popover: Add a popover content class

Instead of bending GtkGizmo to the breaking point,
split off a GtkPopoverContent class that just does
what is needed here. Its simpler, and lets us keep
GtkGizmo simpler too.

gtk/gtkpopover.c

@@ -107,7 +107,7 @@
 #include "gtkbinlayout.h"
 #include "gtkenums.h"
 #include "gtktypebuiltins.h"
-#include "gtkgizmoprivate.h"
+#include "gtkpopovercontentprivate.h"
 #include "gtkintl.h"
 #include "gtkprivate.h"
 #include "gtkmain.h"
@@ -880,15 +880,6 @@ node_style_changed_cb (GtkCssNode        *node,
     gtk_widget_queue_draw (widget);
 }
 
-static void
-contents_css_changed (GtkGizmo          *contents,
-                      GtkCssStyleChange *change)
-{
-  if (change == NULL ||
-      gtk_css_style_change_changes_property (change, GTK_CSS_PROPERTY_BOX_SHADOW))
-    gtk_widget_queue_resize (gtk_widget_get_parent (GTK_WIDGET (contents)));
-}
-
 static void
 gtk_popover_init (GtkPopover *popover)
 {
@@ -921,10 +912,8 @@ gtk_popover_init (GtkPopover *popover)
                            G_CALLBACK (node_style_changed_cb), popover, 0);
   g_object_unref (priv->arrow_node);
 
-  priv->contents_widget = gtk_gizmo_new ("contents", NULL, NULL, NULL, NULL,
-                                         (GtkGizmoFocusFunc)gtk_widget_focus_child,
-                                         (GtkGizmoGrabFocusFunc)gtk_widget_grab_focus_child);
-  gtk_gizmo_set_css_changed_func (GTK_GIZMO (priv->contents_widget), contents_css_changed);
+  priv->contents_widget = gtk_popover_content_new ();
+
   gtk_widget_set_layout_manager (priv->contents_widget, gtk_bin_layout_new ());
   gtk_widget_set_parent (priv->contents_widget, GTK_WIDGET (popover));
   gtk_widget_set_overflow (priv->contents_widget, GTK_OVERFLOW_HIDDEN);

gtk/gtkpopovercontent.c

@@ -0,0 +1,88 @@
+/* GTK - The GIMP Toolkit
+ * Copyright (C) 2021 Red Hat, Inc.
+ *
+ * Authors:
+ * - Matthias Clasen <mclasen@redhat.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "gtkpopovercontentprivate.h"
+#include "gtkstylecontextprivate.h"
+
+#include "gtkwidgetprivate.h"
+
+/* A private class used as the child of GtkPopover. The only thing
+ * special here is that we need to queue a resize on the popover when
+ * our shadow changes.
+ */
+
+G_DEFINE_TYPE (GtkPopoverContent, gtk_popover_content, GTK_TYPE_WIDGET);
+
+static void
+gtk_popover_content_css_changed (GtkWidget         *widget,
+                                 GtkCssStyleChange *change)
+{
+  GTK_WIDGET_CLASS (gtk_popover_content_parent_class)->css_changed (widget, change);
+
+  if (change == NULL ||
+      gtk_css_style_change_changes_property (change, GTK_CSS_PROPERTY_BOX_SHADOW))
+    gtk_widget_queue_resize (gtk_widget_get_parent (widget));
+}
+
+static void
+gtk_popover_content_finalize (GObject *object)
+{
+  GtkPopoverContent *self = GTK_POPOVER_CONTENT (object);
+  GtkWidget *widget;
+
+  widget = _gtk_widget_get_first_child (GTK_WIDGET (self));
+  while (widget != NULL)
+    {
+      GtkWidget *next = _gtk_widget_get_next_sibling (widget);
+
+      gtk_widget_unparent (widget);
+
+      widget = next;
+    }
+
+  G_OBJECT_CLASS (gtk_popover_content_parent_class)->finalize (object);
+}
+
+static void
+gtk_popover_content_class_init (GtkPopoverContentClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+  GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);
+
+  object_class->finalize = gtk_popover_content_finalize;
+
+  widget_class->focus = gtk_widget_focus_child;
+  widget_class->grab_focus = gtk_widget_grab_focus_child;
+  widget_class->css_changed = gtk_popover_content_css_changed;
+}
+
+static void
+gtk_popover_content_init (GtkPopoverContent *self)
+{
+}
+
+GtkWidget *
+gtk_popover_content_new (void)
+{
+  return g_object_new (GTK_TYPE_POPOVER_CONTENT,
+                       "css-name", "contents",
+                       "accessible-role", GTK_ACCESSIBLE_ROLE_WIDGET,
+                       NULL);
+}

gtk/gtkpopovercontentprivate.h

@@ -0,0 +1,51 @@
+/* GTK - The GIMP Toolkit
+ * Copyright (C) 2021 Red Hat, Inc.
+ *
+ * Authors:
+ * - Matthias Clasen <mclasen@redhat.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __GTK_POPOVER_CONTENT_H__
+#define __GTK_POPOVER_CONTENT_H__
+
+#include "gtkwidget.h"
+#include "gtkenums.h"
+
+#define GTK_TYPE_POPOVER_CONTENT                 (gtk_popover_content_get_type ())
+#define GTK_POPOVER_CONTENT(obj)                 (G_TYPE_CHECK_INSTANCE_CAST ((obj), GTK_TYPE_POPOVER_CONTENT, GtkPopoverContent))
+#define GTK_POPOVER_CONTENT_CLASS(klass)         (G_TYPE_CHECK_CLASS_CAST ((klass), GTK_TYPE_POPOVER_CONTENT, GtkPopoverContentClass))
+#define GTK_IS_POPOVER_CONTENT(obj)              (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GTK_TYPE_POPOVER_CONTENT))
+#define GTK_IS_POPOVER_CONTENT_CLASS(klass)      (G_TYPE_CHECK_CLASS_TYPE ((klass), GTK_TYPE_POPOVER_CONTENT))
+#define GTK_POPOVER_CONTENT_GET_CLASS(obj)       (G_TYPE_INSTANCE_GET_CLASS ((obj), GTK_TYPE_POPOVER_CONTENT, GtkPopoverContentClass))
+
+typedef struct _GtkPopoverContent             GtkPopoverContent;
+typedef struct _GtkPopoverContentClass        GtkPopoverContentClass;
+
+struct _GtkPopoverContent
+{
+  GtkWidget parent_instance;
+};
+
+struct _GtkPopoverContentClass
+{
+  GtkWidgetClass parent_class;
+};
+
+GType      gtk_popover_content_get_type (void) G_GNUC_CONST;
+
+GtkWidget *gtk_popover_content_new (void);
+
+#endif

gtk/meson.build

@@ -127,6 +127,7 @@ gtk_private_sources = files([
   'gtkplacesview.c',
   'gtkplacesviewrow.c',
   'gtkpointerfocus.c',
+  'gtkpopovercontent.c',
   'gtkprintutils.c',
   'gtkprivate.c',
   'gtkprogresstracker.c',