[gtk+/wip/baseline: 6/7] GtkButton: Add baseline align support

[Alexander Larsson <alexl src gnome org>]

commit fe2062925c5a194b111f52519eac6bdacf972f72
Author: Alexander Larsson <alexl redhat com>
Date:   Thu Mar 7 13:53:16 2013 +0100

    GtkButton: Add baseline align support

 gtk/gtkbutton.c |   62 ++++++++++++++++++++++++++++++++++++++++++++++++------
 1 files changed, 55 insertions(+), 7 deletions(-)
---
diff --git a/gtk/gtkbutton.c b/gtk/gtkbutton.c
index 3ac36a7..5165ba4 100644
--- a/gtk/gtkbutton.c
+++ b/gtk/gtkbutton.c
@@ -170,6 +170,12 @@ static void gtk_button_get_preferred_width       (GtkWidget           *widget,
 static void gtk_button_get_preferred_height      (GtkWidget           *widget,
                                                  gint                *minimum_size,
                                                  gint                *natural_size);
+static void gtk_button_get_preferred_height_and_baseline_for_width (GtkWidget *widget,
+                                                                   gint       width,
+                                                                   gint      *minimum_size,
+                                                                   gint      *natural_size,
+                                                                   gint      *minimum_baseline,
+                                                                   gint      *natural_baseline);
   
 static guint button_signals[LAST_SIGNAL] = { 0 };
 
@@ -196,6 +202,7 @@ gtk_button_class_init (GtkButtonClass *klass)
 
   widget_class->get_preferred_width  = gtk_button_get_preferred_width;
   widget_class->get_preferred_height = gtk_button_get_preferred_height;
+  widget_class->get_preferred_height_and_baseline_for_width = 
gtk_button_get_preferred_height_and_baseline_for_width;
   widget_class->destroy = gtk_button_destroy;
   widget_class->screen_changed = gtk_button_screen_changed;
   widget_class->realize = gtk_button_realize;
@@ -1150,11 +1157,15 @@ gtk_button_construct_child (GtkButton *button)
       else
        box = gtk_box_new (GTK_ORIENTATION_VERTICAL, image_spacing);
 
+      gtk_widget_set_valign (box, GTK_ALIGN_BASELINE);
+
       if (priv->align_set)
        align = gtk_alignment_new (priv->xalign, priv->yalign, 0.0, 0.0);
       else
        align = gtk_alignment_new (0.5, 0.5, 0.0, 0.0);
 
+      gtk_widget_set_valign (align, GTK_ALIGN_BASELINE);
+
       if (priv->image_position == GTK_POS_LEFT ||
          priv->image_position == GTK_POS_TOP)
        gtk_box_pack_start (GTK_BOX (box), priv->image, FALSE, FALSE, 0);
@@ -1172,6 +1183,8 @@ gtk_button_construct_child (GtkButton *button)
           else
             label = gtk_label_new (label_text);
 
+         gtk_widget_set_valign (label, GTK_ALIGN_BASELINE);
+
          if (priv->image_position == GTK_POS_RIGHT ||
              priv->image_position == GTK_POS_BOTTOM)
            gtk_box_pack_start (GTK_BOX (box), label, FALSE, FALSE, 0);
@@ -1196,6 +1209,8 @@ gtk_button_construct_child (GtkButton *button)
   else
     label = gtk_label_new (priv->label_text);
 
+  gtk_widget_set_valign (label, GTK_ALIGN_BASELINE);
+
   if (priv->align_set)
     gtk_misc_set_alignment (GTK_MISC (label), priv->xalign, priv->yalign);
 
@@ -1584,6 +1599,7 @@ gtk_button_size_allocate (GtkWidget     *widget,
   GtkBorder border;
   gint focus_width;
   gint focus_pad;
+  gint baseline;
 
   context = gtk_widget_get_style_context (widget);
 
@@ -1651,7 +1667,10 @@ gtk_button_size_allocate (GtkWidget     *widget,
       child_allocation.width  = MAX (1, child_allocation.width);
       child_allocation.height = MAX (1, child_allocation.height);
 
-      gtk_widget_size_allocate (child, &child_allocation);
+      baseline = gtk_widget_get_allocated_baseline (widget);
+      if (baseline != -1)
+       baseline -= child_allocation.y - allocation->y;
+      gtk_widget_size_allocate_with_baseline (child, &child_allocation, baseline);
     }
 }
 
@@ -2063,7 +2082,9 @@ static void
 gtk_button_get_size (GtkWidget      *widget,
                     GtkOrientation  orientation,
                     gint           *minimum_size,
-                    gint           *natural_size)
+                    gint           *natural_size,
+                    gint           *minimum_baseline,
+                    gint           *natural_baseline)
 {
   GtkButton *button = GTK_BUTTON (widget);
   GtkStyleContext *context;
@@ -2074,6 +2095,7 @@ gtk_button_get_size (GtkWidget      *widget,
   gint focus_width;
   gint focus_pad;
   gint minimum, natural;
+  gint top_offset;
 
   context = gtk_widget_get_style_context (widget);
 
@@ -2084,6 +2106,8 @@ gtk_button_get_size (GtkWidget      *widget,
                                "focus-padding", &focus_pad,
                                NULL);
 
+  top_offset = 0;
+
   if (orientation == GTK_ORIENTATION_HORIZONTAL)
     {
       minimum = padding.left + padding.right +
@@ -2097,9 +2121,14 @@ gtk_button_get_size (GtkWidget      *widget,
       minimum = padding.top + padding.bottom +
         border.top + border.bottom;
 
+      top_offset = padding.top + border.top + focus_width + focus_pad;
+
       if (gtk_widget_get_can_default (GTK_WIDGET (widget)))
-       minimum += default_border.top + default_border.bottom;
-    }  
+       {
+         minimum += default_border.top + default_border.bottom;
+         top_offset += default_border.top;
+       }
+    }
 
   minimum += 2 * (focus_width + focus_pad);
   natural = minimum;
@@ -2108,11 +2137,17 @@ gtk_button_get_size (GtkWidget      *widget,
       gtk_widget_get_visible (child))
     {
       gint child_min, child_nat;
+      gint child_min_baseline = -1, child_nat_baseline = -1;
 
       if (orientation == GTK_ORIENTATION_HORIZONTAL)
        gtk_widget_get_preferred_width (child, &child_min, &child_nat);
       else
-       gtk_widget_get_preferred_height (child, &child_min, &child_nat);
+       gtk_widget_get_preferred_height_and_baseline_for_width (child, -1, &child_min, &child_nat, 
&child_min_baseline, &child_nat_baseline);
+
+      if (minimum_baseline && child_min_baseline >= 0)
+       *minimum_baseline = child_min_baseline + top_offset;
+      if (natural_baseline && child_nat_baseline >= 0)
+       *natural_baseline = child_nat_baseline + top_offset;
 
       minimum += child_min;
       natural += child_nat;
@@ -2130,7 +2165,7 @@ gtk_button_get_preferred_width (GtkWidget *widget,
                                 gint      *minimum_size,
                                 gint      *natural_size)
 {
-  gtk_button_get_size (widget, GTK_ORIENTATION_HORIZONTAL, minimum_size, natural_size);
+  gtk_button_get_size (widget, GTK_ORIENTATION_HORIZONTAL, minimum_size, natural_size, NULL, NULL);
 }
 
 static void 
@@ -2138,7 +2173,20 @@ gtk_button_get_preferred_height (GtkWidget *widget,
                                  gint      *minimum_size,
                                  gint      *natural_size)
 {
-  gtk_button_get_size (widget, GTK_ORIENTATION_VERTICAL, minimum_size, natural_size);
+  gtk_button_get_size (widget, GTK_ORIENTATION_VERTICAL, minimum_size, natural_size, NULL, NULL);
+}
+
+static void
+gtk_button_get_preferred_height_and_baseline_for_width (GtkWidget *widget,
+                                                       gint       width,
+                                                       gint      *minimum_size,
+                                                       gint      *natural_size,
+                                                       gint      *minimum_baseline,
+                                                       gint      *natural_baseline)
+{
+  /* GtkButton is GTK_SIZE_REQUEST_CONSTANT mode, so width will be -1 all the time */
+  g_assert (width == -1);
+  gtk_button_get_size (widget, GTK_ORIENTATION_VERTICAL, minimum_size, natural_size, minimum_baseline, 
natural_baseline);
 }
 
 /**