Step 1:

void FileMenu::onOpenTriggered() {  if(fileLauncher_) {    fileLauncher_->launchFiles(NULL, files_);  }  else { // use the default launcher    Fm::FileLauncher launcher;    launcher.launchFiles(NULL, files_);  }}

Step 2:

bool launchFiles(QWidget* parent, FmFileInfoList* file_infos) {    GList* fileList = fm_file_info_list_peek_head_link(file_infos);    return launchFiles(parent, fileList);  }

Step 3:

static inline GList* fm_file_info_list_peek_head_link(FmFileInfoList* list){    return fm_list_peek_head_link((FmList*)list);}

Step 4:

bool FileLauncher::launchFiles(QWidget* parent, GList* file_infos) {  FmAppLaunchContext* context = fm_app_launch_context_new_for_widget(parent);  bool ret = fm_launch_files(G_APP_LAUNCH_CONTEXT(context), file_infos, &funcs, this);  g_object_unref(context);  return ret;}

Step 5:

gboolean fm_launch_files(GAppLaunchContext* ctx, GList* file_infos, FmFileLauncher* launcher, gpointer user_data);