[gnome-shell] Incremental fixes for scrollview work

[Owen Taylor <otaylor src gnome org>]

commit f6cbb14393ba1f53b5677f2568ec087e79e26f87
Author: Owen W. Taylor <otaylor fishsoup net>
Date:   Wed Mar 10 11:56:04 2010 -0500

    Incremental fixes for scrollview work
    
    - Fix existing typos and spacing problems
    - Get preferred height, not current height, of shadows
    - Let shadows overflow don't clamp them when we have too little space
    - Remove a now-unecessary stray MAX()
    - Fix up scrollview visibility for the pathological case of no child
    - Disconnect from adjustments on remove()
    - Don't unset the adjustments on the child on remove(), since they
      already existed or were autocreated on add()
    
      (We should what we are doing and set the adjustments of the
      scrollbars on the child rather than setting the adjustments of
      the child, so we match GTK+'s scrolllable interface, but this
      at least makes it consistent instead of a weird mix.)
    
    https://bugzilla.gnome.org/show_bug.cgi?id=611740

 src/st/st-box-layout.c  |    4 +-
 src/st/st-scroll-view.c |   68 ++++++++++++++++++++++++++++------------------
 2 files changed, 43 insertions(+), 29 deletions(-)
---
diff --git a/src/st/st-box-layout.c b/src/st/st-box-layout.c
index 45aed4b..17690f5 100644
--- a/src/st/st-box-layout.c
+++ b/src/st/st-box-layout.c
@@ -811,12 +811,12 @@ st_box_layout_allocate (ClutterActor          *actor,
   if (priv->is_vertical)
     {
       expand_amount = MAX (0, avail_height - natural_height);
-      shrink_amount = MAX (0, natural_height - MAX (avail_height, min_height));
+      shrink_amount = MAX (0, natural_height - avail_height);
     }
   else
     {
       expand_amount = MAX (0, avail_width - natural_width);
-      shrink_amount = MAX (0, natural_width - MAX (avail_width, min_width));
+      shrink_amount = MAX (0, natural_width - avail_width);
     }
 
   if (expand_amount > 0)
diff --git a/src/st/st-scroll-view.c b/src/st/st-scroll-view.c
index 8407e29..4c3a8a2 100644
--- a/src/st/st-scroll-view.c
+++ b/src/st/st-scroll-view.c
@@ -496,7 +496,7 @@ st_scroll_view_get_preferred_height (ClutterActor *actor,
       break;
     case GTK_POLICY_ALWAYS:
     case GTK_POLICY_AUTOMATIC:
-      /* Should theoretically use the min height of the hscrollbar,
+      /* Should theoretically use the min height of the vscrollbar,
        * but that's not cleanly defined at the moment */
       min_height = 0;
       break;
@@ -519,6 +519,18 @@ st_scroll_view_get_preferred_height (ClutterActor *actor,
   st_theme_node_adjust_preferred_height (theme_node, min_height_p, natural_height_p);
 }
 
+static gfloat
+get_shadow_height (ClutterActor *shadow)
+{
+  gfloat natural_height;
+
+  /* The shadows are empty StBin and have no height-for-width behavior */
+
+  clutter_actor_get_preferred_height (shadow, -1, NULL, &natural_height);
+
+  return natural_height;
+}
+
 static void
 st_scroll_view_allocate (ClutterActor          *actor,
                          const ClutterActorBox *box,
@@ -553,11 +565,11 @@ st_scroll_view_allocate (ClutterActor          *actor,
   sb_width = get_scrollbar_width (ST_SCROLL_VIEW (actor));
   sb_height = get_scrollbar_height (ST_SCROLL_VIEW (actor));
 
-  /* Determine what scrollbars are visible. The basic idea of the handling
-   * of an automatic scrollbars is that we start off with the assumption
-   * that that we don't need any scrollbars, see if that works, and if
-   * not add horizontal and vertical scrollbars until we are no longer
-   * overflowing.
+  /* Determine what scrollbars are visible. The basic idea of the
+   * handling of an automatic scrollbars is that we start off with the
+   * assumption that we don't need any scrollbars, see if that works,
+   * and if not add horizontal and vertical scrollbars until we are no
+   * longer overflowing.
    */
   if (priv->child)
     {
@@ -572,8 +584,7 @@ st_scroll_view_allocate (ClutterActor          *actor,
           if (priv->hscrollbar_policy == GTK_POLICY_AUTOMATIC)
             {
               /* Pass one, try without a vertical scrollbar */
-              clutter_actor_get_preferred_height (priv->child, MAX (avail_width, child_min_width),
-                                                  &child_min_height, NULL);
+              clutter_actor_get_preferred_height (priv->child, avail_width, &child_min_height, NULL);
               vscrollbar_visible = child_min_height > avail_height;
               hscrollbar_visible = child_min_width > avail_width - (vscrollbar_visible ? sb_width : 0);
               vscrollbar_visible = child_min_height > avail_height - (hscrollbar_visible ? sb_height : 0);
@@ -581,7 +592,7 @@ st_scroll_view_allocate (ClutterActor          *actor,
               /* Pass two - if we needed a vertical scrollbar, get a new preferred height */
               if (vscrollbar_visible)
                 {
-                  clutter_actor_get_preferred_height (priv->child, MAX (avail_width - sb_width, child_min_width),
+                  clutter_actor_get_preferred_height (priv->child, MAX (avail_width - sb_width, 0),
                                                       &child_min_height, NULL);
                   hscrollbar_visible = child_min_width > avail_width - sb_width;
                 }
@@ -591,8 +602,7 @@ st_scroll_view_allocate (ClutterActor          *actor,
               hscrollbar_visible = priv->hscrollbar_policy != GTK_POLICY_NEVER;
 
               /* try without a vertical scrollbar */
-              clutter_actor_get_preferred_height (priv->child, MAX (avail_width, child_min_width),
-                                                  &child_min_height, NULL);
+              clutter_actor_get_preferred_height (priv->child, avail_width, &child_min_height, NULL);
               vscrollbar_visible = child_min_height > avail_height - (hscrollbar_visible ? sb_height : 0);
             }
         }
@@ -608,8 +618,8 @@ st_scroll_view_allocate (ClutterActor          *actor,
     }
   else
     {
-      hscrollbar_visible = FALSE;
-      vscrollbar_visible = FALSE;
+      hscrollbar_visible = priv->hscrollbar_policy != GTK_POLICY_NEVER;
+      vscrollbar_visible = priv->vscrollbar_policy != GTK_POLICY_NEVER;
     }
 
   /* Whether or not we show the scrollbars, if the scrollbars are visible
@@ -656,22 +666,22 @@ st_scroll_view_allocate (ClutterActor          *actor,
   if (priv->child)
     clutter_actor_allocate (priv->child, &child_box, flags);
 
-  /*Shadows*/
+  /* Shadows */
   if (priv->top_shadow && CLUTTER_ACTOR_IS_VISIBLE (priv->top_shadow))
     {
       child_box.x1 = content_box.x1;
       child_box.y1 = content_box.y1;
       child_box.x2 = MAX (child_box.x1, content_box.x2 - sb_width);
-      child_box.y2 = content_box.y1 + clutter_actor_get_height (priv->top_shadow);
+      child_box.y2 = content_box.y1 + get_shadow_height (priv->top_shadow);
       clutter_actor_allocate (priv->top_shadow, &child_box, flags);
     }
 
   if (priv->bottom_shadow && CLUTTER_ACTOR_IS_VISIBLE (priv->bottom_shadow))
     {
       child_box.x1 = content_box.x1;
-      child_box.y1 = MAX (content_box.y1, content_box.y2 - sb_height - clutter_actor_get_height (priv->bottom_shadow));
+      child_box.y1 = content_box.y2 - sb_height - get_shadow_height (priv->bottom_shadow);
       child_box.x2 = MAX (content_box.x1, content_box.x2 - sb_width);
-      child_box.y2 = MAX (content_box.y1, content_box.y2 - sb_height);
+      child_box.y2 = content_box.y2 - sb_height;
       clutter_actor_allocate (priv->bottom_shadow, &child_box, flags);
     }
 
@@ -708,8 +718,8 @@ st_scroll_view_scroll_event (ClutterActor       *self,
   if (!priv->mouse_scroll)
     return FALSE;
 
-  hadjustment = st_scroll_bar_get_adjustment (ST_SCROLL_BAR(priv->hscroll));
-  vadjustment = st_scroll_bar_get_adjustment (ST_SCROLL_BAR(priv->vscroll));
+  hadjustment = st_scroll_bar_get_adjustment (ST_SCROLL_BAR (priv->hscroll));
+  vadjustment = st_scroll_bar_get_adjustment (ST_SCROLL_BAR (priv->vscroll));
 
   switch (event->direction)
     {
@@ -896,11 +906,11 @@ child_hadjustment_notify_cb (GObject      *gobject,
   disconnect_hadjustment (scroll);
 
   st_scrollable_get_adjustments (ST_SCROLLABLE (actor), &priv->hadjustment, NULL);
-  st_scroll_bar_set_adjustment (ST_SCROLL_BAR(priv->hscroll), priv->hadjustment);
+  st_scroll_bar_set_adjustment (ST_SCROLL_BAR (priv->hscroll), priv->hadjustment);
 
   if (priv->hadjustment)
     {
-      /* Force scroll step if neede. */
+      /* Force scroll step if needed. */
       if (priv->column_size_set)
         {
           g_object_set (priv->hadjustment,
@@ -920,12 +930,12 @@ child_vadjustment_notify_cb (GObject    *gobject,
 
   disconnect_vadjustment (scroll);
 
-  st_scrollable_get_adjustments (ST_SCROLLABLE(priv->child), NULL, &priv->vadjustment);
-  st_scroll_bar_set_adjustment (ST_SCROLL_BAR(priv->vscroll), priv->vadjustment);
+  st_scrollable_get_adjustments (ST_SCROLLABLE (priv->child), NULL, &priv->vadjustment);
+  st_scroll_bar_set_adjustment (ST_SCROLL_BAR (priv->vscroll), priv->vadjustment);
 
   if (priv->vadjustment)
     {
-      /* Force scroll step if neede. */
+      /* Force scroll step if needed. */
       if (priv->row_size_set)
         {
           g_object_set (priv->vadjustment,
@@ -937,8 +947,9 @@ child_vadjustment_notify_cb (GObject    *gobject,
                         G_CALLBACK (child_adjustment_changed_cb), scroll);
       g_signal_connect (priv->vadjustment, "notify::value",
                         G_CALLBACK (child_adjustment_notify_value), scroll);
-      update_shadow_visibility (scroll);
     }
+
+  update_shadow_visibility (scroll);
 }
 
 static void
@@ -997,7 +1008,8 @@ static void
 st_scroll_view_remove (ClutterContainer *container,
                        ClutterActor     *actor)
 {
-  StScrollViewPrivate *priv = ST_SCROLL_VIEW (container)->priv;
+  StScrollView *self = ST_SCROLL_VIEW (container);
+  StScrollViewPrivate *priv = self->priv;
 
   if (actor == priv->child)
     {
@@ -1006,13 +1018,15 @@ st_scroll_view_remove (ClutterContainer *container,
       /* chain up to StBin::remove() */
       st_scroll_view_parent_iface->remove (container, actor);
 
+      disconnect_hadjustment (self);
+      disconnect_vadjustment (self);
+
       g_signal_handlers_disconnect_by_func (priv->child,
                                             child_hadjustment_notify_cb,
                                             container);
       g_signal_handlers_disconnect_by_func (priv->child,
                                             child_vadjustment_notify_cb,
                                             container);
-      st_scrollable_set_adjustments ((StScrollable*) priv->child, NULL, NULL);
 
       g_object_unref (priv->child);
       priv->child = NULL;