GtkLabel::set_attributes
void set_attributes(
      PangoAttrList list
     );
    Sets the Pango attributes for the label to those defined by list. The attributes set by list will be ignored if either use_underline or user_markup is true.
Пример 79. Setting a List of Pango Attributes for a GtkLabel
<?php
// Create a window to hold the label.
$window = new GtkWindow();
// Set up the window to close cleanly.
$window->connect_simple('destroy', array('Gtk', 'main_quit'));
// Create a label
$label = new GtkLabel('Bold Label');
// Create a Pango attribute list.
$list = new PangoAttrList();
// Create a bold Pango weight attribute.
$attr = new PangoAttrInt(Pango::ATTR_WEIGHT, Pango::WEIGHT_BOLD);
// Add the attribute to the list.
$list->insert($attr);
// Set the attributes for the label.
$label->set_attributes($list);
// Add the label to the window.
$window->add($label);
// Show the window and start the main loop.
$window->show_all();
Gtk::main();
?>
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Виж също: get_attributes()