libview: Use GtkBindings for caret navigation

This allows themes to override the key bindings and API users to move
the caret cursor programmatically using g_signal_emit_by_name.

origin commit:
https://git.gnome.org/browse/evince/commit/?h=gnome-3-10&id=1206ff1

3 files changed, 114 insertions, 47 deletions

diff --git a/libview/ev-view-marshal.list b/libview/ev-view-marshal.list
index fad49248..0ead4025 100644
--- a/libview/ev-view-marshal.list
+++ b/libview/ev-view-marshal.list
@@ -1,2 +1,3 @@
 VOID:ENUM,ENUM
 VOID:INT,INT
+BOOLEAN:ENUM,INT
diff --git a/libview/ev-view-private.h b/libview/ev-view-private.h
index 14221175..696a043f 100644
--- a/libview/ev-view-private.h
+++ b/libview/ev-view-private.h
@@ -178,6 +178,9 @@ struct _EvView {
 	/* Common for button press handling */
 	int pressed_button;
 
+	/* Key bindings propagation */
+	gboolean key_binding_handled;
+
 	/* Information for middle clicking and dragging around. */
 	DragInfo drag_info;
 	
@@ -236,23 +239,26 @@ struct _EvView {
 struct _EvViewClass {
 	GtkContainerClass parent_class;
 
-	void    (*scroll)	          (EvView         *view,
-					   GtkScrollType   scroll,
-					   GtkOrientation  orientation);
-	void    (*handle_link)		  (EvView         *view,
-					   EvLink         *link);
-	void    (*external_link)	  (EvView         *view,
-					   EvLinkAction   *action);
-	void    (*popup_menu)		  (EvView         *view,
-					   GList          *items);
-	void    (*selection_changed)      (EvView         *view);
-	void    (*sync_source)            (EvView         *view,
-					   EvSourceLink   *link);
-	void    (*annot_added)            (EvView         *view,
-					   EvAnnotation   *annot);
-	void    (*annot_removed)          (EvView         *view,
-					   EvAnnotation   *annot);
-	void    (*layers_changed)         (EvView         *view);
+	void     (*scroll)            (EvView         *view,
+	                               GtkScrollType   scroll,
+	                               GtkOrientation  orientation);
+	void     (*handle_link)       (EvView         *view,
+	                               EvLink         *link);
+	void     (*external_link)     (EvView         *view,
+	                               EvLinkAction   *action);
+	void     (*popup_menu)        (EvView         *view,
+	                               GList          *items);
+	void     (*selection_changed) (EvView         *view);
+	void     (*sync_source)       (EvView         *view,
+	                               EvSourceLink   *link);
+	void     (*annot_added)       (EvView         *view,
+	                               EvAnnotation   *annot);
+	void     (*annot_removed)     (EvView         *view,
+	                               EvAnnotation   *annot);
+	void     (*layers_changed)    (EvView         *view);
+	gboolean (*move_cursor)       (EvView         *view,
+	                               GtkMovementStep step,
+	                               gint            count);
 };
 
 void _get_page_size_for_scale_and_rotation (EvDocument *document,
diff --git a/libview/ev-view.c b/libview/ev-view.c
index 84ee1487..4f32136a 100644
--- a/libview/ev-view.c
+++ b/libview/ev-view.c
@@ -59,6 +59,7 @@ enum {
 	SIGNAL_ANNOT_ADDED,
 	SIGNAL_ANNOT_REMOVED,
 	SIGNAL_LAYERS_CHANGED,
+	SIGNAL_MOVE_CURSOR,
 	N_SIGNALS
 };
 
@@ -945,6 +946,9 @@ ev_view_scroll (EvView        *view,
 	gboolean first_page = FALSE;
 	gboolean last_page = FALSE;
 
+	if (view->key_binding_handled)
+		return;
+
 	view->jump_to_find_result = FALSE;
 
 	if ((!horizontal && ev_view_page_fits (view, GTK_ORIENTATION_VERTICAL)) ||
@@ -5187,48 +5191,61 @@ cursor_forward_line (EvView *view)
 }
 
 static gboolean
-caret_key_press_event (EvView      *view,
-		       GdkEventKey *event)
+ev_view_move_cursor (EvView         *view,
+		     GtkMovementStep step,
+		     gint            count)
 {
 	gint prev_offset;
 	gint prev_page;
 
-	/* Disable caret navigation on rotated pages */
-	if (view->rotation != 0)
+	if (!view->caret_enabled || view->rotation != 0)
 		return FALSE;
 
+	view->key_binding_handled = TRUE;
 	view->cursor_blink_time = 0;
 
 	prev_offset = view->cursor_offset;
 	prev_page = view->cursor_page;
 
-	switch (event->keyval) {
-	case GDK_KEY_Left:
-		if (event->state & GDK_CONTROL_MASK)
-			cursor_backward_word_start (view);
-		else
+	switch (step) {
+	case GTK_MOVEMENT_VISUAL_POSITIONS:
+		while (count > 0) {
+			cursor_forward_char (view);
+			count--;
+		}
+		while (count < 0) {
 			cursor_backward_char (view);
+			count++;
+		}
 		break;
-	case GDK_KEY_Right:
-		if (event->state & GDK_CONTROL_MASK)
+	case GTK_MOVEMENT_WORDS:
+		while (count > 0) {
 			cursor_forward_word_end (view);
-		else
-			cursor_forward_char (view);
-		break;
-	case GDK_KEY_Up:
-		cursor_backward_line (view);
-		break;
-	case GDK_KEY_Down:
-		cursor_forward_line (view);
+			count--;
+		}
+		while (count < 0) {
+			cursor_backward_word_start (view);
+			count++;
+		}
 		break;
-	case GDK_KEY_Home:
-		cursor_go_to_line_start (view);
+	case GTK_MOVEMENT_DISPLAY_LINES:
+		while (count > 0) {
+			cursor_forward_line (view);
+			count--;
+		}
+		while (count < 0) {
+			cursor_backward_line (view);
+			count++;
+		}
 		break;
-	case GDK_KEY_End:
-		cursor_go_to_line_end (view);
+	case GTK_MOVEMENT_DISPLAY_LINE_ENDS:
+		if (count > 0)
+			cursor_go_to_line_end (view);
+		else if (count < 0)
+			cursor_go_to_line_start (view);
 		break;
 	default:
-		return FALSE;
+		g_assert_not_reached ();
 	}
 
 	ev_view_pend_cursor_blink (view);
@@ -5237,7 +5254,7 @@ caret_key_press_event (EvView      *view,
 	if (prev_offset != view->cursor_offset || prev_page != view->cursor_page) {
 		GdkRectangle view_rect;
 
-		/* scroll to view the text caret */
+		/* scroll to view the caret cursor */
 		if (!get_caret_cursor_rect_from_offset (view, view->cursor_offset, view->cursor_page, &view_rect))
 			return TRUE;
 
@@ -5253,18 +5270,23 @@ static gboolean
 ev_view_key_press_event (GtkWidget   *widget,
 			 GdkEventKey *event)
 {
-	EvView *view = EV_VIEW (widget);
+	EvView  *view = EV_VIEW (widget);
+	gboolean retval;
 
 	if (!view->document)
 		return FALSE;
 
-	if (view->caret_enabled && caret_key_press_event (view, event))
-		return TRUE;
-
 	if (!gtk_widget_has_focus (widget))
 		return ev_view_forward_key_event_to_focused_child (view, event);
 
-	return gtk_bindings_activate_event (G_OBJECT (widget), event);
+	/* I expected GTK+ do this for me, but it doesn't cancel
+	 * the propagation of bindings handled for the same binding set
+	 */
+	view->key_binding_handled = FALSE;
+	retval = gtk_bindings_activate_event (G_OBJECT (widget), event);
+	view->key_binding_handled = FALSE;
+
+	return retval;
 }
 
 static gint
@@ -5943,6 +5965,25 @@ ev_view_parent_set (GtkWidget *widget,
 }
 
 static void
+add_move_binding_keypad (GtkBindingSet  *binding_set,
+			 guint           keyval,
+			 GdkModifierType modifiers,
+			 GtkMovementStep step,
+			 gint            count)
+{
+	guint keypad_keyval = keyval - GDK_KEY_Left + GDK_KEY_KP_Left;
+
+	gtk_binding_entry_add_signal (binding_set, keyval, modifiers,
+				      "move-cursor", 2,
+				      GTK_TYPE_MOVEMENT_STEP, step,
+				      G_TYPE_INT, count);
+	gtk_binding_entry_add_signal (binding_set, keypad_keyval, modifiers,
+				      "move-cursor", 2,
+				      GTK_TYPE_MOVEMENT_STEP, step,
+				      G_TYPE_INT, count);
+}
+
+static void
 ev_view_class_init (EvViewClass *class)
 {
 	GObjectClass *object_class = G_OBJECT_CLASS (class);
@@ -5987,6 +6028,7 @@ ev_view_class_init (EvViewClass *class)
 	container_class->forall = ev_view_forall;
 
 	class->scroll = ev_view_scroll_internal;
+	class->move_cursor = ev_view_move_cursor;
 
 	/* Scrollable interface */
 	g_object_class_override_property (object_class, PROP_HADJUSTMENT, "hadjustment");
@@ -6067,9 +6109,27 @@ ev_view_class_init (EvViewClass *class)
 		         g_cclosure_marshal_VOID__VOID,
 		         G_TYPE_NONE, 0,
 			 G_TYPE_NONE);
+	signals[SIGNAL_MOVE_CURSOR] = g_signal_new ("move-cursor",
+		         G_TYPE_FROM_CLASS (object_class),
+		         G_SIGNAL_RUN_LAST | G_SIGNAL_ACTION,
+		         G_STRUCT_OFFSET (EvViewClass, move_cursor),
+		         NULL, NULL,
+		         ev_view_marshal_BOOLEAN__ENUM_INT,
+		         G_TYPE_BOOLEAN, 2,
+		         GTK_TYPE_MOVEMENT_STEP,
+			 G_TYPE_INT);
 
 	binding_set = gtk_binding_set_by_class (class);
 
+	add_move_binding_keypad (binding_set, GDK_KEY_Left,  0, GTK_MOVEMENT_VISUAL_POSITIONS, -1);
+	add_move_binding_keypad (binding_set, GDK_KEY_Right, 0, GTK_MOVEMENT_VISUAL_POSITIONS, 1);
+	add_move_binding_keypad (binding_set, GDK_KEY_Left,  GDK_CONTROL_MASK, GTK_MOVEMENT_WORDS, -1);
+	add_move_binding_keypad (binding_set, GDK_KEY_Right, GDK_CONTROL_MASK, GTK_MOVEMENT_WORDS, 1);
+	add_move_binding_keypad (binding_set, GDK_KEY_Up,    0, GTK_MOVEMENT_DISPLAY_LINES, -1);
+	add_move_binding_keypad (binding_set, GDK_KEY_Down,  0, GTK_MOVEMENT_DISPLAY_LINES, 1);
+	add_move_binding_keypad (binding_set, GDK_KEY_Home,  0, GTK_MOVEMENT_DISPLAY_LINE_ENDS, -1);
+	add_move_binding_keypad (binding_set, GDK_KEY_End,   0, GTK_MOVEMENT_DISPLAY_LINE_ENDS, 1);
+
 	add_scroll_binding_keypad (binding_set, GDK_KEY_Left,  0, GTK_SCROLL_STEP_BACKWARD, GTK_ORIENTATION_HORIZONTAL);
 	add_scroll_binding_keypad (binding_set, GDK_KEY_Right, 0, GTK_SCROLL_STEP_FORWARD, GTK_ORIENTATION_HORIZONTAL);
 	add_scroll_binding_keypad (binding_set, GDK_KEY_Left,  GDK_MOD1_MASK, GTK_SCROLL_STEP_DOWN, GTK_ORIENTATION_HORIZONTAL);