GtkPrintContext

GtkPrintContext — Encapsulates context for drawing pages

Types and Values

Object Hierarchy

    GObject
    ╰── GtkPrintContext

Includes

#include <gtk/gtk.h>

Description

A GtkPrintContext encapsulates context information that is required when drawing pages for printing, such as the cairo context and important parameters like page size and resolution. It also lets you easily create PangoLayout and PangoContext objects that match the font metrics of the cairo surface.

GtkPrintContext objects gets passed to the “begin-print”, “end-print”, “request-page-setup” and “draw-page” signals on the GtkPrintOperation.

Using GtkPrintContext in a “draw-page” callback

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
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_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);
}

Printing support was added in GTK+ 2.10.

Functions

gtk_print_context_get_cairo_context ()

cairo_t *
gtk_print_context_get_cairo_context (GtkPrintContext *context);

Obtains the cairo context that is associated with the GtkPrintContext.

Parameters

context

a GtkPrintContext

 

Returns

the cairo context of context .

[transfer none]

Since: 2.10


gtk_print_context_set_cairo_context ()

void
gtk_print_context_set_cairo_context (GtkPrintContext *context,
                                     cairo_t *cr,
                                     double dpi_x,
                                     double dpi_y);

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

context

a GtkPrintContext

 

cr

the cairo context

 

dpi_x

the horizontal resolution to use with cr

 

dpi_y

the vertical resolution to use with cr

 

Since: 2.10


gtk_print_context_get_page_setup ()

GtkPageSetup *
gtk_print_context_get_page_setup (GtkPrintContext *context);

Obtains the GtkPageSetup that determines the page dimensions of the GtkPrintContext.

Parameters

context

a GtkPrintContext

 

Returns

the page setup of context .

[transfer none]

Since: 2.10


gtk_print_context_get_width ()

gdouble
gtk_print_context_get_width (GtkPrintContext *context);

Obtains the width of the GtkPrintContext, in pixels.

Parameters

context

a GtkPrintContext

 

Returns

the width of context

Since: 2.10


gtk_print_context_get_height ()

gdouble
gtk_print_context_get_height (GtkPrintContext *context);

Obtains the height of the GtkPrintContext, in pixels.

Parameters

context

a GtkPrintContext

 

Returns

the height of context

Since: 2.10


gtk_print_context_get_dpi_x ()

gdouble
gtk_print_context_get_dpi_x (GtkPrintContext *context);

Obtains the horizontal resolution of the GtkPrintContext, in dots per inch.

Parameters

context

a GtkPrintContext

 

Returns

the horizontal resolution of context

Since: 2.10


gtk_print_context_get_dpi_y ()

gdouble
gtk_print_context_get_dpi_y (GtkPrintContext *context);

Obtains the vertical resolution of the GtkPrintContext, in dots per inch.

Parameters

context

a GtkPrintContext

 

Returns

the vertical resolution of context

Since: 2.10


gtk_print_context_get_pango_fontmap ()

PangoFontMap *
gtk_print_context_get_pango_fontmap (GtkPrintContext *context);

Returns a PangoFontMap that is suitable for use with the GtkPrintContext.

Parameters

context

a GtkPrintContext

 

Returns

the font map of context .

[transfer none]

Since: 2.10


gtk_print_context_create_pango_context ()

PangoContext *
gtk_print_context_create_pango_context
                               (GtkPrintContext *context);

Creates a new PangoContext that can be used with the GtkPrintContext.

Parameters

context

a GtkPrintContext

 

Returns

a new Pango context for context .

[transfer full]

Since: 2.10


gtk_print_context_create_pango_layout ()

PangoLayout *
gtk_print_context_create_pango_layout (GtkPrintContext *context);

Creates a new PangoLayout that is suitable for use with the GtkPrintContext.

Parameters

context

a GtkPrintContext

 

Returns

a new Pango layout for context .

[transfer full]

Since: 2.10


gtk_print_context_get_hard_margins ()

gboolean
gtk_print_context_get_hard_margins (GtkPrintContext *context,
                                    gdouble *top,
                                    gdouble *bottom,
                                    gdouble *left,
                                    gdouble *right);

Obtains the hardware printer margins of the GtkPrintContext, in units.

Parameters

context

a GtkPrintContext

 

top

top hardware printer margin.

[out]

bottom

bottom hardware printer margin.

[out]

left

left hardware printer margin.

[out]

right

right hardware printer margin.

[out]

Returns

TRUE if the hard margins were retrieved

Since: 2.20

Types and Values

GtkPrintContext

typedef struct _GtkPrintContext GtkPrintContext;