libview: Update ATK_STATE_SHOWING when the visible page range changes

https://bugzilla.gnome.org/show_bug.cgi?id=728664

origin commit:
https://git.gnome.org/browse/evince/commit/?h=gnome-3-14&id=110a98a
https://git.gnome.org/browse/evince/commit/?h=gnome-3-14&id=c4e98b3

3 files changed, 37 insertions, 0 deletions

diff --git a/libview/ev-view-accessible.c b/libview/ev-view-accessible.c
index c063e366..bcff9100 100644
--- a/libview/ev-view-accessible.c
+++ b/libview/ev-view-accessible.c
@@ -61,6 +61,8 @@ struct _EvViewAccessiblePrivate {
 	GtkScrollType idle_scroll;
 
 	gint previous_cursor_page;
+	gint start_page;
+	gint end_page;
 
 	GPtrArray *children;
 };
@@ -529,3 +531,31 @@ _transform_doc_rect_to_atk_rect (EvViewAccessible *accessible,
 	atk_rect->x2 = view_rect.x + view_rect.width;
 	atk_rect->y2 = view_rect.y + view_rect.height;
 }
+
+void
+ev_view_accessible_set_page_range (EvViewAccessible *accessible,
+				   gint start,
+				   gint end)
+{
+	gint i;
+	AtkObject *page;
+
+	g_return_if_fail (EV_IS_VIEW_ACCESSIBLE (accessible));
+
+	for (i = accessible->priv->start_page; i <= accessible->priv->end_page; i++) {
+		if (i < start || i > end) {
+			page = g_ptr_array_index (accessible->priv->children, i);
+			atk_object_notify_state_change (page, ATK_STATE_SHOWING, FALSE);
+		}
+	}
+
+	for (i = start; i <= end; i++) {
+		if (i < accessible->priv->start_page || i > accessible->priv->end_page) {
+			page = g_ptr_array_index (accessible->priv->children, i);
+			atk_object_notify_state_change (page, ATK_STATE_SHOWING, TRUE);
+		}
+	}
+
+	accessible->priv->start_page = start;
+	accessible->priv->end_page = end;
+}
diff --git a/libview/ev-view-accessible.h b/libview/ev-view-accessible.h
index 34369682..b756b554 100644
--- a/libview/ev-view-accessible.h
+++ b/libview/ev-view-accessible.h
@@ -54,6 +54,9 @@ void       ev_view_accessible_set_model (EvViewAccessible *accessible,
                                          EvDocumentModel  *model);
 gint       ev_view_accessible_get_n_pages (EvViewAccessible *accessible);
 gint       ev_view_accessible_get_relevant_page (EvViewAccessible *accessible);
+void       ev_view_accessible_set_page_range (EvViewAccessible *accessible,
+					      gint start,
+					      gint end);
 void       _transform_doc_rect_to_atk_rect (EvViewAccessible *accessible,
 					    gint              page,
 					    EvRectangle      *doc_rect,
diff --git a/libview/ev-view.c b/libview/ev-view.c
index 9884280b..a7ae53e0 100644
--- a/libview/ev-view.c
+++ b/libview/ev-view.c
@@ -811,6 +811,10 @@ view_update_range_and_current_page (EvView *view)
 					MAX(view->start_page - PAGE_CACHE_NUMBER, 0),
 					MIN(view->end_page + PAGE_CACHE_NUMBER, ev_document_get_n_pages (view->document) - 1),
 					view->selection_info.selections);
+	if (view->accessible)
+		ev_view_accessible_set_page_range (EV_VIEW_ACCESSIBLE (view->accessible),
+						   view->start_page,
+						   view->end_page);
 
 	if (ev_pixbuf_cache_get_surface (view->pixbuf_cache, view->current_page))
 	    gtk_widget_queue_draw (GTK_WIDGET (view));