Flutter Dev Container for Android

This project provides a pre-configured development container for building Flutter applications in Android.

Runs on Windows (WSL2 recommended), MacOS (see note at the end) and Linux (at least in theory, please someone test it).

Important

The container currently builds for the amd64 architecture regardless of the host system due to compatibility issues with Apple Silicon chips. I will eventually investigate native architecture builds later, but for now this will do.

Prerequisites

• Docker
• VSCode, or most VSCode forks, or DevPod and most IDEs (see later tip)
• Ability to read

Getting Started

1. Open in Dev Container: Open this project in VS Code and allow it to open in a Dev Container. This will build the Docker image and start the container.

Note

The first time is gonna take a while, depending on how fast your internet is. This is because the SDKs and tools that need to be downloaded are relatively large (5GB approximately).

2. Connect your Android Device:

   • Enable developer mode and Wireless debugging on your Android device.

   • Click on 'Pair device with pairing code'.

   • Open a new terminal in VS Code.

   • Run the following command, replacing YOUR_DEVICE_IP:PORT with the IP and PORT displayed on your phone in the second step:

     task pair-device -- YOUR_DEVICE_IP:PORT

     Input the pairing code.

   • After pairing, run this other command, with the IP address and PORT displayed in the Wireless debugging page (note that the port is different)

     task connect-device -- YOUR_DEVICE_IP:PORT

3. Verify Connection:

   • Run flutter doctor in the terminal.
   • Confirm that a green checkmark appears next to "Connected device".

Tip

You can also use this devcontainer with other IDEs using DevPod. It's free and open source!

Important Note for Alternative IDEs: Some IDEs might default to the sh shell instead of bash, which is the shell configured in this devcontainer. If you're using an IDE other than VS Code, please ensure your terminal is configured to use bash to avoid potential compatibility issues.

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Warning

Currently only Wireless connection is supported. Android 10 and older devices, an extra step going through USB debugging, which is not yet fully supported.

Included Tools and Features

• Flutter SDK
• Android SDK and Command Line Tools
• OpenJDK 17
• VS Code extensions for Flutter and Dart development
• Starship prompt
• Go Task
• Customizable .bashrc

That's it! You're now ready to start developing Flutter apps for Android in a consistent and isolated environment.

Current issues

1. Macs with Apple Silicon chips are forced to use the amd64 builds.

2. On these devices, compiling the app via flutter run succeeds, and hot reloading is fully functional. However, you may see this file watching error during the first debug session (or after cleaning the project):

   Caught exception: Couldn't poll for events, error = 4
   Error while receiving file changes
   net.rubygrapefruit.platform.NativeException: Couldn't poll for events, error = 4
       at net.rubygrapefruit.platform.internal.jni.AbstractNativeFileEventFunctions$NativeFileWatcher.executeRunLoop0(Native Method)
       at net.rubygrapefruit.platform.internal.jni.AbstractNativeFileEventFunctions$NativeFileWatcher.executeRunLoop(AbstractNativeFileEventFunctions.java:42)
       at net.rubygrapefruit.platform.internal.jni.AbstractFileEventFunctions$AbstractFileWatcher$1.run(AbstractFileEventFunctions.java:154)

   Simple workaround: If you see this error, just stop the debug session and restart it. The error only occurs during the initial build when Gradle is establishing file watchers in the cross-architecture environment. Once the build artifacts and cache are created, subsequent runs won't show this error. The error doesn't affect functionality - hot reload and the application will work properly.