GtkTextView: Fix scrolling of added children

The behaviour of gtk_text_view_add_child_in_window() used to be
quite broken. It scrolled with the window during scrolling, then
jumped to the absolute position when the widget resized. Furthermore,
in 3.10 we broke the first feature, making it always be fixed.

The "proper" way to handle this is to always follow scrolling. This
is what the only user so far (gedit) wants, and if you want some
kind of overlay you should use GtkOverlay instead.

So, this changes the behaviour to something that is internally consistent
and works. I.e. all added widgets scroll with the textview as needed.

https://bugzilla.gnome.org/show_bug.cgi?id=711826

1 files changed, 32 insertions, 9 deletions

diff --git a/gtk/gtktextview.c b/gtk/gtktextview.c
index a2030c922b..b32a24ae44 100644
--- a/gtk/gtktextview.c
+++ b/gtk/gtktextview.c
@@ -3683,6 +3683,15 @@ gtk_text_view_allocate_children (GtkTextView *text_view)
           allocation.x = child->x;
           allocation.y = child->y;
 
+          if (child->type == GTK_TEXT_WINDOW_TEXT ||
+              child->type == GTK_TEXT_WINDOW_LEFT ||
+              child->type == GTK_TEXT_WINDOW_RIGHT)
+            allocation.y -= text_view->priv->yoffset;
+          if (child->type == GTK_TEXT_WINDOW_TEXT ||
+              child->type == GTK_TEXT_WINDOW_TOP ||
+              child->type == GTK_TEXT_WINDOW_BOTTOM)
+            allocation.x -= text_view->priv->xoffset;
+
           gtk_widget_get_preferred_size (child->widget, &child_req, NULL);
 
           allocation.width = child_req.width;
@@ -8159,10 +8168,28 @@ gtk_text_view_value_changed (GtkAdjustment *adjustment,
       while (tmp_list != NULL)
         {
           GtkTextViewChild *child = tmp_list->data;
-          
+          gint child_dx = 0, child_dy = 0;
+
           if (child->anchor)
-            adjust_allocation (child->widget, dx, dy);
-          
+            {
+              child_dx = dx;
+              child_dy = dy;
+            }
+          else
+            {
+              if (child->type == GTK_TEXT_WINDOW_TEXT ||
+                  child->type == GTK_TEXT_WINDOW_LEFT ||
+                  child->type == GTK_TEXT_WINDOW_RIGHT)
+                child_dy = dy;
+              if (child->type == GTK_TEXT_WINDOW_TEXT ||
+                  child->type == GTK_TEXT_WINDOW_TOP ||
+                  child->type == GTK_TEXT_WINDOW_BOTTOM)
+                child_dx = dx;
+            }
+
+          if (child_dx != 0 || child_dy != 0)
+            adjust_allocation (child->widget, child_dx, child_dy);
+
           tmp_list = g_slist_next (tmp_list);
         }
     }
@@ -10070,15 +10097,11 @@ gtk_text_view_add_child_at_anchor (GtkTextView          *text_view,
  *
  * The window must have nonzero size (see
  * gtk_text_view_set_border_window_size()). Note that the child
- * coordinates are given relative to the #GdkWindow in question, and
- * that these coordinates have no sane relationship to scrolling. When
+ * coordinates are given relative to scrolling. When
  * placing a child in #GTK_TEXT_WINDOW_WIDGET, scrolling is
  * irrelevant, the child floats above all scrollable areas. But when
  * placing a child in one of the scrollable windows (border windows or
- * text window), you'll need to compute the child's correct position
- * in buffer coordinates any time scrolling occurs or buffer changes
- * occur, and then call gtk_text_view_move_child() to update the
- * child's position.
+ * text window) it will move with the scrolling as needed.
  */
 void
 gtk_text_view_add_child_in_window (GtkTextView       *text_view,