/* dzl-bolding-label.c
*
* Copyright (C) 2016 Christian Hergert <chergert@redhat.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <glib/gi18n.h>
#include "dzl-bolding-label.h"
/**
* SECTION:dzl-bolding-label
*
* This is a GtkLabel widget that will allocate extra space if necessary
* so that the size request will not change when the contents of the
* label are bolded.
*
* This might be useful when you want to change a label based on some
* selection state without it affecting the size request or layout.
*/
struct _DzlBoldingLabel
{
GtkLabel parent_instance;
};
G_DEFINE_TYPE (DzlBoldingLabel, dzl_bolding_label, GTK_TYPE_LABEL)
enum {
PROP_0,
PROP_BOLD,
N_PROPS
};
static GParamSpec *properties [N_PROPS];
static void
dzl_bolding_label_get_preferred_width (GtkWidget *widget,
gint *min_width,
gint *nat_width)
{
const PangoFontDescription *font_desc;
PangoContext *context;
g_assert (DZL_IS_BOLDING_LABEL (widget));
g_assert (min_width);
g_assert (nat_width);
GTK_WIDGET_CLASS (dzl_bolding_label_parent_class)->get_preferred_width (widget, min_width, nat_width);
if (NULL == (context = gtk_widget_get_pango_context (widget)) ||
NULL == (font_desc = pango_context_get_font_description (context)))
return;
if (pango_font_description_get_weight (font_desc) != PANGO_WEIGHT_BOLD)
{
PangoFontDescription *font_desc_copy;
PangoLayout *layout;
const gchar *text;
PangoEllipsizeMode ellipsize;
gint height;
gint width;
text = gtk_label_get_text (GTK_LABEL (widget));
layout = gtk_widget_create_pango_layout (widget, text);
font_desc_copy = pango_font_description_copy (font_desc);
ellipsize = gtk_label_get_ellipsize (GTK_LABEL (widget));
pango_font_description_set_weight (font_desc_copy, PANGO_WEIGHT_BOLD);
pango_layout_set_font_description (layout, font_desc_copy);
pango_layout_set_ellipsize (layout, ellipsize);
pango_layout_get_pixel_size (layout, &width, &height);
if (ellipsize == PANGO_ELLIPSIZE_NONE)
{
/*
* Only apply min_width if we cannot ellipsize, if we can, that
* effects things differently.
*/
if (width > *min_width)
*min_width = width;
}
if (width > *nat_width)
*nat_width = width;
pango_font_description_free (font_desc_copy);
g_object_unref (layout);
}
}
static void
dzl_bolding_label_set_property (GObject *object,
guint prop_id,
const GValue *value,
GParamSpec *pspec)
{
DzlBoldingLabel *self = DZL_BOLDING_LABEL (object);
switch (prop_id)
{
case PROP_BOLD:
dzl_bolding_label_set_bold (self, g_value_get_boolean (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
}
}
static void
dzl_bolding_label_class_init (DzlBoldingLabelClass *klass)
{
GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);
GObjectClass *object_class = G_OBJECT_CLASS (klass);
object_class->set_property = dzl_bolding_label_set_property;
widget_class->get_preferred_width = dzl_bolding_label_get_preferred_width;
properties [PROP_BOLD] =
g_param_spec_boolean ("bold",
"Bold",
"Set the bold weight for the label",
FALSE,
(G_PARAM_WRITABLE | G_PARAM_STATIC_STRINGS));
g_object_class_install_properties (object_class, N_PROPS, properties);
}
static void
dzl_bolding_label_init (DzlBoldingLabel *self)
{
}
static gboolean
remove_weights (PangoAttribute *attr,
gpointer user_data)
{
return attr->klass->type == ((PangoAttribute *)user_data)->klass->type;
}
void
dzl_bolding_label_set_weight (DzlBoldingLabel *self,
PangoWeight weight)
{
PangoAttrList *filtered;
PangoAttrList *attrs;
PangoAttrList *copy;
PangoAttribute *attr;
g_return_if_fail (DZL_IS_BOLDING_LABEL (self));
attrs = gtk_label_get_attributes (GTK_LABEL (self));
if (attrs)
copy = pango_attr_list_copy (attrs);
else
copy = pango_attr_list_new ();
attr = pango_attr_weight_new (weight);
filtered = pango_attr_list_filter (copy, remove_weights, attr);
pango_attr_list_insert (copy, attr);
gtk_label_set_attributes (GTK_LABEL (self), copy);
gtk_widget_queue_draw (GTK_WIDGET (self));
pango_attr_list_unref (filtered);
pango_attr_list_unref (copy);
}
void
dzl_bolding_label_set_bold (DzlBoldingLabel *self,
gboolean bold)
{
g_return_if_fail (DZL_IS_BOLDING_LABEL (self));
dzl_bolding_label_set_weight (self, bold ? PANGO_WEIGHT_BOLD : PANGO_WEIGHT_NORMAL);
}