Building Flutter projects

With Codemagic, you can build and test Flutter apps for Android, iOS, web, macOS and Linux as well as test widgets. It is also possible to set up a workflow that runs tests only.

Selecting build platforms and versions

You can select the platforms to build for and specify the Flutter version, Xcode version and CocoaPods version to be used for building in App settings > Build.

When you’re building for Android, make sure to also specify the Android build format to determine which build artifacts to generate.

This is also where you can selet the build Mode (Debug, Release or Profile) and specify additional build arguments, e.g. for build versioning or verbose logging.

Building Android app bundles

You can build your app in Android App Bundle (.aab) format for publishing to Google Play. When you upload your app in .aab format, app .apk(s) will be dynamically created and optimized for user’s device configuration when the app is installed from Google Play Store.

In App settings > Build > Build for platforms, select Android and then choose Android app bundle (AAB) as the Android build format.

Prepare the app bundle for uploading to Google Play

In order to upload your Android App Bundle to Google Play, you will need to:

1. Build the app in Release mode.
2. Set up Android code signing in Codemagic to sign the app bundle.
3. Set up publishing to Google Play in Codemagic to upload your app bundle to one of Google Play tracks.
4. Enroll your app into app signing by Google Play to have Google sign the .apk(s) that are generated from the app bundle during installation.

When you enroll an app into app signing by Google Play, Google will manage your app’s signing key for you and use it to sign the .apk for distribution. Note that the app must be signed with the same key throughout its lifecycle, so if the app has already been uploaded to Google Play, make sure to export and upload your original key to Google Play for app signing. It is then recommended to create a new key (“upload key”) for signing your app updates and uploading them to Google Play.

Building for the web

Codemagic can detect your Flutter web project if it contains a web folder. To build for the web, select Web as the build platform in App settings > Build > Build for platforms.

At the end of a successful build, Codemagic generates a .zip file of the contents of $FCI_BUILD_DIR/build and exports this as an artifact. You can either download it or set up publishing to Codemagic Static Pages. You can also use custom scripts to publish to third-party hosting sites.

Building for desktop

You can use Codemagic to build Flutter desktop apps for macOS and Linux. Building Windows apps is not yet supported.

Codemagic can detect your Flutter desktop project if it meets the following conditions:

• The project contains a macos folder for the macOS application
• The project contains a linux folder for the Linux application

To build for the macOS or Linux, select the respective option in App settings > Build > Build for platforms. Make sure to also select a Flutter version that has desktop support available.

At the end of a successful build, Codemagic generates a downloadable .zip file for each desktop platform. The application can be installed on your machine, but since it is built without code signing, you may have to allow installating applications from unidentified developers.

Running tests only

In some cases you may want to run only tests and not build the entire project, e.g. when you’re triggering a build on pull request update. To do so, enable testing, and then in App settings > Build > Build for platforms, select Run tests only. Codemagic will then build the workflow until the testing step and skip building the app.

If tests fail, the status of the build will be “failed” and you’ll receive an email about failing tests. If you have publishing to Slack configured, you’ll receive notifications on build status updates.

Starting builds

Builds can be started manually from Codemagic or automatically in response to events in the repository, see more about automatic build triggering here.

You can start builds manually by clicking Start new build in app settings or build overview. On clicking the button, the Specify build configuration popup is displayed where you can select the branch and the workflow to build. If you also have the codemagic.yaml file available in the repository, you can click Select workflow from codemagic.yaml in the popup to select a YAML workflow to build.

For information about using API calls to trigger builds, look here.

Multiple Flutter projects in one repository

Codemagic supports monorepos and is able to detect multiple Flutter projects in a repository or projects not in the repository root provided that each project has its pubspec.yaml file with flutter dependency.

Initially, the only project path for every application is . — the root of the repository. The repository is scanned for Flutter projects during the first build, and if multiple projects are found, the first build is run for the project with the highest number of platforms available (presence of android, ios etc. directories).

After the first build, you can select the project for building in App settings > Build > Project path dropdown.

If you have changed the location of the project in the repository, renamed its parent directory or added new projects, you may have to rescan project paths by clicking the icon next to the Project path dropdown field. Then select the branch you want to search for projects and click Rescan, which will update the project paths for the chosen branch.