[gtk+] fontchooser: Rewrite size changes

[Benjamin Otte <otte src gnome org>]

commit fe8ed0a3f6f3012b3cc9e902b504b886bb61b0b6
Author: Benjamin Otte <otte redhat com>
Date:   Tue Sep 20 01:17:29 2011 +0200

    fontchooser: Rewrite size changes
    
    They now go through gtk_font_chooser_widget_take_font_desc(). The end
    goal is to make all changes go through this function, so that all
    updates that are happening are easy to track.
    
    Another change is that the code now merges the font description instead
    of just using the new one. This avoids weird situations when people set
    the font "Bold" for example, which has neither a size nor a font family.

 gtk/gtkfontchooserwidget.c |   77 ++++++++++++++++++++-----------------------
 1 files changed, 36 insertions(+), 41 deletions(-)
---
diff --git a/gtk/gtkfontchooserwidget.c b/gtk/gtkfontchooserwidget.c
index 757ed27..012c85f 100644
--- a/gtk/gtkfontchooserwidget.c
+++ b/gtk/gtkfontchooserwidget.c
@@ -292,45 +292,21 @@ icon_press_cb (GtkEntry             *entry,
 }
 
 static void
-slider_change_cb (GtkAdjustment *adjustment,
-                  gpointer       user_data)
-{
-  GtkFontChooserWidget        *fc    = (GtkFontChooserWidget*)user_data;
-  GtkFontChooserWidgetPrivate *priv  = fc->priv;
-  GtkAdjustment         *spin_adj     = gtk_spin_button_get_adjustment(GTK_SPIN_BUTTON (priv->size_spin));
-  gdouble                slider_value = gtk_adjustment_get_value (adjustment);
-  gdouble                spin_value   = gtk_adjustment_get_value (spin_adj);
-
-  if (slider_value != spin_value)
-    gtk_adjustment_set_value (spin_adj,
-                              gtk_adjustment_get_value (adjustment));
-}
-
-static void
-spin_change_cb (GtkAdjustment *adjustment,
+size_change_cb (GtkAdjustment *adjustment,
                 gpointer       user_data)
 {
-  PangoFontDescription    *desc;
-  GtkFontChooserWidget          *fontchooser = (GtkFontChooserWidget*)user_data;
-  GtkFontChooserWidgetPrivate   *priv        = fontchooser->priv;
-  GtkAdjustment           *slider_adj  = gtk_range_get_adjustment (GTK_RANGE (priv->size_slider));
+  GtkFontChooserWidget *fontchooser = user_data;
+  GtkFontChooserWidgetPrivate *priv = fontchooser->priv;
+  PangoFontDescription *font_desc;
   gdouble size = gtk_adjustment_get_value (adjustment);
 
-  desc = pango_context_get_font_description (gtk_widget_get_pango_context (priv->preview));
-  pango_font_description_set_size (desc, ((gint)size) * PANGO_SCALE);
-  gtk_widget_override_font (priv->preview, desc);
-
+  font_desc = pango_font_description_new ();
   if (pango_font_description_get_size_is_absolute (priv->font_desc))
-    pango_font_description_set_absolute_size (priv->font_desc, size * PANGO_SCALE);
+    pango_font_description_set_absolute_size (font_desc, size * PANGO_SCALE);
   else
-    pango_font_description_set_size (priv->font_desc, size * PANGO_SCALE);
+    pango_font_description_set_size (font_desc, size * PANGO_SCALE);
 
-  gtk_adjustment_set_value (slider_adj, size);
-
-  gtk_widget_queue_draw (priv->preview);
-
-  g_object_notify (G_OBJECT (fontchooser), "font");
-  g_object_notify (G_OBJECT (fontchooser), "font-desc");
+  gtk_font_chooser_widget_take_font_desc (fontchooser, font_desc);
 }
 
 static void
@@ -509,6 +485,7 @@ gtk_font_chooser_widget_init (GtkFontChooserWidget *fontchooser)
   /* Default preview string  */
   priv->preview_text = g_strdup (pango_language_get_sample_string (NULL));
   priv->show_preview_entry = TRUE;
+  priv->font_desc = pango_font_description_new ();
 
   gtk_widget_push_composite_child ();
 
@@ -600,9 +577,9 @@ gtk_font_chooser_widget_init (GtkFontChooserWidget *fontchooser)
                     "icon-press", G_CALLBACK (icon_press_cb), NULL);
 
   g_signal_connect (gtk_range_get_adjustment (GTK_RANGE (priv->size_slider)),
-                    "value-changed", G_CALLBACK (slider_change_cb), fontchooser);
+                    "value-changed", G_CALLBACK (size_change_cb), fontchooser);
   g_signal_connect (gtk_spin_button_get_adjustment (GTK_SPIN_BUTTON (priv->size_spin)),
-                    "value-changed", G_CALLBACK (spin_change_cb), fontchooser);
+                    "value-changed", G_CALLBACK (size_change_cb), fontchooser);
 
   g_signal_connect (priv->family_face_list, "cursor-changed",
                     G_CALLBACK (cursor_changed_cb), fontchooser);
@@ -971,6 +948,7 @@ gtk_font_chooser_widget_take_font_desc (GtkFontChooserWidget *fontchooser,
                                         PangoFontDescription *font_desc)
 {
   GtkFontChooserWidgetPrivate *priv = fontchooser->priv;
+  PangoFontMask mask;
 
   if (font_desc && priv->font_desc &&
       pango_font_description_equal (font_desc, priv->font_desc))
@@ -979,14 +957,31 @@ gtk_font_chooser_widget_take_font_desc (GtkFontChooserWidget *fontchooser,
       return;
     }
 
-  if (priv->font_desc)
-    pango_font_description_free (priv->font_desc);
-  if (font_desc)
-    priv->font_desc = font_desc; /* adopted */
-  else
-    priv->font_desc = pango_font_description_from_string (GTK_FONT_CHOOSER_DEFAULT_FONT_NAME);
+  if (font_desc == NULL)
+    font_desc = pango_font_description_from_string (GTK_FONT_CHOOSER_DEFAULT_FONT_NAME);
 
-  gtk_font_chooser_widget_select_font (fontchooser);
+  pango_font_description_merge (priv->font_desc, font_desc, TRUE);
+
+  mask = pango_font_description_get_set_fields (font_desc);
+  
+  if (mask & PANGO_FONT_MASK_SIZE)
+    {
+      double font_size = (double) pango_font_description_get_size (priv->font_desc) / PANGO_SCALE;
+      /* XXX: This clamps, which can cause it to reloop into here, do we need
+       * to block its signal handler? */
+      gtk_range_set_value (GTK_RANGE (priv->size_slider), font_size);
+      gtk_spin_button_set_value (GTK_SPIN_BUTTON (priv->size_spin), font_size);
+    }
+  if (mask & (PANGO_FONT_MASK_FAMILY | PANGO_FONT_MASK_STYLE | PANGO_FONT_MASK_VARIANT |
+              PANGO_FONT_MASK_WEIGHT | PANGO_FONT_MASK_STRETCH))
+    gtk_font_chooser_widget_select_font (fontchooser);
+
+  gtk_widget_override_font (priv->preview, priv->font_desc);
+
+  pango_font_description_free (font_desc); /* adopted */
+
+  g_object_notify (G_OBJECT (fontchooser), "font");
+  g_object_notify (G_OBJECT (fontchooser), "font-desc");
 }
 
 static void