[gtk+] Add GtkStackAccessible

[Timm Bäder <baedert src gnome org>]

commit 0b0d4765a00706be78f2485ab0937bc8cbb04031
Author: Timm Bäder <mail baedert org>
Date:   Sun May 29 13:51:02 2016 +0200

    Add GtkStackAccessible
    
    Show only the currently visible child to a11y.

 gtk/a11y/Makefile.inc                |    3 +
 gtk/a11y/gtkstackaccessible.c        |  109 ++++++++++++++++++++++++++++++++++
 gtk/a11y/gtkstackaccessible.h        |   54 +++++++++++++++++
 gtk/a11y/gtkstackaccessibleprivate.h |   32 ++++++++++
 gtk/gtkstack.c                       |    7 ++
 5 files changed, 205 insertions(+), 0 deletions(-)
---
diff --git a/gtk/a11y/Makefile.inc b/gtk/a11y/Makefile.inc
index e13b14c..21c4014 100644
--- a/gtk/a11y/Makefile.inc
+++ b/gtk/a11y/Makefile.inc
@@ -42,6 +42,8 @@ a11y_h_sources =                              \
        a11y/gtkspinbuttonaccessible.h          \
        a11y/gtkspinneraccessible.h             \
        a11y/gtkstatusbaraccessible.h           \
+       a11y/gtkstackaccessible.h               \
+       a11y/gtkstackaccessibleprivate.h        \
        a11y/gtkswitchaccessible.h              \
        a11y/gtktextcellaccessible.h            \
        a11y/gtktextviewaccessible.h            \
@@ -114,6 +116,7 @@ a11y_c_sources =                            \
        a11y/gtkspinbuttonaccessible.c          \
        a11y/gtkspinneraccessible.c             \
        a11y/gtkstatusbaraccessible.c           \
+       a11y/gtkstackaccessible.c               \
        a11y/gtkswitchaccessible.c              \
        a11y/gtktextcellaccessible.c            \
        a11y/gtktextviewaccessible.c            \
diff --git a/gtk/a11y/gtkstackaccessible.c b/gtk/a11y/gtkstackaccessible.c
new file mode 100644
index 0000000..11c2534
--- /dev/null
+++ b/gtk/a11y/gtkstackaccessible.c
@@ -0,0 +1,109 @@
+/* GTK+ - accessibility implementations
+ * Copyright (C) 2016  Timm Bäder <mail baedert org>
+ *
+ * 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 "config.h"
+
+#include <string.h>
+#include <gtk/gtk.h>
+#include "gtkstackaccessible.h"
+#include "gtkwidgetprivate.h"
+
+
+G_DEFINE_TYPE (GtkStackAccessible, gtk_stack_accessible, GTK_TYPE_CONTAINER_ACCESSIBLE)
+
+static AtkObject*
+gtk_stack_accessible_ref_child (AtkObject *obj,
+                                int        i)
+{
+  GtkWidget *stack = gtk_accessible_get_widget (GTK_ACCESSIBLE (obj));
+  GtkWidget *visible_child;
+
+  if (stack == NULL)
+    return NULL;
+
+  if (i != 0)
+    return NULL;
+
+  visible_child = gtk_stack_get_visible_child (GTK_STACK (stack));
+
+  if (visible_child == NULL)
+    return NULL;
+
+  return g_object_ref (gtk_widget_get_accessible (visible_child));
+}
+
+static int
+gtk_stack_accessible_get_n_children (AtkObject *obj)
+{
+  GtkWidget *stack = gtk_accessible_get_widget (GTK_ACCESSIBLE (obj));
+
+  if (stack == NULL)
+    return 0;
+
+  if (gtk_stack_get_visible_child (GTK_STACK (stack)))
+    return 1;
+
+  return 0;
+}
+
+static void
+gtk_stack_accessible_class_init (GtkStackAccessibleClass *klass)
+{
+  AtkObjectClass *class                        = ATK_OBJECT_CLASS (klass);
+  GtkContainerAccessibleClass *container_class = (GtkContainerAccessibleClass*)klass;
+
+  class->get_n_children = gtk_stack_accessible_get_n_children;
+  class->ref_child      = gtk_stack_accessible_ref_child;
+  /*
+   * As we report the stack as having only the visible child,
+   * we are not interested in add and remove signals
+   */
+  container_class->add_gtk    = NULL;
+  container_class->remove_gtk = NULL;
+}
+
+static void
+gtk_stack_accessible_init (GtkStackAccessible *bar) {}
+
+
+void
+gtk_stack_accessible_update_visible_child (GtkStack  *stack,
+                                           GtkWidget *old_visible_child,
+                                           GtkWidget *new_visible_child)
+{
+  AtkObject *stack_accessible = _gtk_widget_peek_accessible (GTK_WIDGET (stack));
+
+  if (stack_accessible == NULL)
+    return;
+
+  if (old_visible_child)
+    {
+      AtkObject *accessible = gtk_widget_get_accessible (old_visible_child);
+      g_object_notify (G_OBJECT (accessible), "accessible-parent");
+      g_signal_emit_by_name (stack_accessible, "children-changed::remove", 0, accessible, NULL);
+    }
+
+  if (new_visible_child)
+    {
+      AtkObject *accessible = gtk_widget_get_accessible (new_visible_child);
+      g_object_notify (G_OBJECT (accessible), "accessible-parent");
+      g_signal_emit_by_name (stack_accessible, "children-changed::add", 0, accessible, NULL);
+    }
+}
+
+
+
diff --git a/gtk/a11y/gtkstackaccessible.h b/gtk/a11y/gtkstackaccessible.h
new file mode 100644
index 0000000..ebd8ab4
--- /dev/null
+++ b/gtk/a11y/gtkstackaccessible.h
@@ -0,0 +1,54 @@
+/* GTK+ - accessibility implementations
+ * Copyright (C) 2016  Timm Bäder <mail baedert org>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __GTK_STACK_ACCESSIBLE_H__
+#define __GTK_STACK_ACCESSIBLE_H__
+
+#if !defined (__GTK_A11Y_H_INSIDE__) && !defined (GTK_COMPILATION)
+#error "Only <gtk/gtk-a11y.h> can be included directly."
+#endif
+
+#include <gtk/a11y/gtkcontaineraccessible.h>
+
+G_BEGIN_DECLS
+
+#define GTK_TYPE_STACK_ACCESSIBLE            (gtk_stack_accessible_get_type ())
+#define GTK_STACK_ACCESSIBLE(obj)            (G_TYPE_CHECK_INSTANCE_CAST ((obj), GTK_TYPE_STACK_ACCESSIBLE, 
GtkStackAccessible))
+#define GTK_STACK_ACCESSIBLE_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST ((klass), GTK_TYPE_STACK_ACCESSIBLE, 
GtkStackAccessibleClass))
+#define GTK_IS_STACK_ACCESSIBLE(obj)         (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GTK_TYPE_STACK_ACCESSIBLE))
+#define GTK_IS_STACK_ACCESSIBLE_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GTK_TYPE_STACK_ACCESSIBLE))
+#define GTK_STACK_ACCESSIBLE_GET_CLASS(obj)  (G_TYPE_INSTANCE_GET_CLASS ((obj), GTK_TYPE_STACK_ACCESSIBLE, 
GtkStackAccessibleClass))
+
+typedef struct _GtkStackAccessible        GtkStackAccessible;
+typedef struct _GtkStackAccessibleClass   GtkStackAccessibleClass;
+
+struct _GtkStackAccessible
+{
+  GtkContainerAccessible parent;
+};
+
+struct _GtkStackAccessibleClass
+{
+  GtkContainerAccessibleClass parent_class;
+};
+
+GDK_AVAILABLE_IN_3_22
+GType gtk_stack_accessible_get_type (void);
+
+G_END_DECLS
+
+#endif
diff --git a/gtk/a11y/gtkstackaccessibleprivate.h b/gtk/a11y/gtkstackaccessibleprivate.h
new file mode 100644
index 0000000..538c8b1
--- /dev/null
+++ b/gtk/a11y/gtkstackaccessibleprivate.h
@@ -0,0 +1,32 @@
+/* GTK+ - accessibility implementations
+ * Copyright (C) 2016  Timm Bäder <mail baedert org>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __GTK_STACK_ACCESSIBLE_PRIVATE_H__
+#define __GTK_STACK_ACCESSIBLE_PRIVATE_H__
+
+#include <gtk/a11y/gtkcontaineraccessible.h>
+
+G_BEGIN_DECLS
+
+void gtk_stack_accessible_update_visible_child (GtkStack  *stack,
+                                                GtkWidget *old_visible_child,
+                                                GtkWidget *new_visible_child);
+
+
+G_END_DECLS
+
+#endif /* __GTK_STACK_ACCESSIBLE_PRIVATE_H__ */
diff --git a/gtk/gtkstack.c b/gtk/gtkstack.c
index 92bc911..22e19a6 100644
--- a/gtk/gtkstack.c
+++ b/gtk/gtkstack.c
@@ -30,6 +30,8 @@
 #include "gtkprogresstrackerprivate.h"
 #include "gtksettingsprivate.h"
 #include "gtkwidgetprivate.h"
+#include "a11y/gtkstackaccessible.h"
+#include "a11y/gtkstackaccessibleprivate.h"
 #include <math.h>
 #include <string.h>
 
@@ -557,6 +559,7 @@ gtk_stack_class_init (GtkStackClass *klass)
 
   gtk_container_class_install_child_properties (container_class, LAST_CHILD_PROP, stack_child_props);
 
+  gtk_widget_class_set_accessible_type (widget_class, GTK_TYPE_STACK_ACCESSIBLE);
   gtk_widget_class_set_css_name (widget_class, "stack");
 }
 
@@ -1116,6 +1119,10 @@ set_visible_child (GtkStack               *stack,
         }
     }
 
+  gtk_stack_accessible_update_visible_child (stack,
+                                             priv->visible_child ? priv->visible_child->widget : NULL,
+                                             child_info ? child_info->widget : NULL);
+
   priv->visible_child = child_info;
 
   if (child_info)