GtkPrintOperation

typedef struct _GtkPrintOperation GtkPrintOperation;

enum GtkPrintStatus

typedef enum {
  GTK_PRINT_STATUS_INITIAL,
  GTK_PRINT_STATUS_PREPARING,
  GTK_PRINT_STATUS_GENERATING_DATA,
  GTK_PRINT_STATUS_SENDING_DATA,
  GTK_PRINT_STATUS_PENDING,
  GTK_PRINT_STATUS_PENDING_ISSUE,
  GTK_PRINT_STATUS_PRINTING,
  GTK_PRINT_STATUS_FINISHED,
  GTK_PRINT_STATUS_FINISHED_ABORTED
} GtkPrintStatus;

The status gives a rough indication of the completion of a running print operation.

enum GtkPrintOperationAction

typedef enum {
  GTK_PRINT_OPERATION_ACTION_PRINT_DIALOG,
  GTK_PRINT_OPERATION_ACTION_PRINT,
  GTK_PRINT_OPERATION_ACTION_PREVIEW,
  GTK_PRINT_OPERATION_ACTION_EXPORT
} GtkPrintOperationAction;

The action parameter to gtk_print_operation_run() determines what action the print operation should perform.

enum GtkPrintOperationResult

typedef enum {
  GTK_PRINT_OPERATION_RESULT_ERROR,
  GTK_PRINT_OPERATION_RESULT_APPLY,
  GTK_PRINT_OPERATION_RESULT_CANCEL,
  GTK_PRINT_OPERATION_RESULT_IN_PROGRESS
} GtkPrintOperationResult;

A value of this type is returned by gtk_print_operation_run().

enum GtkPrintError

typedef enum
{
  GTK_PRINT_ERROR_GENERAL,
  GTK_PRINT_ERROR_INTERNAL_ERROR,
  GTK_PRINT_ERROR_NOMEM,
  GTK_PRINT_ERROR_INVALID_FILE
} GtkPrintError;

Error codes that identify various errors that can occur while using the GTK+ printing support.

GTK_PRINT_ERROR

#define GTK_PRINT_ERROR gtk_print_error_quark ()

The GQuark used for GtkPrintError errors.

gtk_print_operation_new ()

GtkPrintOperation * gtk_print_operation_new             (void);

Creates a new GtkPrintOperation.

Since 2.10

gtk_print_operation_set_allow_async ()

void                gtk_print_operation_set_allow_async (GtkPrintOperation *op,
                                                         gboolean allow_async);

Sets whether the gtk_print_operation_run() may return before the print operation is completed. Note that some platforms may not allow asynchronous operation.

Since 2.10

gtk_print_operation_get_error ()

void                gtk_print_operation_get_error       (GtkPrintOperation *op,
                                                         GError **error);

Call this when the result of a print operation is GTK_PRINT_OPERATION_RESULT_ERROR, either as returned by gtk_print_operation_run(), or in the "done" signal handler. The returned GError will contain more details on what went wrong.

Since 2.10

gtk_print_operation_set_default_page_setup ()

void                gtk_print_operation_set_default_page_setup
                                                        (GtkPrintOperation *op,
                                                         GtkPageSetup *default_page_setup);

Makes default_page_setup the default page setup for op.

This page setup will be used by gtk_print_operation_run(), but it can be overridden on a per-page basis by connecting to the "request-page-setup" signal.

Since 2.10

gtk_print_operation_get_default_page_setup ()

GtkPageSetup *      gtk_print_operation_get_default_page_setup
                                                        (GtkPrintOperation *op);

Returns the default page setup, see gtk_print_operation_set_default_page_setup().

Since 2.10

gtk_print_operation_set_print_settings ()

void                gtk_print_operation_set_print_settings
                                                        (GtkPrintOperation *op,
                                                         GtkPrintSettings *print_settings);

Sets the print settings for op. This is typically used to re-establish print settings from a previous print operation, see gtk_print_operation_run().

Since 2.10

gtk_print_operation_get_print_settings ()

GtkPrintSettings *  gtk_print_operation_get_print_settings
                                                        (GtkPrintOperation *op);

Returns the current print settings.

Note that the return value is NULL until either gtk_print_operation_set_print_settings() or gtk_print_operation_run() have been called.

Since 2.10

gtk_print_operation_set_job_name ()

void                gtk_print_operation_set_job_name    (GtkPrintOperation *op,
                                                         const gchar *job_name);

Sets the name of the print job. The name is used to identify the job (e.g. in monitoring applications like eggcups).

If you don't set a job name, GTK+ picks a default one by numbering successive print jobs.

Since 2.10

gtk_print_operation_set_n_pages ()

void                gtk_print_operation_set_n_pages     (GtkPrintOperation *op,
                                                         gint n_pages);

Sets the number of pages in the document.

This must be set to a positive number before the rendering starts. It may be set in a "begin-print" signal hander.

Note that the page numbers passed to the "request-page-setup" and "draw-page" signals are 0-based, i.e. if the user chooses to print all pages, the last ::draw-page signal will be for page n_pages - 1.

Since 2.10

gtk_print_operation_get_n_pages_to_print ()

gint                gtk_print_operation_get_n_pages_to_print
                                                        (GtkPrintOperation *op);

Returns the number of pages that will be printed.

Note that this value is set during print preparation phase (GTK_PRINT_STATUS_PREPARING), so this function should never be called before the data generation phase (GTK_PRINT_STATUS_GENERATING_DATA). You can connect to the "status-changed" signal and call gtk_print_operation_get_n_pages_to_print() when print status is GTK_PRINT_STATUS_GENERATING_DATA. This is typically used to track the progress of print operation.

Since 2.18

gtk_print_operation_set_current_page ()

void                gtk_print_operation_set_current_page
                                                        (GtkPrintOperation *op,
                                                         gint current_page);

Sets the current page.

If this is called before gtk_print_operation_run(), the user will be able to select to print only the current page.

Note that this only makes sense for pre-paginated documents.

Since 2.10

gtk_print_operation_set_use_full_page ()

void                gtk_print_operation_set_use_full_page
                                                        (GtkPrintOperation *op,
                                                         gboolean full_page);

If full_page is TRUE, the transformation for the cairo context obtained from GtkPrintContext puts the origin at the top left corner of the page (which may not be the top left corner of the sheet, depending on page orientation and the number of pages per sheet). Otherwise, the origin is at the top left corner of the imageable area (i.e. inside the margins).

Since 2.10

gtk_print_operation_set_unit ()

void                gtk_print_operation_set_unit        (GtkPrintOperation *op,
                                                         GtkUnit unit);

Sets up the transformation for the cairo context obtained from GtkPrintContext in such a way that distances are measured in units of unit.

Since 2.10

gtk_print_operation_set_export_filename ()

void                gtk_print_operation_set_export_filename
                                                        (GtkPrintOperation *op,
                                                         const gchar *filename);

Sets up the GtkPrintOperation to generate a file instead of showing the print dialog. The indended use of this function is for implementing "Export to PDF" actions. Currently, PDF is the only supported format.

"Print to PDF" support is independent of this and is done by letting the user pick the "Print to PDF" item from the list of printers in the print dialog.

Since 2.10

gtk_print_operation_set_show_progress ()

void                gtk_print_operation_set_show_progress
                                                        (GtkPrintOperation *op,
                                                         gboolean show_progress);

If show_progress is TRUE, the print operation will show a progress dialog during the print operation.

Since 2.10

gtk_print_operation_set_track_print_status ()

void                gtk_print_operation_set_track_print_status
                                                        (GtkPrintOperation *op,
                                                         gboolean track_status);

If track_status is TRUE, the print operation will try to continue report on the status of the print job in the printer queues and printer. This can allow your application to show things like "out of paper" issues, and when the print job actually reaches the printer.

This function is often implemented using some form of polling, so it should not be enabled unless needed.

Since 2.10

gtk_print_operation_set_custom_tab_label ()

void                gtk_print_operation_set_custom_tab_label
                                                        (GtkPrintOperation *op,
                                                         const gchar *label);

Sets the label for the tab holding custom widgets.

Since 2.10

gtk_print_operation_run ()

GtkPrintOperationResult  gtk_print_operation_run        (GtkPrintOperation *op,
                                                         GtkPrintOperationAction action,
                                                         GtkWindow *parent,
                                                         GError **error);

Runs the print operation, by first letting the user modify print settings in the print dialog, and then print the document.

Normally that this function does not return until the rendering of all pages is complete. You can connect to the "status-changed" signal on op to obtain some information about the progress of the print operation. Furthermore, it may use a recursive mainloop to show the print dialog.

If you call gtk_print_operation_set_allow_async() or set the "allow-async" property the operation will run asynchronously if this is supported on the platform. The "done" signal will be emitted with the result of the operation when the it is done (i.e. when the dialog is canceled, or when the print succeeds or fails).

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

if (settings != NULL)
  gtk_print_operation_set_print_settings (print, settings);
  
if (page_setup != NULL)
  gtk_print_operation_set_default_page_setup (print, page_setup);
  
g_signal_connect (print, "begin-print", 
                  G_CALLBACK (begin_print), &data);
g_signal_connect (print, "draw-page", 
                  G_CALLBACK (draw_page), &data);
 
res = gtk_print_operation_run (print, 
                               GTK_PRINT_OPERATION_ACTION_PRINT_DIALOG, 
                               parent, 
                               &error);
 
if (res == GTK_PRINT_OPERATION_RESULT_ERROR)
 {
   error_dialog = gtk_message_dialog_new (GTK_WINDOW (parent),
                                 GTK_DIALOG_DESTROY_WITH_PARENT,
                         GTK_MESSAGE_ERROR,
                         GTK_BUTTONS_CLOSE,
                         "Error printing file:\n%s",
                         error->message);
   g_signal_connect (error_dialog, "response", 
                     G_CALLBACK (gtk_widget_destroy), NULL);
   gtk_widget_show (error_dialog);
   g_error_free (error);
 }
else if (res == GTK_PRINT_OPERATION_RESULT_APPLY)
 {
   if (settings != NULL)
g_object_unref (settings);
   settings = g_object_ref (gtk_print_operation_get_print_settings (print));
 }

Note that gtk_print_operation_run() can only be called once on a given GtkPrintOperation.

Since 2.10

gtk_print_operation_cancel ()

void                gtk_print_operation_cancel          (GtkPrintOperation *op);

Cancels a running print operation. This function may be called from a "begin-print", "paginate" or "draw-page" signal handler to stop the currently running print operation.

Since 2.10

gtk_print_operation_draw_page_finish ()

void                gtk_print_operation_draw_page_finish
                                                        (GtkPrintOperation *op);

Signalize that drawing of particular page is complete.

It is called after completion of page drawing (e.g. drawing in another thread). If gtk_print_operation_set_defer_drawing() was called before, then this function has to be called by application. In another case it is called by the library itself.

Since 2.16

gtk_print_operation_set_defer_drawing ()

void                gtk_print_operation_set_defer_drawing
                                                        (GtkPrintOperation *op);

Sets up the GtkPrintOperation to wait for calling of gtk_print_operation_draw_page_finish() from application. It can be used for drawing page in another thread.

This function must be called in the callback of "draw-page" signal.

Since 2.16

gtk_print_operation_get_status ()

GtkPrintStatus      gtk_print_operation_get_status      (GtkPrintOperation *op);

Returns the status of the print operation. Also see gtk_print_operation_get_status_string().

Since 2.10

gtk_print_operation_get_status_string ()

const gchar *       gtk_print_operation_get_status_string
                                                        (GtkPrintOperation *op);

Returns a string representation of the status of the print operation. The string is translated and suitable for displaying the print status e.g. in a GtkStatusbar.

Use gtk_print_operation_get_status() to obtain a status value that is suitable for programmatic use.

Since 2.10

gtk_print_operation_is_finished ()

gboolean            gtk_print_operation_is_finished     (GtkPrintOperation *op);

A convenience function to find out if the print operation is finished, either successfully (GTK_PRINT_STATUS_FINISHED) or unsuccessfully (GTK_PRINT_STATUS_FINISHED_ABORTED).

Note: when you enable print status tracking the print operation can be in a non-finished state even after done has been called, as the operation status then tracks the print job status on the printer.

Since 2.10

gtk_print_operation_set_support_selection ()

void                gtk_print_operation_set_support_selection
                                                        (GtkPrintOperation *op,
                                                         gboolean support_selection);

Sets whether selection is supported by GtkPrintOperation.

Since 2.18

gtk_print_operation_get_support_selection ()

gboolean            gtk_print_operation_get_support_selection
                                                        (GtkPrintOperation *op);

Gets the value of "support-selection" property.

Since 2.18

gtk_print_operation_set_has_selection ()

void                gtk_print_operation_set_has_selection
                                                        (GtkPrintOperation *op,
                                                         gboolean has_selection);

Sets whether there is a selection to print.

Application has to set number of pages to which the selection will draw by gtk_print_operation_set_n_pages() in a callback of "begin-print".

Since 2.18

gtk_print_operation_get_has_selection ()

gboolean            gtk_print_operation_get_has_selection
                                                        (GtkPrintOperation *op);

Gets the value of "has-selection" property.

Since 2.18

gtk_print_operation_set_embed_page_setup ()

void                gtk_print_operation_set_embed_page_setup
                                                        (GtkPrintOperation *op,
                                                         gboolean embed);

Embed page size combo box and orientation combo box into page setup page. Selected page setup is stored as default page setup in GtkPrintOperation.

Since 2.18

gtk_print_operation_get_embed_page_setup ()

gboolean            gtk_print_operation_get_embed_page_setup
                                                        (GtkPrintOperation *op);

Gets the value of "embed-page-setup" property.

Since 2.18

gtk_print_run_page_setup_dialog ()

GtkPageSetup *      gtk_print_run_page_setup_dialog     (GtkWindow *parent,
                                                         GtkPageSetup *page_setup,
                                                         GtkPrintSettings *settings);

Runs a page setup dialog, letting the user modify the values from page_setup. If the user cancels the dialog, the returned GtkPageSetup is identical to the passed in page_setup, otherwise it contains the modifications done in the dialog.

Note that this function may use a recursive mainloop to show the page setup dialog. See gtk_print_run_page_setup_dialog_async() if this is a problem.

Since 2.10

GtkPageSetupDoneFunc ()

void                (*GtkPageSetupDoneFunc)             (GtkPageSetup *page_setup,
                                                         gpointer data);

The type of function that is passed to gtk_print_run_page_setup_dialog_async(). This function will be called when the page setup dialog is dismissed, and also serves as destroy notify for data.

gtk_print_run_page_setup_dialog_async ()

void                gtk_print_run_page_setup_dialog_async
                                                        (GtkWindow *parent,
                                                         GtkPageSetup *page_setup,
                                                         GtkPrintSettings *settings,
                                                         GtkPageSetupDoneFunc done_cb,
                                                         gpointer data);

Runs a page setup dialog, letting the user modify the values from page_setup.

In contrast to gtk_print_run_page_setup_dialog(), this function returns after showing the page setup dialog on platforms that support this, and calls done_cb from a signal handler for the ::response signal of the dialog.

Since 2.10

GtkPrintOperationPreview

typedef struct _GtkPrintOperationPreview GtkPrintOperationPreview;

gtk_print_operation_preview_end_preview ()

void                gtk_print_operation_preview_end_preview
                                                        (GtkPrintOperationPreview *preview);

Ends a preview.

This function must be called to finish a custom print preview.

Since 2.10

gtk_print_operation_preview_is_selected ()

gboolean            gtk_print_operation_preview_is_selected
                                                        (GtkPrintOperationPreview *preview,
                                                         gint page_nr);

Returns whether the given page is included in the set of pages that have been selected for printing.

Since 2.10

gtk_print_operation_preview_render_page ()

void                gtk_print_operation_preview_render_page
                                                        (GtkPrintOperationPreview *preview,
                                                         gint page_nr);

Renders a page to the preview, using the print context that was passed to the "preview" handler together with preview.

A custom iprint preview should use this function in its ::expose handler to render the currently selected page.

Note that this function requires a suitable cairo context to be associated with the print context.

Since 2.10

The "allow-async" property

  "allow-async"              gboolean              : Read / Write

Determines whether the print operation may run asynchronously or not.

Some systems don't support asynchronous printing, but those that do will return GTK_PRINT_OPERATION_RESULT_IN_PROGRESS as the status, and emit the "done" signal when the operation is actually done.

The Windows port does not support asynchronous operation at all (this is unlikely to change). On other platforms, all actions except for GTK_PRINT_OPERATION_ACTION_EXPORT support asynchronous operation.

Default value: FALSE

Since 2.10

The "current-page" property

  "current-page"             gint                  : Read / Write

The current page in the document.

If this is set before gtk_print_operation_run(), the user will be able to select to print only the current page.

Note that this only makes sense for pre-paginated documents.

Allowed values: >= G_MAXULONG

Default value: -1

Since 2.10

The "custom-tab-label" property

  "custom-tab-label"         gchar*                : Read / Write

Used as the label of the tab containing custom widgets. Note that this property may be ignored on some platforms.

If this is NULL, GTK+ uses a default label.

Default value: NULL

Since 2.10

The "default-page-setup" property

  "default-page-setup"       GtkPageSetup*         : Read / Write

The GtkPageSetup used by default.

This page setup will be used by gtk_print_operation_run(), but it can be overridden on a per-page basis by connecting to the "request-page-setup" signal.

Since 2.10

The "embed-page-setup" property

  "embed-page-setup"         gboolean              : Read / Write

If TRUE, page size combo box and orientation combo box are embedded into page setup page.

Default value: FALSE

Since 2.18

The "export-filename" property

  "export-filename"          gchar*                : Read / Write

The name of a file to generate instead of showing the print dialog. Currently, PDF is the only supported format.

The intended use of this property is for implementing "Export to PDF" actions.

"Print to PDF" support is independent of this and is done by letting the user pick the "Print to PDF" item from the list of printers in the print dialog.

Default value: NULL

Since 2.10

The "has-selection" property

  "has-selection"            gboolean              : Read / Write

Determines whether there is a selection in your application. This can allow your application to print the selection. This is typically used to make a "Selection" button sensitive.

Default value: FALSE

Since 2.18

The "job-name" property

  "job-name"                 gchar*                : Read / Write

A string used to identify the job (e.g. in monitoring applications like eggcups).

If you don't set a job name, GTK+ picks a default one by numbering successive print jobs.

Default value: ""

Since 2.10

The "n-pages" property

  "n-pages"                  gint                  : Read / Write

The number of pages in the document.

This must be set to a positive number before the rendering starts. It may be set in a "begin-print" signal hander.

Note that the page numbers passed to the "request-page-setup" and "draw-page" signals are 0-based, i.e. if the user chooses to print all pages, the last ::draw-page signal will be for page n_pages - 1.

Allowed values: >= G_MAXULONG

Default value: -1

Since 2.10

The "n-pages-to-print" property

  "n-pages-to-print"         gint                  : Read

The number of pages that will be printed.

Note that this value is set during print preparation phase (GTK_PRINT_STATUS_PREPARING), so this value should never be get before the data generation phase (GTK_PRINT_STATUS_GENERATING_DATA). You can connect to the "status-changed" signal and call gtk_print_operation_get_n_pages_to_print() when print status is GTK_PRINT_STATUS_GENERATING_DATA. This is typically used to track the progress of print operation.

Allowed values: >= G_MAXULONG

Default value: -1

Since 2.18

The "print-settings" property

  "print-settings"           GtkPrintSettings*     : Read / Write

The GtkPrintSettings used for initializing the dialog.

Setting this property is typically used to re-establish print settings from a previous print operation, see gtk_print_operation_run().

Since 2.10

The "show-progress" property

  "show-progress"            gboolean              : Read / Write

Determines whether to show a progress dialog during the print operation.

Default value: FALSE

Since 2.10

The "status" property

  "status"                   GtkPrintStatus        : Read

The status of the print operation.

Default value: GTK_PRINT_STATUS_INITIAL

Since 2.10

The "status-string" property

  "status-string"            gchar*                : Read

A string representation of the status of the print operation. The string is translated and suitable for displaying the print status e.g. in a GtkStatusbar.

See the "status" property for a status value that is suitable for programmatic use.

Default value: ""

Since 2.10

The "support-selection" property

  "support-selection"        gboolean              : Read / Write

If TRUE, the print operation will support print of selection. This allows the print dialog to show a "Selection" button.

Default value: FALSE

Since 2.18

The "track-print-status" property

  "track-print-status"       gboolean              : Read / Write

If TRUE, the print operation will try to continue report on the status of the print job in the printer queues and printer. This can allow your application to show things like "out of paper" issues, and when the print job actually reaches the printer. However, this is often implemented using polling, and should not be enabled unless needed.

Default value: FALSE

Since 2.10

The "unit" property

  "unit"                     GtkUnit               : Read / Write

The transformation for the cairo context obtained from GtkPrintContext is set up in such a way that distances are measured in units of unit.

Default value: GTK_UNIT_PIXEL

Since 2.10

The "use-full-page" property

  "use-full-page"            gboolean              : Read / Write

If TRUE, the transformation for the cairo context obtained from GtkPrintContext puts the origin at the top left corner of the page (which may not be the top left corner of the sheet, depending on page orientation and the number of pages per sheet). Otherwise, the origin is at the top left corner of the imageable area (i.e. inside the margins).

Default value: FALSE

Since 2.10

The "begin-print" signal

void                user_function                      (GtkPrintOperation *operation,
                                                        GtkPrintContext   *context,
                                                        gpointer           user_data)      : Run Last

Emitted after the user has finished changing print settings in the dialog, before the actual rendering starts.

A typical use for ::begin-print is to use the parameters from the GtkPrintContext and paginate the document accordingly, and then set the number of pages with gtk_print_operation_set_n_pages().

Since 2.10

The "create-custom-widget" signal

GObject*            user_function                      (GtkPrintOperation *operation,
                                                        gpointer           user_data)      : Run Last

Emitted when displaying the print dialog. If you return a widget in a handler for this signal it will be added to a custom tab in the print dialog. You typically return a container widget with multiple widgets in it.

The print dialog owns the returned widget, and its lifetime is not controlled by the application. However, the widget is guaranteed to stay around until the "custom-widget-apply" signal is emitted on the operation. Then you can read out any information you need from the widgets.

Since 2.10

The "custom-widget-apply" signal

void                user_function                      (GtkPrintOperation *operation,
                                                        GtkWidget         *widget,
                                                        gpointer           user_data)      : Run Last

Emitted right before "begin-print" if you added a custom widget in the "create-custom-widget" handler. When you get this signal you should read the information from the custom widgets, as the widgets are not guaraneed to be around at a later time.

Since 2.10

The "done" signal

void                user_function                      (GtkPrintOperation      *operation,
                                                        GtkPrintOperationResult result,
                                                        gpointer                user_data)      : Run Last

Emitted when the print operation run has finished doing everything required for printing.

result gives you information about what happened during the run. If result is GTK_PRINT_OPERATION_RESULT_ERROR then you can call gtk_print_operation_get_error() for more information.

If you enabled print status tracking then gtk_print_operation_is_finished() may still return FALSE after "done" was emitted.

Since 2.10

The "draw-page" signal

void                user_function                      (GtkPrintOperation *operation,
                                                        GtkPrintContext   *context,
                                                        gint               page_nr,
                                                        gpointer           user_data)      : Run Last

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_print_context_get_cairo_context().

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

static void
draw_page (GtkPrintOperation *operation,
           GtkPrintContext   *context,
           gint               page_nr,
           gpointer           user_data)
{
  cairo_t *cr;
  PangoLayout *layout;
  gdouble width, text_height;
  gint 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 = (gdouble)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_print_operation_set_use_full_page() and gtk_print_operation_set_unit() before starting the print operation to set up the transformation of the cairo context according to your needs.

Since 2.10

The "end-print" signal

void                user_function                      (GtkPrintOperation *operation,
                                                        GtkPrintContext   *context,
                                                        gpointer           user_data)      : Run Last

Emitted after all pages have been rendered. A handler for this signal can clean up any resources that have been allocated in the "begin-print" handler.

Since 2.10

The "paginate" signal

gboolean            user_function                      (GtkPrintOperation *operation,
                                                        GtkPrintContext   *context,
                                                        gpointer           user_data)      : Run Last

Emitted after the "begin-print" signal, but before the actual rendering starts. It keeps getting emitted until a connected signal handler returns TRUE.

The ::paginate signal is intended to be used for paginating a document in small chunks, to avoid blocking the user interface for a long time. The signal handler should update the number of pages using gtk_print_operation_set_n_pages(), and return TRUE if the document has been completely paginated.

If you don't need to do pagination in chunks, you can simply do it all in the ::begin-print handler, and set the number of pages from there.

Since 2.10

The "preview" signal

gboolean            user_function                      (GtkPrintOperation        *operation,
                                                        GtkPrintOperationPreview *preview,
                                                        GtkPrintContext          *context,
                                                        GtkWindow                *parent,
                                                        gpointer                  user_data)      : Run Last

Gets emitted when a preview is requested from the native dialog.

The default handler for this signal uses an external viewer application to preview.

To implement a custom print preview, an application must return TRUE from its handler for this signal. In order to use the provided context for the preview implementation, it must be given a suitable cairo context with gtk_print_context_set_cairo_context().

The custom preview implementation can use gtk_print_operation_preview_is_selected() and gtk_print_operation_preview_render_page() to find pages which are selected for print and render them. The preview must be finished by calling gtk_print_operation_preview_end_preview() (typically in response to the user clicking a close button).

Since 2.10

The "request-page-setup" signal

void                user_function                      (GtkPrintOperation *operation,
                                                        GtkPrintContext   *context,
                                                        gint               page_nr,
                                                        GtkPageSetup      *setup,
                                                        gpointer           user_data)      : Run Last

Emitted once for every page that is printed, to give the application a chance to modify the page setup. Any changes done to setup will be in force only for printing this page.

Since 2.10

The "status-changed" signal

void                user_function                      (GtkPrintOperation *operation,
                                                        gpointer           user_data)      : Run Last

Emitted at between the various phases of the print operation. See GtkPrintStatus for the phases that are being discriminated. Use gtk_print_operation_get_status() to find out the current status.

Since 2.10

The "update-custom-widget" signal

void                user_function                      (GtkPrintOperation *operation,
                                                        GtkWidget         *widget,
                                                        GtkPageSetup      *setup,
                                                        GtkPrintSettings  *settings,
                                                        gpointer           user_data)      : Run Last

Emitted after change of selected printer. The actual page setup and print settings are passed to the custom widget, which can actualize itself according to this change.

Since 2.18

The "got-page-size" signal

void                user_function                      (GtkPrintOperationPreview *preview,
                                                        GtkPrintContext          *context,
                                                        GtkPageSetup             *page_setup,
                                                        gpointer                  user_data)       : Run Last

The ::got-page-size signal is emitted once for each page that gets rendered to the preview.

A handler for this signal should update the context according to page_setup and set up a suitable cairo context, using gtk_print_context_set_cairo_context().

The "ready" signal

void                user_function                      (GtkPrintOperationPreview *preview,
                                                        GtkPrintContext          *context,
                                                        gpointer                  user_data)      : Run Last

The ::ready signal gets emitted once per preview operation, before the first page is rendered.

A handler for this signal can be used for setup tasks.