[gtk+] Fix indicator proximity checks

[Matthias Clasen <matthiasc src gnome org>]

commit 4c80ac0733289b43377b47fc846507a689747f43
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Apr 6 21:27:17 2015 -0400

    Fix indicator proximity checks
    
    The coordinate translations here were not working properly
    for window widgets inside the scrolled window, as can be
    seen e.g. for the horizontal scrollbar of the 'Tree View'
    example in gtk3-demo.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=747406

 gtk/gtkscrolledwindow.c |   80 +++++++++++++++++++++++++++++++----------------
 1 files changed, 53 insertions(+), 27 deletions(-)
---
diff --git a/gtk/gtkscrolledwindow.c b/gtk/gtkscrolledwindow.c
index 4016122..b3e66b1 100644
--- a/gtk/gtkscrolledwindow.c
+++ b/gtk/gtkscrolledwindow.c
@@ -977,51 +977,77 @@ indicator_set_over (Indicator *indicator,
   gtk_widget_queue_resize (indicator->scrollbar);
 }
 
+static void
+translate_to_widget (GtkWidget *widget,
+                     GdkEvent  *event,
+                     gint      *x,
+                     gint      *y)
+{
+  GtkWidget *event_widget;
+  GdkWindow *event_widget_window;
+  GdkWindow *window;
+  gdouble event_x, event_y;
+  gint wx, wy;
+  GtkAllocation allocation;
+
+  event_widget = gtk_get_event_widget (event);
+  event_widget_window = gtk_widget_get_window (event_widget);
+  gdk_event_get_coords (event, &event_x, &event_y);
+  window = event->any.window;
+  while (window && window != event_widget_window)
+    {
+      gdk_window_get_position (window, &wx, &wy);
+      event_x += wx;
+      event_y += wy;
+      window = gdk_window_get_effective_parent (window);
+    }
+
+  if (!gtk_widget_get_has_window (event_widget))
+    {
+      gtk_widget_get_allocation (event_widget, &allocation);
+      event_x -= allocation.x;
+      event_y -= allocation.y;
+    }
+
+  gtk_widget_translate_coordinates (event_widget, widget,
+                                    (gint)event_x, (gint)event_y,
+                                    x, y);
+}
+
 static gboolean
 event_close_to_indicator (GtkScrolledWindow *sw,
                           Indicator         *indicator,
                           GdkEvent          *event)
 {
-  GtkAllocation alloc, indicator_alloc;
   GtkScrolledWindowPrivate *priv;
-  GtkWidget *event_widget;
-  gint win_x, win_y;
-  gdouble x, y;
+  GtkAllocation indicator_alloc;
+  gint x, y;
   gint distance;
+  gint win_x, win_y;
 
   priv = sw->priv;
-  event_widget = gtk_get_event_widget (event);
-  gdk_event_get_coords (event, &x, &y);
 
-  gtk_widget_get_allocation (GTK_WIDGET (sw), &alloc);
   gtk_widget_get_allocation (indicator->scrollbar, &indicator_alloc);
   gdk_window_get_position (indicator->window, &win_x, &win_y);
-
-  if (event->any.window == indicator->window ||
-      event_widget == indicator->scrollbar)
-    {
-      gint xcoord = x, ycoord = y;
-
-      gtk_widget_translate_coordinates (indicator->scrollbar,
-                                        GTK_WIDGET (sw),
-                                        xcoord, ycoord,
-                                        &xcoord, &ycoord);
-      x = xcoord;
-      y = ycoord;
-    }
+  translate_to_widget (GTK_WIDGET (sw), event, &x, &y);
 
   if (indicator->over)
     distance = INDICATOR_FAR_DISTANCE;
   else
     distance = INDICATOR_CLOSE_DISTANCE;
 
-  if ((indicator == &priv->hindicator &&
-       y >= win_y - distance &&
-       y < win_y + indicator_alloc.height + distance) ||
-      (indicator == &priv->vindicator &&
-       x >= win_x - distance &&
-       x < win_x + indicator_alloc.width + distance))
-    return TRUE;
+  if (indicator == &priv->hindicator)
+    {
+       if (y >= win_y - distance &&
+           y < win_y + indicator_alloc.height + distance)
+         return TRUE;
+    }
+  else if (indicator == &priv->vindicator)
+    {
+      if (x >= win_x - distance &&
+          x < win_x + indicator_alloc.width + distance)
+        return TRUE;
+    }
 
   return FALSE;
 }