[gnumeric] GUI: Center notebook tabs.

[Morten Welinder <mortenw src gnome org>]

commit c1f7688721e7bc726e3bd4ae1893d662b2bafeb9
Author: Morten Welinder <terra gnome org>
Date:   Wed Apr 3 18:40:50 2013 -0400

    GUI: Center notebook tabs.

 src/widgets/ChangeLog      |    1 +
 src/widgets/gnm-notebook.c |   49 ++++++++++++++++++++++++++++---------------
 2 files changed, 33 insertions(+), 17 deletions(-)
---
diff --git a/src/widgets/ChangeLog b/src/widgets/ChangeLog
index c17600f..4687cc9 100644
--- a/src/widgets/ChangeLog
+++ b/src/widgets/ChangeLog
@@ -4,6 +4,7 @@
        notebook tab.
        (gnm_notebook_button_set_property): Clear the layouts for
        background changes.
+       (gnm_notebook_button_draw): Center label within allocation.
 
        * Makefile.am: Remove editable-widget.
 
diff --git a/src/widgets/gnm-notebook.c b/src/widgets/gnm-notebook.c
index 3439d78..227e1d0 100644
--- a/src/widgets/gnm-notebook.c
+++ b/src/widgets/gnm-notebook.c
@@ -37,6 +37,7 @@ struct GnmNotebookButton_ {
        PangoLayout *layout;
        PangoLayout *layout_active;
 
+       PangoRectangle logical, logical_active;
        int x_offset, x_offset_active;
 
        GdkRGBA *fg, *bg;
@@ -104,17 +105,20 @@ gnm_notebook_button_ensure_layout (GnmNotebookButton *nbb)
        const char *text = gtk_label_get_text (GTK_LABEL (nbb));
 
        if (nbb->layout) {
-               /* Optimize?  */
+               if (strcmp (text, pango_layout_get_text (nbb->layout)) == 0)
+                       return;
                pango_layout_set_text (nbb->layout, text, -1);
                pango_layout_set_text (nbb->layout_active, text, -1);
        } else {
                PangoAttrList *attrs, *attrs_active;
                PangoAttribute *attr;
                PangoFontDescription *desc;
-               GtkStyleContext *context = gtk_widget_get_style_context (GTK_WIDGET (nbb));
+               GtkWidget *widget = GTK_WIDGET (nbb);
+               GtkStyleContext *context =
+                       gtk_widget_get_style_context (widget);
 
-               nbb->layout = gtk_widget_create_pango_layout (GTK_WIDGET (nbb), text);
-               nbb->layout_active = gtk_widget_create_pango_layout (GTK_WIDGET (nbb), text);
+               nbb->layout = gtk_widget_create_pango_layout (widget, text);
+               nbb->layout_active = gtk_widget_create_pango_layout (widget, text);
 
                /* Common */
                attrs = pango_attr_list_new ();
@@ -150,6 +154,9 @@ gnm_notebook_button_ensure_layout (GnmNotebookButton *nbb)
                pango_layout_set_attributes (nbb->layout_active, attrs_active);
                pango_attr_list_unref (attrs_active);
        }
+
+       pango_layout_get_extents (nbb->layout, NULL, &nbb->logical);
+       pango_layout_get_extents (nbb->layout_active, NULL, &nbb->logical_active);
 }
 
 static void
@@ -199,7 +206,6 @@ gnm_notebook_button_get_preferred_height (GtkWidget *widget,
                                          gint      *natural)
 {
        GnmNotebookButton *nbb = GNM_NOTEBOOK_BUTTON (widget);
-       PangoRectangle logical, logical_active;
        GtkBorder padding;
 
        gtk_style_context_get_padding (gtk_widget_get_style_context (widget),
@@ -207,12 +213,11 @@ gnm_notebook_button_get_preferred_height (GtkWidget *widget,
                                       &padding);
 
        gnm_notebook_button_ensure_layout (nbb);
-       pango_layout_get_extents (nbb->layout, NULL, &logical);
-       pango_layout_get_extents (nbb->layout_active, NULL, &logical_active);
 
        *minimum = *natural =
                (padding.top +
-                PANGO_PIXELS_CEIL (MAX (logical.height, logical_active.height)) +
+                PANGO_PIXELS_CEIL (MAX (nbb->logical.height,
+                                        nbb->logical_active.height)) +
                 padding.bottom);
 }
 
@@ -222,29 +227,38 @@ gnm_notebook_button_get_preferred_width (GtkWidget *widget,
                                         gint      *natural)
 {
        GnmNotebookButton *nbb = GNM_NOTEBOOK_BUTTON (widget);
-       PangoRectangle logical, logical_active;
        GtkBorder padding;
-       int dx;
 
        gtk_style_context_get_padding (gtk_widget_get_style_context (widget),
                                       GTK_STATE_FLAG_NORMAL,
                                       &padding);
 
        gnm_notebook_button_ensure_layout (nbb);
-       pango_layout_get_extents (nbb->layout, NULL, &logical);
-       pango_layout_get_extents (nbb->layout_active, NULL, &logical_active);
-
-       dx = logical_active.width - logical.width;
-       nbb->x_offset = PANGO_PIXELS (MAX (0, dx / 2));
-       nbb->x_offset_active = PANGO_PIXELS (MAX (0, -dx / 2));
 
        *minimum = *natural =
                (padding.left +
-                PANGO_PIXELS_CEIL (MAX (logical.width, logical_active.width)) +
+                PANGO_PIXELS_CEIL (MAX (nbb->logical.width,
+                                        nbb->logical_active.width)) +
                 padding.right);
 }
 
 static void
+gnm_notebook_button_size_allocate (GtkWidget     *widget,
+                                  GtkAllocation *allocation)
+{
+       GnmNotebookButton *nbb = GNM_NOTEBOOK_BUTTON (widget);
+
+       gnm_notebook_button_ensure_layout (nbb);
+       nbb->x_offset =
+               (allocation->width - PANGO_PIXELS (nbb->logical.width)) / 2;
+       nbb->x_offset_active =
+               (allocation->width - PANGO_PIXELS (nbb->logical_active.width)) / 2;
+
+       GTK_WIDGET_CLASS(gnm_notebook_button_parent_class)
+               ->size_allocate (widget, allocation);
+}
+
+static void
 gnm_notebook_button_class_init (GObjectClass *klass)
 {
        GtkWidgetClass *wclass = (GtkWidgetClass *)klass;
@@ -275,6 +289,7 @@ gnm_notebook_button_class_init (GObjectClass *klass)
        wclass->get_request_mode = gnm_notebook_button_get_request_mode;
        wclass->get_preferred_width = gnm_notebook_button_get_preferred_width;
        wclass->get_preferred_height = gnm_notebook_button_get_preferred_height;
+       wclass->size_allocate = gnm_notebook_button_size_allocate;
 }
 
 static void