embedder

The Flutter embedder for Tizen.

Build

Prerequisites

• Linux (x64)
• depot_tools
• LLVM (10 or later)
  • sudo apt install clang-12
• Additional dependencies
  • sudo apt install git python3 python3-pip rpm2cpio cpio
  • sudo apt install binutils-arm-linux-gnueabi binutils-aarch64-linux-gnu binutils-i686-linux-gnu
  • pip3 install requests

Environment setup

1. Create an empty directory called embedder and cd into it.

2. Create a .gclient file by running:

   gclient config --name=src --unmanaged https://github.com/flutter-tizen/embedder

3. Run gclient sync to fetch all the source code and dependencies.

   Note: gclient sync must be run every time the DEPS file (or the generate_sysroot.py script) is updated.

Compile

cd into the generated src directory and run the following commands.

Note: The toolchain path (/usr/lib/llvm-12) can be replaced as you want. For example, you can use ~/tizen-studio/tools/llvm-10 if you have Tizen Studio and the NativeToolchain-Gcc-9.2 package installed.

• For arm

  tools/gn --target-cpu arm --target-toolchain /usr/lib/llvm-12
  ninja -C out/tizen_arm

• For arm64

  tools/gn --target-cpu arm64 --target-toolchain /usr/lib/llvm-12
  ninja -C out/tizen_arm64

• For x86

  tools/gn --target-cpu x86 --target-toolchain /usr/lib/llvm-12
  ninja -C out/tizen_x86

Notes

• To build an app (TPK) with the embedder generated in the above, copy the output artifacts (libflutter_tizen*.so) into the flutter-tizen tool's cached artifacts directory (flutter/bin/cache/artifacts/engine) and run flutter-tizen run or flutter-tizen build tpk.
• To use the target device's libstdc++.so instead of the embedder's built-in libc++ (third_party/libcxx), provide the --system-cxx option to tools/gn. Tizen 5.5's libstdc++.so is not compatible with C++17 so you must use a sysroot for Tizen 6.0 or above.
• Building NUI-related code requires a sysroot for Tizen 6.5 or above and the --api-version 6.5 option.

Repository structure

This repository contains the following files and directories.

• //build
  • config: Contains GN configs for setting up the build environment for the toolchain.
  • secondary: The secondary source tree to find input files for build. See the .gn file for details.
• //flutter
  • fml: A subset of the Flutter engine's fml library.
  • shell/platform/common: Contains C++ client wrapper and other common code used by the embedder implementation. Copied from flutter/engine.
  • shell/platform/embedder: Contains embedder.h which defines a low-level API for interacting with the Flutter engine. Copied from flutter/engine.
  • shell/platform/tizen: The Tizen embedder implementation.
    • channels: Internal plugins based on platform channels.
    • public: The public API of the embedder.
  • third_party/accessibility: A fork of the chromium accessibility library. Copied from flutter/engine.
• //tools
  • check_symbols.py: A script to check whether the build artifacts contain symbols not defined in the allowlist. Used by continuous integration.
  • download_engine.py: A script to download engine artifacts required for linking. Executed as a hook by gclient sync. The downloaded artifacts can be found in //engine.
  • generate_sysroot.py: A script to generate Tizen sysroots for arm/arm64/x86. Executed as a hook by gclient sync. The sysroots are by default generated in //sysroot.
  • gn: A script to automate running gn gen.
• .gn: The top-level .gn file referenced by gn.
• DEPS: The DEPS file used by gclient sync to install dependencies and execute hooks.