How to create a fcitx addon in app module.

1. Create a new directory for the addon, under app/src/main/cpp/<addon_name>.

2. Create <addon_name>.conf.in.in

   [Addon]
   Name=<Addon Name>
   Type=SharedLibrary
   Library=lib<addon_name>
   Category=Module
   Version=@PROJECT_VERSION@
   OnDemand=True
   Configurable=True

3. Create CMakeLists.txt

   add_definitions(-DFCITX_GETTEXT_DOMAIN=\"fcitx5-android\")
   
   add_library(<addon_name> MODULE <addon_name>.cpp)
   target_link_libraries(<addon_name> Fcitx5::Core)
   
   configure_file(<addon_name>.conf.in.in <addon_name>.conf.in @ONLY)
   fcitx5_translate_desktop_file(${CMAKE_CURRENT_BINARY_DIR}/<addon_name>.conf.in <addon_name>.conf)
   install(FILES "${CMAKE_CURRENT_BINARY_DIR}/<addon_name>.conf"
           DESTINATION "${FCITX_INSTALL_PKGDATADIR}/addon"
           COMPONENT config)

4. Create <addon_name>.h <addon_name>.cpp respectively.

5. If the addon needs to export functions, <addon_name>_public.h is also needed.

6. For every FCITX_ADDON_DECLARE_FUNCTION in <addon_name>_public.h, there MUST be a FCITX_ADDON_EXPORT_FUNCTION in <addon_name>.h.