a11y: Handle HIDDEN state changes

Hidden elements are not presented in the accessible
tree, so when then HIDDEN state changes, we should
emit child-added or -removed signals.

This commit does not yet handle all cases (HIDDEN
toplevels or hidden stack pages are not handled),
but it should cover the common case.

diff --git a/gtk/a11y/gtkatspicontext.c b/gtk/a11y/gtkatspicontext.c
index be3cb128e672fb619088242812d4f2086ef0feef..18a1d7ff9c55a26819b3bc96038dc41b73f32199 100644 (file)
--- a/gtk/a11y/gtkatspicontext.c
+++ b/gtk/a11y/gtkatspicontext.c
@@ -34,7 +34,6 @@
 #include "gtkatspiutilsprivate.h"
 #include "gtkatspivalueprivate.h"
 #include "gtkatspicomponentprivate.h"
-
 #include "a11y/atspi/atspi-accessible.h"
 #include "a11y/atspi/atspi-action.h"
 #include "a11y/atspi/atspi-editabletext.h"
@@ -848,6 +847,29 @@ gtk_at_spi_context_state_change (GtkATContext                *ctx,
   if (!gtk_widget_get_realized (widget))
     return;
 
+  if (changed_states & GTK_ACCESSIBLE_STATE_CHANGE_HIDDEN)
+    {
+      GtkWidget *parent;
+      gboolean hidden;
+
+      value = gtk_accessible_attribute_set_get_value (states, GTK_ACCESSIBLE_STATE_HIDDEN);
+      hidden = gtk_boolean_accessible_value_get (value);
+
+      parent = gtk_widget_get_parent (widget);
+      if (parent)
+        {
+          if (GTK_IS_STACK (parent))
+            g_warning ("Setting GTK_ACCESSIBLE_STATE_HIDDEN on stack children is not supported");
+          else
+            gtk_at_context_child_changed (gtk_accessible_get_at_context (GTK_ACCESSIBLE (parent)),
+                                          hidden ? GTK_ACCESSIBLE_CHILD_CHANGE_REMOVED
+                                                 : GTK_ACCESSIBLE_CHILD_CHANGE_ADDED,
+                                          GTK_ACCESSIBLE (widget));
+        }
+      else
+        g_warning ("Setting GTK_ACCESSIBLE_STATE_HIDDEN on toplevels is not supported");
+    }
+
   if (changed_states & GTK_ACCESSIBLE_STATE_CHANGE_BUSY)
     {
       value = gtk_accessible_attribute_set_get_value (states, GTK_ACCESSIBLE_STATE_BUSY);