegistry
../.pub-cache/hosted/pub.dev/external_app_launcher-4.0.1/android/src/main/java/com/example/launchexternalapp/LaunchexternalappPlugin.java:30: error: cannot find symbol
public static void registerWith(Registrar registrar) {
^
symbol: class Registrar
location: class LaunchexternalappPlugin
2 errors

FAILURE: Build failed with an exception.

• What went wrong:
  Execution failed for task ':external_app_launcher:compileReleaseJavaWithJavac'.

Compilation failed; see the compiler error output for details.

The output of my flutter doctor is:

Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel stable, 3.29.0, on macOS 15.3 24D60 darwin-x64, locale en-IT)
[✓] Android toolchain - develop for Android devices (Android SDK version 34.0.0-rc1)
[✓] Xcode - develop for iOS and macOS (Xcode 16.2)
[✓] Chrome - develop for the web
[✓] Android Studio (version 2021.1)
[✓] VS Code (version 1.97.0)
[✓] Connected device (4 available)
[✓] Network resources

• No issues found!

I tried to resolve modifying the package locally using FlutterPlugin, but if I do that I get a new error:

FAILURE: Build failed with an exception.

• What went wrong:
  Execution failed for task ':package_info_plus:compileReleaseJavaWithJavac'.

error: invalid source release: 17

• Try:

Run with --stacktrace option to get the stack trace.
Run with --info or --debug option to get more log output.
Run with --scan to get full insights.

• Get more help at https://help.gradle.org

BUILD FAILED in 8s
Running Gradle task 'bundleRelease'... 9.5s
Gradle task bundleRelease failed with exit code 1

What could I do to resolve this issue?

Would appreciate any guidance or updates on this. Thanks in advance! 🙏

[a-aslan-blink]

I faced same error, any update?

[xaldarof]

Hi you can downgrade your flutter version if you upgraded flutter to 3.29

They removed import io.flutter.plugin.common.PluginRegistry.Registrar on Flutter 3.29

[xaldarof]

Try replace dependency to this:

  external_app_launcher:
    git:
      url: https://github.com/xaldarof/external_app_launcher.git
      ref: master

[nick-cuypers]

Maybe this helps:
https://docs.flutter.dev/release/breaking-changes/plugin-api-migration

[geekruchika]

Hi All,
I have fixed this in the latest version
external_app_launcher: ^4.0.2