PrintOperation

class PrintOperation(**properties: Any)

Superclasses: Object

Implemented Interfaces: PrintOperationPreview

GtkPrintOperation is the high-level, portable printing API.

It looks a bit different than other GTK dialogs such as the GtkFileChooser, since some platforms don’t expose enough infrastructure to implement a good print dialog. On such platforms, GtkPrintOperation uses the native print dialog. On platforms which do not provide a native print dialog, GTK uses its own, see PrintUnixDialog.

The typical way to use the high-level printing API is to create a GtkPrintOperation object with new when the user selects to print. Then you set some properties on it, e.g. the page size, any PrintSettings from previous print operations, the number of pages, the current page, etc.

Then you start the print operation by calling run. It will then show a dialog, let the user select a printer and options. When the user finished the dialog, various signals will be emitted on the GtkPrintOperation, the main one being draw_page, which you are supposed to handle and render the page on the provided PrintContext using Cairo.

The high-level printing API

static GtkPrintSettings *settings = NULL;

static void
do_print (void)
{
  GtkPrintOperation *print;
  GtkPrintOperationResult res;

  print = gtk_print_operation_new ();

  if (settings != NULL)
    gtk_print_operation_set_print_settings (print, settings);

  g_signal_connect (print, "begin_print", G_CALLBACK (begin_print), NULL);
  g_signal_connect (print, "draw_page", G_CALLBACK (draw_page), NULL);

  res = gtk_print_operation_run (print, GTK_PRINT_OPERATION_ACTION_PRINT_DIALOG,
                                 GTK_WINDOW (main_window), NULL);

  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));
    }

  g_object_unref (print);
}

By default GtkPrintOperation uses an external application to do print preview. To implement a custom print preview, an application must connect to the preview signal. The functions render_page, end_preview and is_selected are useful when implementing a print preview.

Constructors

class PrintOperation

classmethod new() → PrintOperation: Creates a new GtkPrintOperation.

Methods

class PrintOperation

cancel() → None

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.

draw_page_finish() → None

Signal that drawing of particular page is complete.

It is called after completion of page drawing (e.g. drawing in another thread). If set_defer_drawing was called before, then this function has to be called by application. Otherwise it is called by GTK itself.

get_default_page_setup() → PageSetup: Returns the default page setup.

get_embed_page_setup() → bool: Gets whether page setup selection combos are embedded

get_error() → None

Call this when the result of a print operation is ERROR.

It can be called either after run returns, or in the done signal handler.

The returned GError will contain more details on what went wrong.

get_has_selection() → bool: Gets whether there is a selection.

get_n_pages_to_print() → int

Returns the number of pages that will be printed.

Note that this value is set during print preparation phase (PREPARING), so this function should never be called before the data generation phase (GENERATING_DATA). You can connect to the status_changed signal and call get_n_pages_to_print() when print status is GENERATING_DATA.

This is typically used to track the progress of print operation.

get_print_settings() → PrintSettings | None

Returns the current print settings.

Note that the return value is None until either set_print_settings or run have been called.

get_status() → PrintStatus

Returns the status of the print operation.

Also see get_status_string.

get_status_string() → str

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 get_status to obtain a status value that is suitable for programmatic use.

get_support_selection() → bool: Gets whether the application supports print of selection

is_finished() → bool

A convenience function to find out if the print operation is finished.

a print operation is finished if its status is either FINISHED or 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.

run(action: PrintOperationAction, parent: Window | None = None) → PrintOperationResult

Runs the print operation.

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 set the [Gtk.PrintOperation: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).

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_window_destroy), NULL);
   gtk_window_present (GTK_WINDOW (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 run() can only be called once on a given GtkPrintOperation.

Parameters:

action – the action to start
parent – Transient parent of the dialog

set_allow_async(allow_async: bool) → None

Sets whether run() may return before the print operation is completed.

Note that some platforms may not allow asynchronous operation.

Parameters:: allow_async – True to allow asynchronous operation

set_current_page(current_page: int) → None

Sets the current page.

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

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

Parameters:: current_page – the current page, 0-based

set_custom_tab_label(label: str | None = None) → None

Sets the label for the tab holding custom widgets.

Parameters:: label – the label to use, or None to use the default label

set_default_page_setup(default_page_setup: PageSetup | None = None) → None

Makes default_page_setup the default page setup for op.

This page setup will be used by run, but it can be overridden on a per-page basis by connecting to the request_page_setup signal.

Parameters:: default_page_setup – a GtkPageSetup

set_defer_drawing() → None

Sets up the GtkPrintOperation to wait for calling of [method``Gtk``.PrintOperation.draw_page_finish from application.

This can be used for drawing page in another thread.

This function must be called in the callback of the draw_page signal.

set_embed_page_setup(embed: bool) → None

Embed page size combo box and orientation combo box into page setup page.

Selected page setup is stored as default page setup in GtkPrintOperation.

Parameters:: embed – True to embed page setup selection in the GtkPrintUnixDialog

set_export_filename(filename: str) → None

Sets up the GtkPrintOperation to generate a file instead of showing the print dialog.

The intended 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.

Parameters:: filename – the filename for the exported file

set_has_selection(has_selection: bool) → None

Sets whether there is a selection to print.

Application has to set number of pages to which the selection will draw by set_n_pages in a handler for the begin_print signal.

Parameters:: has_selection – True indicates that a selection exists

set_job_name(job_name: str) → None

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.

Parameters:: job_name – a string that identifies the print job

set_n_pages(n_pages: int) → None

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 handler.

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.

Parameters:: n_pages – the number of pages

set_print_settings(print_settings: PrintSettings | None = None) → None

Sets the print settings for op.

This is typically used to re-establish print settings from a previous print operation, see run.

Parameters:: print_settings – GtkPrintSettings

set_show_progress(show_progress: bool) → None

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

Parameters:: show_progress – True to show a progress dialog

set_support_selection(support_selection: bool) → None

Sets whether selection is supported by GtkPrintOperation.

Parameters:: support_selection – True to support selection

set_track_print_status(track_status: bool) → None

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.

Parameters:: track_status – True to track status after printing

set_unit(unit: Unit) → None

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

Parameters:: unit – the unit to use

set_use_full_page(full_page: bool) → None

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.

This 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).

Parameters:: full_page – True to set up the GtkPrintContext for the full page

Properties

class PrintOperation

props.allow_async: bool

Determines whether the print operation may run asynchronously or not.

Some systems don’t support asynchronous printing, but those that do will return 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 EXPORT support asynchronous operation.

props.current_page: int

The current page in the document.

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

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

props.custom_tab_label: str

Used as the label of the tab containing custom widgets.

Note that this property may be ignored on some platforms.

If this is None, GTK uses a default label.

props.default_page_setup: PageSetup

The GtkPageSetup used by default.

This page setup will be used by run, but it can be overridden on a per-page basis by connecting to the request_page_setup signal.

props.embed_page_setup: bool: If True, page size combo box and orientation combo box are embedded into page setup page.

props.export_filename: str

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.

props.has_selection: bool

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.

props.job_name: str

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.

props.n_pages: int

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 handler.

props.n_pages_to_print: int

The number of pages that will be printed.

Note that this value is set during print preparation phase (PREPARING), so this value should never be get before the data generation phase (GENERATING_DATA). You can connect to the status_changed signal and call get_n_pages_to_print when print status is GENERATING_DATA.

This is typically used to track the progress of print operation.

props.print_settings: PrintSettings

The GtkPrintSettings used for initializing the dialog.

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

props.show_progress: bool: Determines whether to show a progress dialog during the print operation.

props.status: PrintStatus: The status of the print operation.

props.status_string: str

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.

props.support_selection: bool

If True, the print operation will support print of selection.

This allows the print dialog to show a “Selection” button.

props.track_print_status: bool

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.

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

props.use_full_page: bool

If True, the transformation for the cairo context obtained from GtkPrintContext puts the origin at the top left corner of the page.

This 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).

Signals

class PrintOperation.signals

begin_print(context: PrintContext) → None

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 PrintContext and paginate the document accordingly, and then set the number of pages with set_n_pages.

Parameters:: context – the GtkPrintContext for the current operation

create_custom_widget() → Object | None

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.

custom_widget_apply(widget: Widget) → None

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 guaranteed to be around at a later time.

Parameters:: widget – the custom widget added in ::create-custom-widget

done(result: PrintOperationResult) → None

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 ERROR then you can call get_error for more information.

If you enabled print status tracking then is_finished may still return False after the ::done signal was emitted.

Parameters:: result – the result of the print operation

draw_page(context: PrintContext, page_nr: int) → None

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 get_cairo_context.

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

Parameters:

context – the GtkPrintContext for the current operation
page_nr – the number of the currently printed page (0-based)

end_print(context: PrintContext) → None

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.

Parameters:: context – the GtkPrintContext for the current operation

paginate(context: PrintContext) → bool

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 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.

Parameters:: context – the GtkPrintContext for the current operation

preview(preview: PrintOperationPreview, context: PrintContext, parent: Window | None = None) → bool

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 set_cairo_context.

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

Parameters:

preview – the GtkPrintOperationPreview for the current operation
context – the GtkPrintContext that will be used
parent – the GtkWindow to use as window parent

request_page_setup(context: PrintContext, page_nr: int, setup: PageSetup) → None

Emitted once for every page that is printed.

This gives the application a chance to modify the page setup. Any changes done to setup will be in force only for printing this page.

Parameters:

context – the GtkPrintContext for the current operation
page_nr – the number of the currently printed page (0-based)
setup – the GtkPageSetup

status_changed() → None

Emitted at between the various phases of the print operation.

See PrintStatus for the phases that are being discriminated. Use get_status to find out the current status.

update_custom_widget(widget: Widget, setup: PageSetup, settings: PrintSettings) → None

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.

Parameters:

widget – the custom widget added in ::create-custom-widget
setup – actual page setup
settings – actual print settings

Virtual Methods

class PrintOperation

do_begin_print(context: PrintContext) → None

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

Parameters:: context

do_custom_widget_apply(widget: Widget) → None

Signal emitted right before “begin-print” if you added a custom widget in the “create-custom-widget” handler.

Parameters:: widget

do_done(result: PrintOperationResult) → None

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

Parameters:: result

do_draw_page(context: PrintContext, page_nr: int) → None

Signal emitted for every page that is printed.

Parameters:

context
page_nr

do_end_print(context: PrintContext) → None

Signal emitted after all pages have been rendered.

Parameters:: context

do_paginate(context: PrintContext) → bool

Signal emitted after the “begin-print” signal, but before the actual rendering starts.

Parameters:: context

do_preview(preview: PrintOperationPreview, context: PrintContext, parent: Window) → bool

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

Parameters:

preview
context
parent

do_request_page_setup(context: PrintContext, page_nr: int, setup: PageSetup) → None

Emitted once for every page that is printed, to give the application a chance to modify the page setup.

Parameters:

context
page_nr
setup

do_status_changed() → None: Emitted at between the various phases of the print operation.

do_update_custom_widget(widget: Widget, setup: PageSetup, settings: PrintSettings) → None

Emitted after change of selected printer.

Parameters:

widget
setup
settings

Fields

class PrintOperation

parent_instance

priv