commit	6f4cf4040e832fc85f0aae1e51c2e8cc51cd5478	[log] [tgz]
author	Alexander Biggs <akbiggs@google.com>	Sat Jul 16 19:54:49 2022 +0000
committer	Alexander Biggs <akbiggs@google.com>	Sat Jul 16 19:54:49 2022 +0000
tree	c9581ea12ad3c00324b1f12b6f4a9db8ae3c5162
parent	3fbab51c0319d1ae1e0032bdd572eddc07f46217 [diff]

tree: c9581ea12ad3c00324b1f12b6f4a9db8ae3c5162

README.md

flutter-embedder.git

The Flutter Embedder for Fuchsia is a new in-progress runtime for Flutter apps on Fuchsia. This runtime is built on top of Flutter's embedder platform.

This repository is a work in progress and should be considered experimental.

Requirements

Install a Bazel version no older than the one defined in the WORKSPACE.bazel file, by following the instructions at https://bazel.build/install. In some Linux distributions, sudo apt-get install bazel should be enough.
Make sure this repository has the required submodules:
```
git submodule update --recursive --init
```

Ensure that there are Fuchsia SSH keys in your host machine. You will need them for running the Fuchsia emulator.

 [[ -f "${HOME}/.ssh/fuchsia_ed25519" ]] || ssh-keygen -P "" -t ed25519 -f "${HOME}/.ssh/fuchsia_ed25519" -C "${USER}@$(hostname -f) Shared SSH Key for Fuchsia"

 [[ -f "${HOME}/.ssh/fuchsia_authorized_keys" ]] || ssh-keygen -y -f "${HOME}/.ssh/fuchsia_ed25519" > "${HOME}/.ssh/fuchsia_authorized_keys"

Build and package the sample

Now the repository is ready to build the sample.

Fetch an emulator image and start an emulator:

tools/ffx product-bundle get workstation.qemu-x64
# If running in a graphical environment:
tools/ffx emu start workstation.qemu-x64
# If running in a terminal environment:
tools/ffx emu start --headless workstation.qemu-x64

(optional) Watch the device log in a separate window:
```
tools/ffx log
```
Run the sample app component:
```
scripts/build_and_run_sample_app.sh
```

TODO(akbiggs): The app occasionally gets stuck on a loading screen instead of rendering. Re-running the app usually fixes it. We need to fix this.

Syncing engine artifacts

Occasionally you will need to update the Flutter Engine artifacts (embedder.h and libengine_flutter.so) that are used by the embedder to run Flutter apps. A script is provided for this workflow.

Prerequisites

You will need to get the Flutter Engine source code. Note that this is not just cloning https://github.com/flutter/engine.
$ENGINE_DIR should be set to the src folder of your Flutter Engine checkout, for example ~/engine/src.
$FUCHSIA_EMBEDDER_DIR should be set to your flutter-embedder.git checkout, for example ~/flutter-embedder.
$DEPOT_TOOLS should be set to your depot_tools location, for example ~/depot_tools.
You will need to git stash or git commit any local changes to the Flutter Engine or the script will fail.

Running the script

You can run the script with a flutter/engine Git commit to sync the Engine artifacts to that revision.

scripts/sync_engine_artifacts_to_revision.sh <ENGINE_COMMIT_SHA>

A common workflow is to sync your Engine commit to the Flutter tool in this repository. To do this:

scripts/sync_engine_artifacts_to_revision.sh $(cat $FUCHSIA_EMBEDDER_DIR/third_party/dart-pkg/internal/flutter/flutter/bin/internal/engine.version)