a11y: move AtkText implementation from EvViewAccessible to EvPageAccessible

https://bugzilla.gnome.org/show_bug.cgi?id=724965

origin commit:
https://git.gnome.org/browse/evince/commit/?h=gnome-3-14&id=2a458a9

1 files changed, 684 insertions, 1 deletions

diff --git a/libview/ev-page-accessible.c b/libview/ev-page-accessible.c
index 83bb80d8..fa1f3e02 100644
--- a/libview/ev-page-accessible.c
+++ b/libview/ev-page-accessible.c
@@ -22,7 +22,9 @@
 
 #include <config.h>
 
+#include <glib/gi18n-lib.h>
 #include "ev-page-accessible.h"
+#include "ev-view-private.h"
 
 struct _EvPageAccessiblePrivate {
         EvViewAccessible *view_accessible;
@@ -35,8 +37,10 @@ enum {
 	PROP_PAGE,
 };
 
+static void ev_page_accessible_text_iface_init (AtkTextIface *iface);
 
-G_DEFINE_TYPE (EvPageAccessible, ev_page_accessible, ATK_TYPE_OBJECT)
+G_DEFINE_TYPE_WITH_CODE (EvPageAccessible, ev_page_accessible, ATK_TYPE_OBJECT,
+			 G_IMPLEMENT_INTERFACE (ATK_TYPE_TEXT, ev_page_accessible_text_iface_init))
 
 gint
 ev_page_accessible_get_page (EvPageAccessible *page_accessible)
@@ -140,6 +144,666 @@ ev_page_accessible_class_init (EvPageAccessibleClass *klass)
 
 }
 
+EvView *
+ev_page_accessible_get_view (EvPageAccessible *page_accessible)
+{
+	g_return_val_if_fail (EV_IS_PAGE_ACCESSIBLE (page_accessible), NULL);
+
+	return EV_VIEW (gtk_accessible_get_widget (GTK_ACCESSIBLE (page_accessible->priv->view_accessible)));
+}
+
+/* ATs expect to be able to identify sentence boundaries based on content. Valid,
+ * content-based boundaries may be present at the end of a newline, for instance
+ * at the end of a heading within a document. Thus being able to distinguish hard
+ * returns from soft returns is necessary. However, the text we get from Poppler
+ * for non-tagged PDFs has "\n" inserted at the end of each line resulting in a
+ * broken accessibility implementation w.r.t. sentences.
+ */
+static gboolean
+treat_as_soft_return (EvView       *view,
+		      gint          page,
+		      PangoLogAttr *log_attrs,
+		      gint          offset)
+{
+	EvRectangle *areas = NULL;
+	guint n_areas = 0;
+	gdouble line_spacing, this_line_height, next_word_width;
+	EvRectangle *this_line_start;
+	EvRectangle *this_line_end;
+	EvRectangle *next_line_start;
+	EvRectangle *next_line_end;
+	EvRectangle *next_word_end;
+	gint prev_offset, next_offset;
+
+
+	if (!log_attrs[offset].is_white)
+		return FALSE;
+
+	ev_page_cache_get_text_layout (view->page_cache, page, &areas, &n_areas);
+	if (n_areas <= offset + 1)
+		return FALSE;
+
+	prev_offset = offset - 1;
+	next_offset = offset + 1;
+
+	/* In wrapped text, the character at the start of the next line starts a word.
+	 * Examples where this condition might fail include bullets and images. But it
+	 * also includes things like "(", so also check the next character.
+	 */
+	if (!log_attrs[next_offset].is_word_start &&
+	    (next_offset + 1 >= n_areas || !log_attrs[next_offset + 1].is_word_start))
+		return FALSE;
+
+	/* In wrapped text, the chars on either side of the newline have very similar heights.
+	 * Examples where this condition might fail include a newline at the end of a heading,
+	 * and a newline at the end of a paragraph that is followed by a heading.
+	 */
+	this_line_end = areas + prev_offset;
+	next_line_start = areas + next_offset;;
+
+	this_line_height = this_line_end->y2 - this_line_end->y1;
+	if (ABS (this_line_height - (next_line_start->y2 - next_line_start->y1)) > 0.25)
+		return FALSE;
+
+	/* If there is significant white space between this line and the next, odds are this
+	 * is not a soft return in wrapped text. Lines within a typical paragraph are at most
+	 * double-spaced. If the spacing is more than that, assume a hard return is present.
+	 */
+	line_spacing = next_line_start->y1 - this_line_end->y2;
+	if (line_spacing - this_line_height > 1)
+		return FALSE;
+
+	/* Lines within a typical paragraph have *reasonably* similar x1 coordinates. But
+	 * we cannot count on them being nearly identical. Examples where indentation can
+	 * be present in wrapped text include indenting the first line of the paragraph,
+	 * and hanging indents (e.g. in the works cited within an academic paper). So we'll
+	 * be somewhat tolerant here.
+	 */
+	for ( ; prev_offset > 0 && !log_attrs[prev_offset].is_mandatory_break; prev_offset--);
+	this_line_start = areas + prev_offset;
+	if (ABS (this_line_start->x1 - next_line_start->x1) > 20)
+		return FALSE;
+
+	/* Ditto for x2, but this line might be short due to a wide word on the next line. */
+	for ( ; next_offset < n_areas && !log_attrs[next_offset].is_word_end; next_offset++);
+	next_word_end = areas + next_offset;
+	next_word_width = next_word_end->x2 - next_line_start->x1;
+
+	for ( ; next_offset < n_areas && !log_attrs[next_offset + 1].is_mandatory_break; next_offset++);
+	next_line_end = areas + next_offset;
+	if (next_line_end->x2 - (this_line_end->x2 + next_word_width) > 20)
+		return FALSE;
+
+	return TRUE;
+}
+
+static gchar *
+ev_page_accessible_get_substring (AtkText *text,
+				  gint     start_offset,
+				  gint     end_offset)
+{
+	EvPageAccessible *self = EV_PAGE_ACCESSIBLE (text);
+	EvView *view = ev_page_accessible_get_view (self);
+	gchar *substring, *normalized;
+	const gchar* page_text;
+
+	if (!view->page_cache)
+		return NULL;
+
+	page_text = ev_page_cache_get_text (view->page_cache, self->priv->page);
+	start_offset = MAX (0, start_offset);
+	if (end_offset < 0 || end_offset > g_utf8_strlen (page_text, -1))
+		end_offset = strlen (page_text);
+
+	substring = g_utf8_substring (page_text, start_offset, end_offset);
+	normalized = g_utf8_normalize (substring, -1, G_NORMALIZE_NFKC);
+	g_free (substring);
+
+	return normalized;
+}
+
+static gchar *
+ev_page_accessible_get_text (AtkText *text,
+			     gint     start_pos,
+			     gint     end_pos)
+{
+	return ev_page_accessible_get_substring (text, start_pos, end_pos);
+}
+
+static gunichar
+ev_page_accessible_get_character_at_offset (AtkText *text,
+					    gint     offset)
+{
+	gchar *string;
+	gunichar unichar;
+
+	string = ev_page_accessible_get_substring (text, offset, offset + 1);
+	unichar = g_utf8_get_char (string);
+	g_free(string);
+
+	return unichar;
+}
+
+static void
+ev_page_accessible_get_range_for_boundary (AtkText          *text,
+					   AtkTextBoundary   boundary_type,
+					   gint              offset,
+					   gint             *start_offset,
+					   gint             *end_offset)
+{
+	EvPageAccessible *self = EV_PAGE_ACCESSIBLE (text);
+	EvView *view = ev_page_accessible_get_view (self);
+	gint start = 0;
+	gint end = 0;
+	PangoLogAttr *log_attrs = NULL;
+	gulong n_attrs;
+
+	if (!view->page_cache)
+		return;
+
+	ev_page_cache_get_text_log_attrs (view->page_cache, self->priv->page, &log_attrs, &n_attrs);
+	if (!log_attrs)
+		return;
+
+	switch (boundary_type) {
+	case ATK_TEXT_BOUNDARY_CHAR:
+		start = offset;
+		end = offset + 1;
+		break;
+	case ATK_TEXT_BOUNDARY_WORD_START:
+		for (start = offset; start >= 0 && !log_attrs[start].is_word_start; start--);
+		for (end = offset + 1; end <= n_attrs && !log_attrs[end].is_word_start; end++);
+		break;
+	case ATK_TEXT_BOUNDARY_SENTENCE_START:
+		for (start = offset; start >= 0; start--) {
+			if (log_attrs[start].is_mandatory_break && treat_as_soft_return (view, self->priv->page, log_attrs, start - 1))
+				continue;
+			if (log_attrs[start].is_sentence_start)
+				break;
+		}
+		for (end = offset + 1; end <= n_attrs; end++) {
+			if (log_attrs[end].is_mandatory_break && treat_as_soft_return (view, self->priv->page, log_attrs, end - 1))
+				continue;
+			if (log_attrs[end].is_sentence_start)
+				break;
+		}
+		break;
+	case ATK_TEXT_BOUNDARY_LINE_START:
+		for (start = offset; start >= 0 && !log_attrs[start].is_mandatory_break; start--);
+		for (end = offset + 1; end <= n_attrs && !log_attrs[end].is_mandatory_break; end++);
+		break;
+	default:
+		/* The "END" boundary types are deprecated */
+		break;
+	}
+
+	*start_offset = start;
+	*end_offset = end;
+}
+
+static gchar *
+ev_page_accessible_get_text_at_offset (AtkText        *text,
+                                       gint            offset,
+                                       AtkTextBoundary boundary_type,
+                                       gint           *start_offset,
+                                       gint           *end_offset)
+{
+	gchar *retval;
+
+	ev_page_accessible_get_range_for_boundary (text, boundary_type, offset, start_offset, end_offset);
+	retval = ev_page_accessible_get_substring (text, *start_offset, *end_offset);
+
+	/* If newlines appear inside the text of a sentence (i.e. between the start and
+	 * end offsets returned by ev_page_accessible_get_substring), it interferes with
+	 * the prosody of text-to-speech based-solutions such as a screen reader because
+	 * speech synthesizers tend to pause after the newline char as if it were the end
+	 * of the sentence.
+	 */
+        if (boundary_type == ATK_TEXT_BOUNDARY_SENTENCE_START)
+		g_strdelimit (retval, "\n", ' ');
+
+	return retval;
+}
+
+static gint
+ev_page_accessible_get_caret_offset (AtkText *text)
+{
+	EvPageAccessible *self = EV_PAGE_ACCESSIBLE (text);
+	EvView *view = ev_page_accessible_get_view (self);
+
+	if (self->priv->page == view->cursor_page && view->caret_enabled)
+		return view->cursor_offset;
+
+	return -1;
+}
+
+static gboolean
+ev_page_accessible_set_caret_offset (AtkText *text, gint offset)
+{
+	EvPageAccessible *self = EV_PAGE_ACCESSIBLE (text);
+	EvView *view = ev_page_accessible_get_view (self);
+
+	ev_view_set_caret_cursor_position (view,
+					   self->priv->page,
+					   offset);
+
+	return TRUE;
+}
+
+static gint
+ev_page_accessible_get_character_count (AtkText *text)
+{
+	EvPageAccessible *self = EV_PAGE_ACCESSIBLE (text);
+	EvView *view = ev_page_accessible_get_view (self);
+	gint retval;
+
+	retval = g_utf8_strlen (ev_page_cache_get_text (view->page_cache, self->priv->page), -1);
+
+	return retval;
+}
+
+static gboolean
+get_selection_bounds (EvView          *view,
+		      EvViewSelection *selection,
+		      gint            *start_offset,
+		      gint            *end_offset)
+{
+	cairo_rectangle_int_t rect;
+	gint start, end;
+
+	if (!selection->covered_region || cairo_region_is_empty (selection->covered_region))
+		return FALSE;
+
+	cairo_region_get_rectangle (selection->covered_region, 0, &rect);
+	start = _ev_view_get_caret_cursor_offset_at_doc_point (view,
+							       selection->page,
+							       rect.x / view->scale,
+							       (rect.y + (rect.height / 2)) / view->scale);
+	if (start == -1)
+		return FALSE;
+
+	cairo_region_get_rectangle (selection->covered_region,
+				    cairo_region_num_rectangles (selection->covered_region) - 1,
+				    &rect);
+	end = _ev_view_get_caret_cursor_offset_at_doc_point (view,
+							     selection->page,
+							     (rect.x + rect.width) / view->scale,
+							     (rect.y + (rect.height / 2)) / view->scale);
+	if (end == -1)
+		return FALSE;
+
+	*start_offset = start;
+	*end_offset = end;
+
+	return TRUE;
+}
+
+static gint
+ev_page_accessible_get_n_selections (AtkText *text)
+{
+	EvPageAccessible *self = EV_PAGE_ACCESSIBLE (text);
+	EvView *view = ev_page_accessible_get_view (self);
+	gint n_selections = 0;
+	GList *l;
+
+	if (!EV_IS_SELECTION (view->document) || !view->selection_info.selections)
+		return 0;
+
+	for (l = view->selection_info.selections; l != NULL; l = l->next) {
+		EvViewSelection *selection = (EvViewSelection *)l->data;
+
+		if (selection->page != self->priv->page)
+			continue;
+
+		n_selections = 1;
+		break;
+	}
+
+	return n_selections;
+}
+
+static gchar *
+ev_page_accessible_get_selection (AtkText *text,
+				  gint     selection_num,
+				  gint    *start_pos,
+				  gint    *end_pos)
+{
+	EvPageAccessible *self = EV_PAGE_ACCESSIBLE (text);
+	EvView *view = ev_page_accessible_get_view (self);
+	gchar *selected_text = NULL;
+	gchar *normalized_text = NULL;
+	GList *l;
+
+	*start_pos = -1;
+	*end_pos = -1;
+
+	if (selection_num != 0)
+		return NULL;
+
+	if (!EV_IS_SELECTION (view->document) || !view->selection_info.selections)
+		return NULL;
+
+	for (l = view->selection_info.selections; l != NULL; l = l->next) {
+		EvViewSelection *selection = (EvViewSelection *)l->data;
+		gint start, end;
+
+		if (selection->page != self->priv->page)
+			continue;
+
+		if (get_selection_bounds (view, selection, &start, &end) && start != end) {
+			EvPage *page;
+
+			page = ev_document_get_page (view->document, selection->page);
+
+			ev_document_doc_mutex_lock ();
+			selected_text = ev_selection_get_selected_text (EV_SELECTION (view->document),
+									page,
+									selection->style,
+									&(selection->rect));
+
+			ev_document_doc_mutex_unlock ();
+
+			g_object_unref (page);
+
+			*start_pos = start;
+			*end_pos = end;
+		}
+
+		break;
+	}
+
+	if (selected_text) {
+		normalized_text = g_utf8_normalize (selected_text, -1, G_NORMALIZE_NFKC);
+		g_free (selected_text);
+	}
+
+	return normalized_text;
+}
+
+static AtkAttributeSet *
+add_attribute (AtkAttributeSet  *attr_set,
+               AtkTextAttribute  attr_type,
+               gchar            *attr_value)
+{
+  AtkAttribute *attr = g_new (AtkAttribute, 1);
+
+  attr->name = g_strdup (atk_text_attribute_get_name (attr_type));
+  attr->value = attr_value;
+
+  return g_slist_prepend (attr_set, attr);
+}
+
+static AtkAttributeSet *
+get_run_attributes (PangoAttrList   *attrs,
+		    const gchar     *text,
+		    gint             offset,
+		    gint            *start_offset,
+		    gint            *end_offset)
+{
+	AtkAttributeSet   *atk_attr_set = NULL;
+	PangoAttrString   *pango_string;
+	PangoAttrInt      *pango_int;
+	PangoAttrColor    *pango_color;
+	PangoAttrIterator *iter;
+	gint               i, start, end;
+	gboolean           has_attrs = FALSE;
+	glong              text_length;
+	gchar             *attr_value;
+
+	text_length = g_utf8_strlen (text, -1);
+	if (offset < 0 || offset >= text_length)
+		return NULL;
+
+	/* Check if there are attributes for the offset,
+	 * and set the attributes range if positive */
+	iter = pango_attr_list_get_iterator (attrs);
+	i = g_utf8_offset_to_pointer (text, offset) - text;
+
+	do {
+		pango_attr_iterator_range (iter, &start, &end);
+		if (i >= start && i < end) {
+			*start_offset = g_utf8_pointer_to_offset (text, text + start);
+			if (end == G_MAXINT) /* Last iterator */
+				end = text_length;
+			*end_offset = g_utf8_pointer_to_offset (text, text + end);
+			 has_attrs = TRUE;
+		}
+	} while (!has_attrs && pango_attr_iterator_next (iter));
+
+	if (!has_attrs) {
+		pango_attr_iterator_destroy (iter);
+		return NULL;
+	}
+
+	/* Create the AtkAttributeSet from the Pango attributes */
+	pango_string = (PangoAttrString *) pango_attr_iterator_get (iter, PANGO_ATTR_FAMILY);
+	if (pango_string) {
+		attr_value = g_strdup (pango_string->value);
+		atk_attr_set = add_attribute (atk_attr_set, ATK_TEXT_ATTR_FAMILY_NAME, attr_value);
+	}
+
+	pango_int = (PangoAttrInt *) pango_attr_iterator_get (iter, PANGO_ATTR_SIZE);
+	if (pango_int) {
+		attr_value = g_strdup_printf ("%i", pango_int->value / PANGO_SCALE);
+		atk_attr_set = add_attribute (atk_attr_set, ATK_TEXT_ATTR_SIZE, attr_value);
+	}
+
+	pango_int = (PangoAttrInt *) pango_attr_iterator_get (iter, PANGO_ATTR_UNDERLINE);
+	if (pango_int) {
+		atk_attr_set = add_attribute (atk_attr_set,
+					      ATK_TEXT_ATTR_UNDERLINE,
+					      g_strdup (atk_text_attribute_get_value (ATK_TEXT_ATTR_UNDERLINE,
+										      pango_int->value)));
+	}
+
+	pango_color = (PangoAttrColor *) pango_attr_iterator_get (iter, PANGO_ATTR_FOREGROUND);
+	if (pango_color) {
+		attr_value = g_strdup_printf ("%u,%u,%u",
+					      pango_color->color.red,
+					      pango_color->color.green,
+					      pango_color->color.blue);
+		atk_attr_set = add_attribute (atk_attr_set, ATK_TEXT_ATTR_FG_COLOR, attr_value);
+	}
+
+	pango_attr_iterator_destroy (iter);
+
+	return atk_attr_set;
+}
+
+static AtkAttributeSet*
+ev_page_accessible_get_run_attributes (AtkText *text,
+				       gint     offset,
+				       gint    *start_offset,
+				       gint    *end_offset)
+{
+	EvPageAccessible *self = EV_PAGE_ACCESSIBLE (text);
+	EvView *view = ev_page_accessible_get_view (self);
+	PangoAttrList *attrs;
+	const gchar   *page_text;
+
+	if (offset < 0)
+		return NULL;
+
+	if (!view->page_cache)
+		return NULL;
+
+	page_text = ev_page_cache_get_text (view->page_cache, self->priv->page);
+	if (!page_text)
+		return NULL;
+
+	attrs = ev_page_cache_get_text_attrs (view->page_cache, self->priv->page);
+	if (!attrs)
+		return NULL;
+
+	return get_run_attributes (attrs, page_text, offset, start_offset, end_offset);
+}
+
+static AtkAttributeSet*
+ev_page_accessible_get_default_attributes (AtkText *text)
+{
+	/* No default attributes */
+	return NULL;
+}
+
+static void
+ev_page_accessible_get_character_extents (AtkText      *text,
+					  gint         offset,
+					  gint         *x,
+					  gint         *y,
+					  gint         *width,
+					  gint         *height,
+					  AtkCoordType coords)
+{
+	EvPageAccessible *self = EV_PAGE_ACCESSIBLE (text);
+	EvView *view = ev_page_accessible_get_view (self);
+	GtkWidget *toplevel;
+	EvRectangle *areas = NULL;
+	EvRectangle *doc_rect;
+	guint n_areas = 0;
+	gint x_widget, y_widget;
+	GdkRectangle view_rect;
+
+	if (!view->page_cache)
+		return;
+
+	ev_page_cache_get_text_layout (view->page_cache, self->priv->page, &areas, &n_areas);
+	if (!areas || offset >= n_areas)
+		return;
+
+	doc_rect = areas + offset;
+	_ev_view_transform_doc_rect_to_view_rect (view, self->priv->page, doc_rect, &view_rect);
+	view_rect.x -= view->scroll_x;
+	view_rect.y -= view->scroll_y;
+
+	toplevel = gtk_widget_get_toplevel (GTK_WIDGET (view));
+	gtk_widget_translate_coordinates (GTK_WIDGET (view), toplevel, 0, 0, &x_widget, &y_widget);
+	view_rect.x += x_widget;
+	view_rect.y += y_widget;
+
+	if (coords == ATK_XY_SCREEN) {
+		gint x_window, y_window;
+
+		gdk_window_get_origin (gtk_widget_get_window (toplevel), &x_window, &y_window);
+		view_rect.x += x_window;
+		view_rect.y += y_window;
+	}
+
+	*x = view_rect.x;
+	*y = view_rect.y;
+	*width = view_rect.width;
+	*height = view_rect.height;
+}
+
+static gint
+ev_page_accessible_get_offset_at_point (AtkText      *text,
+					gint         x,
+					gint         y,
+					AtkCoordType coords)
+{
+	EvPageAccessible *self = EV_PAGE_ACCESSIBLE (text);
+	EvView *view = ev_page_accessible_get_view (self);
+	GtkWidget *toplevel;
+	EvRectangle *areas = NULL;
+	EvRectangle *rect = NULL;
+	guint n_areas = 0;
+	guint i;
+	gint x_widget, y_widget;
+	gint offset=-1;
+	GdkPoint view_point;
+	gdouble doc_x, doc_y;
+	GtkBorder border;
+	GdkRectangle page_area;
+
+	if (!view->page_cache)
+		return -1;
+
+	ev_page_cache_get_text_layout (view->page_cache, self->priv->page, &areas, &n_areas);
+	if (!areas)
+		return -1;
+
+	view_point.x = x;
+	view_point.y = y;
+	toplevel = gtk_widget_get_toplevel (GTK_WIDGET (self));
+	gtk_widget_translate_coordinates (GTK_WIDGET (self), toplevel, 0, 0, &x_widget, &y_widget);
+	view_point.x -= x_widget;
+	view_point.y -= y_widget;
+
+	if (coords == ATK_XY_SCREEN) {
+		gint x_window, y_window;
+
+		gdk_window_get_origin (gtk_widget_get_window (toplevel), &x_window, &y_window);
+		view_point.x -= x_window;
+		view_point.y -= y_window;
+	}
+
+	ev_view_get_page_extents (view, self->priv->page, &page_area, &border);
+	_ev_view_transform_view_point_to_doc_point (view, &view_point, &page_area, &doc_x, &doc_y);
+
+	for (i = 0; i < n_areas; i++) {
+		rect = areas + i;
+		if (doc_x >= rect->x1 && doc_x <= rect->x2 &&
+		    doc_y >= rect->y1 && doc_y <= rect->y2)
+			offset = i;
+	}
+
+	return offset;
+}
+
+/* ATK allows for multiple, non-contiguous selections within a single AtkText
+ * object. Unless and until Evince supports this, selection numbers are ignored.
+ */
+static gboolean
+ev_page_accessible_remove_selection (AtkText *text,
+				     gint     selection_num)
+{
+	EvPageAccessible *self = EV_PAGE_ACCESSIBLE (text);
+	EvView *view = ev_page_accessible_get_view (self);
+
+	if (ev_view_get_has_selection (view)) {
+		_ev_view_clear_selection (view);
+		return TRUE;
+	}
+
+	return FALSE;
+}
+
+static gboolean
+ev_page_accessible_set_selection (AtkText *text,
+				  gint	   selection_num,
+				  gint     start_pos,
+				  gint     end_pos)
+{
+	EvPageAccessible *self = EV_PAGE_ACCESSIBLE (text);
+	EvView *view = ev_page_accessible_get_view (self);
+	EvRectangle *areas = NULL;
+	guint n_areas = 0;
+	GdkRectangle start_rect, end_rect;
+	GdkPoint start_point, end_point;
+
+	ev_page_cache_get_text_layout (view->page_cache, self->priv->page, &areas, &n_areas);
+	if (start_pos < 0 || end_pos >= n_areas)
+		return FALSE;
+
+	_ev_view_transform_doc_rect_to_view_rect (view, self->priv->page, areas + start_pos, &start_rect);
+	_ev_view_transform_doc_rect_to_view_rect (view, self->priv->page, areas + end_pos - 1, &end_rect);
+	start_point.x = start_rect.x;
+	start_point.y = start_rect.y;
+	end_point.x = end_rect.x + end_rect.width;
+	end_point.y = end_rect.y + end_rect.height;
+	_ev_view_set_selection (view, &start_point, &end_point);
+
+	return TRUE;
+}
+
+static gboolean
+ev_page_accessible_add_selection (AtkText *text,
+				  gint     start_pos,
+				  gint     end_pos)
+{
+	return ev_page_accessible_set_selection (text, 0, start_pos, end_pos);
+
+}
+
 static void
 ev_page_accessible_init (EvPageAccessible *page)
 {
@@ -148,6 +812,25 @@ ev_page_accessible_init (EvPageAccessible *page)
         page->priv = G_TYPE_INSTANCE_GET_PRIVATE (page, EV_TYPE_PAGE_ACCESSIBLE, EvPageAccessiblePrivate);
 }
 
+static void
+ev_page_accessible_text_iface_init (AtkTextIface *iface)
+{
+	iface->get_text = ev_page_accessible_get_text;
+	iface->get_text_at_offset = ev_page_accessible_get_text_at_offset;
+	iface->get_character_at_offset = ev_page_accessible_get_character_at_offset;
+	iface->get_caret_offset = ev_page_accessible_get_caret_offset;
+	iface->set_caret_offset = ev_page_accessible_set_caret_offset;
+	iface->get_character_count = ev_page_accessible_get_character_count;
+	iface->get_n_selections = ev_page_accessible_get_n_selections;
+	iface->get_selection = ev_page_accessible_get_selection;
+	iface->remove_selection = ev_page_accessible_remove_selection;
+	iface->add_selection = ev_page_accessible_add_selection;
+	iface->get_run_attributes = ev_page_accessible_get_run_attributes;
+	iface->get_default_attributes = ev_page_accessible_get_default_attributes;
+	iface->get_character_extents = ev_page_accessible_get_character_extents;
+	iface->get_offset_at_point = ev_page_accessible_get_offset_at_point;
+}
+
 EvPageAccessible *
 ev_page_accessible_new (EvViewAccessible *view_accessible,
                         gint              page)