Open files session files after entering main loop

This change makes the main window show immediately after launching Geany
so it's immediately visible Geany started. With big files/projects this
gives users better feedback about it's starting than not showing anything
until all the files are ready.

src/libmain.c

@@ -144,6 +144,12 @@ static GOptionEntry entries[] =
 	{ NULL, 0, 0, 0, NULL, NULL, NULL }
 };
 
+static struct
+{
+	gint argc;
+	gchar **argv;
+} args;
+
 
 static void setup_window_position(void)
 {
@@ -1003,10 +1009,35 @@ static void setup_gtk2_styles(void)
 #endif
 
 
+static gboolean open_documents(gpointer user_data)
+{
+	GeanyDocument *doc;
+
+	/* load any command line files or session files */
+	main_status.opening_session_files = TRUE;
+	load_startup_files(args.argc, args.argv);
+	main_status.opening_session_files = FALSE;
+
+	/* open a new file if no other file was opened */
+	document_new_file_if_non_open();
+
+	ui_document_buttons_update();
+	ui_save_buttons_toggle(FALSE);
+
+	doc = document_get_current();
+	sidebar_select_openfiles_item(doc);
+	build_menu_update(doc);
+	sidebar_update_tag_list(doc, FALSE);
+
+	document_grab_focus(doc);
+
+	return FALSE;
+}
+
+
 GEANY_EXPORT_SYMBOL
 gint main_lib(gint argc, gchar **argv)
 {
-	GeanyDocument *doc;
 	gint config_dir_result;
 	const gchar *locale;
 
@@ -1163,21 +1194,9 @@ gint main_lib(gint argc, gchar **argv)
 	 * accelerator shown for the menu items */
 	tools_create_insert_custom_command_menu_items();
 
-	/* load any command line files or session files */
-	main_status.opening_session_files = TRUE;
-	load_startup_files(argc, argv);
-	main_status.opening_session_files = FALSE;
-
-	/* open a new file if no other file was opened */
-	document_new_file_if_non_open();
-
-	ui_document_buttons_update();
-	ui_save_buttons_toggle(FALSE);
-
-	doc = document_get_current();
-	sidebar_select_openfiles_item(doc);
-	build_menu_update(doc);
-	sidebar_update_tag_list(doc, FALSE);
+	args.argc = argc;
+	args.argv = argv;
+	g_idle_add(open_documents, NULL);
 
 #ifdef G_OS_WIN32
 	/* Manually realise the main window to be able to set the position but don't show it.
@@ -1187,7 +1206,6 @@ gint main_lib(gint argc, gchar **argv)
 	setup_window_position();
 
 	/* finally show the window */
-	document_grab_focus(doc);
 	configuration_apply_settings();
 	gtk_widget_show(main_widgets.window);
 	main_status.main_window_realized = TRUE;