view: make move_sub_views() use append_children method

...to share common code with minimize_sub_views()

Also, fix a bug in the move-to-back functions to move the window
hierarchy in the right order.

Helped-by: @Consolatis

include/view-impl-common.h

@@ -7,10 +7,17 @@
  * Please note: only xdg-shell-toplevel-view and xwayland-view view_impl
  * functions should call these functions.
  */
+
+enum z_direction {
+	LAB_TO_FRONT,
+	LAB_TO_BACK,
+};
+
 struct view;
 
 void view_impl_move_to_front(struct view *view);
 void view_impl_move_to_back(struct view *view);
+void view_impl_move_sub_views(struct view *parent, enum z_direction z_direction);
 void view_impl_map(struct view *view);
 
 /*

src/view-impl-common.c

@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /* view-impl-common.c: common code for shell view->impl functions */
+#include <assert.h>
 #include <stdio.h>
 #include <strings.h>
 #include "common/list.h"
@@ -24,6 +25,29 @@ view_impl_move_to_back(struct view *view)
 	wlr_scene_node_lower_to_bottom(&view->scene_tree->node);
 }
 
+void
+view_impl_move_sub_views(struct view *parent, enum z_direction z_direction)
+{
+	assert(parent);
+	if (!parent->impl->append_children) {
+		return;
+	}
+
+	struct wl_array subviews;
+	wl_array_init(&subviews);
+	parent->impl->append_children(parent, &subviews);
+
+	struct view **view;
+	wl_array_for_each(view, &subviews) {
+		if (z_direction == LAB_TO_FRONT) {
+			view_impl_move_to_front(*view);
+		} else if (z_direction == LAB_TO_BACK) {
+			view_impl_move_to_back(*view);
+		}
+	}
+	wl_array_release(&subviews);
+}
+
 void
 view_impl_map(struct view *view)
 {

src/xdg.c

@@ -330,49 +330,6 @@ top_parent_of(struct view *view)
 	return toplevel;
 }
 
-enum z_direction {
-	LAB_TO_FRONT,
-	LAB_TO_BACK,
-};
-
-/*
- * TODO: Combine append_children() and move_sub_views() as much as possible.
- * https://github.com/labwc/labwc/pull/998#discussion_r1284085575
- */
-static void
-move_sub_views(struct view *parent, enum z_direction z_direction)
-{
-	assert(parent);
-
-	if (parent->type != LAB_XDG_SHELL_VIEW) {
-		return;
-	}
-
-	struct wlr_xdg_toplevel *parent_toplevel = xdg_toplevel_from_view(parent);
-	struct view *view, *next;
-	wl_list_for_each_reverse_safe(view, next, &parent->server->views, link)
-	{
-		/* need to stop here, otherwise loops keeps going forever */
-		if (view == parent) {
-			break;
-		}
-		if (view->type != LAB_XDG_SHELL_VIEW) {
-			continue;
-		}
-		if (!view->mapped && !view->minimized) {
-			continue;
-		}
-		if (top_parent_of(view) != parent_toplevel) {
-			continue;
-		}
-		if (z_direction == LAB_TO_FRONT) {
-			view_impl_move_to_front(view);
-		} else if (z_direction == LAB_TO_BACK) {
-			view_impl_move_to_back(view);
-		}
-	}
-}
-
 /* Return the most senior parent (=root) view */
 static struct view *
 xdg_toplevel_view_get_root(struct view *view)
@@ -393,15 +350,15 @@ xdg_toplevel_view_move_to_front(struct view *view)
 {
 	struct view *root = xdg_toplevel_view_get_root(view);
 	view_impl_move_to_front(root);
-	move_sub_views(root, LAB_TO_FRONT);
+	view_impl_move_sub_views(root, LAB_TO_FRONT);
 }
 
 static void
 xdg_toplevel_view_move_to_back(struct view *view)
 {
 	struct view *root = xdg_toplevel_view_get_root(view);
+	view_impl_move_sub_views(root, LAB_TO_BACK);
 	view_impl_move_to_back(root);
-	move_sub_views(root, LAB_TO_BACK);
 }
 
 static void

src/xwayland.c

@@ -522,50 +522,6 @@ xwayland_view_minimize(struct view *view, bool minimized)
 		minimized);
 }
 
-enum z_direction {
-	LAB_TO_FRONT,
-	LAB_TO_BACK,
-};
-
-/*
- * TODO: Combine append_children() and move_sub_views() as much as possible.
- * https://github.com/labwc/labwc/pull/998#discussion_r1284085575
- */
-static void
-move_sub_views(struct view *parent, enum z_direction z_direction)
-{
-	assert(parent);
-
-	if (parent->type != LAB_XWAYLAND_VIEW) {
-		return;
-	}
-
-	struct wlr_xwayland_surface *parent_xwayland_surface =
-		xwayland_surface_from_view(parent);
-	struct view *view, *next;
-	wl_list_for_each_reverse_safe(view, next, &parent->server->views, link)
-	{
-		/* need to stop here, otherwise loops keeps going forever */
-		if (view == parent) {
-			break;
-		}
-		if (view->type != LAB_XWAYLAND_VIEW) {
-			continue;
-		}
-		if (!view->mapped && !view->minimized) {
-			continue;
-		}
-		if (top_parent_of(view) != parent_xwayland_surface) {
-			continue;
-		}
-		if (z_direction == LAB_TO_FRONT) {
-			view_impl_move_to_front(view);
-		} else if (z_direction == LAB_TO_BACK) {
-			view_impl_move_to_back(view);
-		}
-	}
-}
-
 static struct view *
 xwayland_view_get_root(struct view *view)
 {
@@ -578,15 +534,15 @@ xwayland_view_move_to_front(struct view *view)
 {
 	struct view *root = xwayland_view_get_root(view);
 	view_impl_move_to_front(root);
-	move_sub_views(root, LAB_TO_FRONT);
+	view_impl_move_sub_views(root, LAB_TO_FRONT);
 }
 
 static void
 xwayland_view_move_to_back(struct view *view)
 {
 	struct view *root = xwayland_view_get_root(view);
+	view_impl_move_sub_views(root, LAB_TO_BACK);
 	view_impl_move_to_back(root);
-	move_sub_views(root, LAB_TO_BACK);
 }
 
 static void