PrintContext#
Superclasses: Object
A GtkPrintContext encapsulates context information that is required when
drawing pages for printing.
This includes the cairo context and important parameters like page size
and resolution. It also lets you easily create Layout and
Context objects that match the font metrics of the cairo surface.
GtkPrintContext objects get passed to the
begin_print,
end_print,
request_page_setup and
draw_page signals on the
PrintOperation object.
Using GtkPrintContext in a ::draw-page callback#
static void
draw_page (GtkPrintOperation *operation,
GtkPrintContext *context,
int page_nr)
{
cairo_t *cr;
PangoLayout *layout;
PangoFontDescription *desc;
cr = gtk_print_context_get_cairo_context (context);
// Draw a red rectangle, as wide as the paper (inside the margins)
cairo_set_source_rgb (cr, 1.0, 0, 0);
cairo_rectangle (cr, 0, 0, gtk_print_context_get_width (context), 50);
cairo_fill (cr);
// Draw some lines
cairo_move_to (cr, 20, 10);
cairo_line_to (cr, 40, 20);
cairo_arc (cr, 60, 60, 20, 0, M_PI);
cairo_line_to (cr, 80, 20);
cairo_set_source_rgb (cr, 0, 0, 0);
cairo_set_line_width (cr, 5);
cairo_set_line_cap (cr, CAIRO_LINE_CAP_ROUND);
cairo_set_line_join (cr, CAIRO_LINE_JOIN_ROUND);
cairo_stroke (cr);
// Draw some text
layout = gtk_print_context_create_pango_layout (context);
pango_layout_set_text (layout, "Hello World! Printing is easy", -1);
desc = pango_font_description_from_string ("sans 28");
pango_layout_set_font_description (layout, desc);
pango_font_description_free (desc);
cairo_move_to (cr, 30, 20);
pango_cairo_layout_path (cr, layout);
// Font Outline
cairo_set_source_rgb (cr, 0.93, 1.0, 0.47);
cairo_set_line_width (cr, 0.5);
cairo_stroke_preserve (cr);
// Font Fill
cairo_set_source_rgb (cr, 0, 0.0, 1.0);
cairo_fill (cr);
g_object_unref (layout);
}
Methods#
- class PrintContext
- create_pango_context() Context#
Creates a new
PangoContextthat can be used with theGtkPrintContext.
- create_pango_layout() Layout#
Creates a new
PangoLayoutthat is suitable for use with theGtkPrintContext.
- get_cairo_context() Context#
Obtains the cairo context that is associated with the
GtkPrintContext.
- get_hard_margins() tuple[bool, float, float, float, float]#
Obtains the hardware printer margins of the
GtkPrintContext, in units.
- get_page_setup() PageSetup#
Obtains the
GtkPageSetupthat determines the page dimensions of theGtkPrintContext.
- get_pango_fontmap() FontMap#
Returns a
PangoFontMapthat is suitable for use with theGtkPrintContext.
- set_cairo_context(cr: Context, dpi_x: float, dpi_y: float) None#
Sets a new cairo context on a print context.
This function is intended to be used when implementing an internal print preview, it is not needed for printing, since GTK itself creates a suitable cairo context in that case.
- Parameters:
cr – the cairo context
dpi_x – the horizontal resolution to use with
crdpi_y – the vertical resolution to use with
cr