struct Gtk::PrintOperation::DrawPageSignal

Overview

Emitted for every page that is printed.

The signal handler must render the @page_nr's page onto the cairo context obtained from @context using Gtk::PrintContext#cairo_context.

WARNING ⚠️ The following code is in c ⚠️

static void
draw_page (GtkPrintOperation *operation,
           GtkPrintContext   *context,
           int                page_nr,
           gpointer           user_data)
{
  cairo_t *cr;
  PangoLayout *layout;
  double width, text_height;
  int layout_height;
  PangoFontDescription *desc;

  cr = gtk_print_context_get_cairo_context (context);
  width = gtk_print_context_get_width (context);

  cairo_rectangle (cr, 0, 0, width, HEADER_HEIGHT);

  cairo_set_source_rgb (cr, 0.8, 0.8, 0.8);
  cairo_fill (cr);

  layout = gtk_print_context_create_pango_layout (context);

  desc = pango_font_description_from_string ("sans 14");
  pango_layout_set_font_description (layout, desc);
  pango_font_description_free (desc);

  pango_layout_set_text (layout, "some text", -1);
  pango_layout_set_width (layout, width * PANGO_SCALE);
  pango_layout_set_alignment (layout, PANGO_ALIGN_CENTER);

  pango_layout_get_size (layout, NULL, &layout_height);
  text_height = (double)layout_height / PANGO_SCALE;

  cairo_move_to (cr, width / 2,  (HEADER_HEIGHT - text_height) / 2);
  pango_cairo_show_layout (cr, layout);

  g_object_unref (layout);
}

Use Gtk::PrintOperation#use_full_page= and Gtk::PrintOperation#unit= before starting the print operation to set up the transformation of the cairo context according to your needs.

Defined in:

lib/gi-crystal/src/auto/gtk-4.0/print_operation.cr

Instance Method Summary

Instance methods inherited from struct GObject::Signal

[](detail : String) : self [], name : String name

Constructor methods inherited from struct GObject::Signal

new(source : GObject::Object, detail : String? = nil) new

Instance Method Detail

def connect(*, after : Bool = false, &block : Proc(Gtk::PrintContext, Int32, Nil)) : GObject::SignalConnection #

def connect(handler : Proc(Gtk::PrintContext, Int32, Nil), *, after : Bool = false) : GObject::SignalConnection #

def connect(handler : Proc(Gtk::PrintOperation, Gtk::PrintContext, Int32, Nil), *, after : Bool = false) : GObject::SignalConnection #

def emit(context : Gtk::PrintContext, page_nr : Int32) : Nil #

def name : String #
Description copied from struct GObject::Signal

The signal name