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
PangoContext
that can be used with theGtkPrintContext
.
- create_pango_layout() Layout #
Creates a new
PangoLayout
that 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
GtkPageSetup
that determines the page dimensions of theGtkPrintContext
.
- get_pango_fontmap() FontMap #
Returns a
PangoFontMap
that 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
cr
dpi_y – the vertical resolution to use with
cr