From 85a55b2921ab7621d839c5391c1a489f572362f9 Mon Sep 17 00:00:00 2001
From: Tristan Van Berkom <tristan.van.berkom@gmail.com>
Date: Tue, 6 Apr 2010 20:47:15 -0400
Subject: [PATCH] Implement GtkExtendedLayout on Alignment

GtkAlignment is already using the height for width api to align
the child in the cases where space is available, but also needed
to implement the extended layout in order to reflect natural sizes
to parent widgets.
---
 gtk/gtkalignment.c | 82 ++++++++++++++++++++++++++++------------------
 1 file changed, 50 insertions(+), 32 deletions(-)

diff --git a/gtk/gtkalignment.c b/gtk/gtkalignment.c
index 3accb4ddb7..55a210d705 100644
--- a/gtk/gtkalignment.c
+++ b/gtk/gtkalignment.c
@@ -55,8 +55,6 @@ struct _GtkAlignmentPrivate
   guint padding_right;
 };
 
-static void gtk_alignment_size_request  (GtkWidget         *widget,
-					 GtkRequisition    *requisition);
 static void gtk_alignment_size_allocate (GtkWidget         *widget,
 					 GtkAllocation     *allocation);
 static void gtk_alignment_set_property (GObject         *object,
@@ -68,7 +66,14 @@ static void gtk_alignment_get_property (GObject         *object,
                                         GValue          *value,
                                         GParamSpec      *pspec);
 
-G_DEFINE_TYPE (GtkAlignment, gtk_alignment, GTK_TYPE_BIN)
+static void gtk_alignment_extended_layout_init      (GtkExtendedLayoutIface *iface);
+static void gtk_alignment_get_desired_size          (GtkExtendedLayout      *layout,
+						     GtkRequisition         *minimum_size,
+						     GtkRequisition         *natural_size);
+
+G_DEFINE_TYPE_WITH_CODE (GtkAlignment, gtk_alignment, GTK_TYPE_BIN,
+			 G_IMPLEMENT_INTERFACE (GTK_TYPE_EXTENDED_LAYOUT,
+						gtk_alignment_extended_layout_init))
 
 static void
 gtk_alignment_class_init (GtkAlignmentClass *class)
@@ -82,7 +87,6 @@ gtk_alignment_class_init (GtkAlignmentClass *class)
   gobject_class->set_property = gtk_alignment_set_property;
   gobject_class->get_property = gtk_alignment_get_property;
 
-  widget_class->size_request = gtk_alignment_size_request;
   widget_class->size_allocate = gtk_alignment_size_allocate;
 
   g_object_class_install_property (gobject_class,
@@ -409,34 +413,6 @@ gtk_alignment_set (GtkAlignment *alignment,
 }
 
 
-static void
-gtk_alignment_size_request (GtkWidget      *widget,
-			    GtkRequisition *requisition)
-{
-  GtkBin *bin;
-  GtkAlignmentPrivate *priv;
-
-  bin = GTK_BIN (widget);
-  priv = GTK_ALIGNMENT_GET_PRIVATE (widget);
-
-  requisition->width = GTK_CONTAINER (widget)->border_width * 2;
-  requisition->height = GTK_CONTAINER (widget)->border_width * 2;
-
-  if (bin->child && gtk_widget_get_visible (bin->child))
-    {
-      GtkRequisition child_requisition;
-      
-      gtk_widget_size_request (bin->child, &child_requisition);
-
-      requisition->width += child_requisition.width;
-      requisition->height += child_requisition.height;
-
-      /* Request extra space for the padding: */
-      requisition->width += (priv->padding_left + priv->padding_right);
-      requisition->height += (priv->padding_top + priv->padding_bottom);
-    }
-}
-
 static void
 gtk_alignment_size_allocate (GtkWidget     *widget,
 			     GtkAllocation *allocation)
@@ -504,6 +480,48 @@ gtk_alignment_size_allocate (GtkWidget     *widget,
     }
 }
 
+
+static void
+gtk_alignment_extended_layout_init (GtkExtendedLayoutIface *iface)
+{
+  iface->get_desired_size = gtk_alignment_get_desired_size;
+}
+
+static void
+gtk_alignment_get_desired_size (GtkExtendedLayout *layout,
+				GtkRequisition    *minimum_size,
+				GtkRequisition    *natural_size)
+{
+  GtkWidget *child;
+  GtkAlignmentPrivate *priv;
+
+  priv = GTK_ALIGNMENT_GET_PRIVATE (layout);
+
+  minimum_size->width = GTK_CONTAINER (layout)->border_width * 2;
+  minimum_size->height = GTK_CONTAINER (layout)->border_width * 2;
+
+  *natural_size = *minimum_size;
+
+  if ((child = gtk_bin_get_child (GTK_BIN (layout))) && gtk_widget_get_visible (child))
+    {
+      GtkRequisition child_min, child_nat;
+
+      /* Request extra space for the padding: */
+      minimum_size->width  += (priv->padding_left + priv->padding_right);
+      minimum_size->height += (priv->padding_top + priv->padding_bottom);
+
+      *natural_size = *minimum_size;
+
+      gtk_extended_layout_get_desired_size (GTK_EXTENDED_LAYOUT (child), 
+					    &child_min, &child_nat);
+
+      minimum_size->width  += child_min.width;
+      minimum_size->height += child_min.height;
+      natural_size->width  += child_nat.width;
+      natural_size->height += child_nat.height;
+    }
+}
+
 /**
  * gtk_alignment_set_padding:
  * @alignment: a #GtkAlignment