[gtk/a11y/component: 2/4] a11y: Add bounds change api

[Matthias Clasen <matthiasc src gnome org>]

commit d50ebd947ce33ec026a566bdbce5c7ee01457c98
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Oct 19 11:33:38 2020 -0400

    a11y: Add bounds change api
    
    Add a way for GTK to pass bounds change information
    to the AT context.

 gtk/gtkaccessible.c        | 27 +++++++++++++++++++++++++++
 gtk/gtkaccessibleprivate.h |  2 ++
 gtk/gtkatcontext.c         | 12 ++++++++++++
 gtk/gtkatcontextprivate.h  |  3 +++
 4 files changed, 44 insertions(+)
---
diff --git a/gtk/gtkaccessible.c b/gtk/gtkaccessible.c
index 582cdf08fd..bef2ced14e 100644
--- a/gtk/gtkaccessible.c
+++ b/gtk/gtkaccessible.c
@@ -699,6 +699,33 @@ gtk_accessible_get_platform_state (GtkAccessible              *self,
   return GTK_ACCESSIBLE_GET_IFACE (self)->get_platform_state (self, state);
 }
 
+/*<private>
+ * gtk_accessible_bounds_changed:
+ * @self: a #GtkAccessible
+ *
+ * This function can be used to inform ATs that an
+ * accessibles bounds (ie its screen extents) have
+ * changed.
+ *
+ * Note that the bounds are not included in this API.
+ * AT backends should use widget API to obtain them.
+ */
+void
+gtk_accessible_bounds_changed (GtkAccessible *self)
+{
+  GtkATContext *context;
+
+  if (GTK_IS_WIDGET (self) &&
+      gtk_widget_get_root (GTK_WIDGET (self)) == NULL)
+    return;
+
+  context = gtk_accessible_get_at_context (self);
+  if (context == NULL)
+    return;
+
+  gtk_at_context_bounds_changed (context);
+}
+
 /*<private>
  * gtk_accessible_should_present:
  * @self: a #GtkAccessible
diff --git a/gtk/gtkaccessibleprivate.h b/gtk/gtkaccessibleprivate.h
index b3984e3cbd..966efc3abb 100644
--- a/gtk/gtkaccessibleprivate.h
+++ b/gtk/gtkaccessibleprivate.h
@@ -47,4 +47,6 @@ void            gtk_accessible_platform_changed (GtkAccessible                *s
 gboolean        gtk_accessible_get_platform_state (GtkAccessible              *self,
                                                    GtkAccessiblePlatformState  state);
 
+void            gtk_accessible_bounds_changed   (GtkAccessible *self);
+
 G_END_DECLS
diff --git a/gtk/gtkatcontext.c b/gtk/gtkatcontext.c
index 70608a2cb4..1925f5bf80 100644
--- a/gtk/gtkatcontext.c
+++ b/gtk/gtkatcontext.c
@@ -150,6 +150,11 @@ gtk_at_context_real_platform_change (GtkATContext                *self,
 {
 }
 
+static void
+gtk_at_context_real_bounds_change (GtkATContext *self)
+{
+}
+
 static void
 gtk_at_context_class_init (GtkATContextClass *klass)
 {
@@ -161,6 +166,7 @@ gtk_at_context_class_init (GtkATContextClass *klass)
 
   klass->state_change = gtk_at_context_real_state_change;
   klass->platform_change = gtk_at_context_real_platform_change;
+  klass->bounds_change = gtk_at_context_real_bounds_change;
 
   /**
    * GtkATContext:accessible-role:
@@ -820,3 +826,9 @@ gtk_at_context_platform_changed (GtkATContext                *self,
 {
   GTK_AT_CONTEXT_GET_CLASS (self)->platform_change (self, change);
 }
+
+void
+gtk_at_context_bounds_changed (GtkATContext *self)
+{
+  GTK_AT_CONTEXT_GET_CLASS (self)->bounds_change (self);
+}
diff --git a/gtk/gtkatcontextprivate.h b/gtk/gtkatcontextprivate.h
index 872c91e698..d1495538c1 100644
--- a/gtk/gtkatcontextprivate.h
+++ b/gtk/gtkatcontextprivate.h
@@ -122,6 +122,8 @@ struct _GtkATContextClass
 
   void (* platform_change) (GtkATContext                *self,
                             GtkAccessiblePlatformChange  changed_platform);
+
+  void (* bounds_change) (GtkATContext                *self);
 };
 
 GdkDisplay *            gtk_at_context_get_display              (GtkATContext          *self);
@@ -154,6 +156,7 @@ char *                  gtk_at_context_get_label                (GtkATContext
 
 void                    gtk_at_context_platform_changed         (GtkATContext                *self,
                                                                  GtkAccessiblePlatformChange  change);
+void                    gtk_at_context_bounds_changed           (GtkATContext                *self);
 
 const char *    gtk_accessible_property_get_attribute_name      (GtkAccessibleProperty property);
 const char *    gtk_accessible_relation_get_attribute_name      (GtkAccessibleRelation relation);