GtkPrintContext

## GtkPrintContext GtkPrintContext — Encapsulates context for drawing pages |

## Synopsis

    #include <gtk/gtk.h>

                        GtkPrintContext;
    cairo_t *           gtk_print_context_get_cairo_context (GtkPrintContext *context);
    void                gtk_print_context_set_cairo_context (GtkPrintContext *context,
                                                             cairo_t *cr,
                                                             double dpi_x,
                                                             double dpi_y);
    GtkPageSetup *      gtk_print_context_get_page_setup    (GtkPrintContext *context);
    gdouble             gtk_print_context_get_width         (GtkPrintContext *context);
    gdouble             gtk_print_context_get_height        (GtkPrintContext *context);
    gdouble             gtk_print_context_get_dpi_x         (GtkPrintContext *context);
    gdouble             gtk_print_context_get_dpi_y         (GtkPrintContext *context);
    PangoFontMap *      gtk_print_context_get_pango_fontmap (GtkPrintContext *context);
    PangoContext *      gtk_print_context_create_pango_context
                                                            (GtkPrintContext *context);
    PangoLayout *       gtk_print_context_create_pango_layout
                                                            (GtkPrintContext *context);
    gboolean            gtk_print_context_get_hard_margins  (GtkPrintContext *context,
                                                             gdouble *top,
                                                             gdouble *bottom,
                                                             gdouble *left,
                                                             gdouble *right);

## Object Hierarchy

      GObject
       +----GtkPrintContext

## 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.

Example 62. Using GtkPrintContext in a "draw-page" callback

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    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.

## Details

### GtkPrintContext

    typedef struct _GtkPrintContext GtkPrintContext;

### 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.

`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.

`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.

`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.

`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.

`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.

`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.

`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.

`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.

`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.

`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.

`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