Gtk.PrintOperation¶
class — extends GObject.Object, PrintOperationPreview
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 PrintOperation.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 PrintOperation.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
PrintOperation.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
PrintOperationPreview.render_page,
PrintOperationPreview.end_preview and
PrintOperationPreview.is_selected
are useful when implementing a print preview.
Constructors¶
new¶
Creates a new GtkPrintOperation.
Methods¶
cancel¶
Cancels a running print operation.
This function may be called from a PrintOperation.begin-print,
PrintOperation.paginate or PrintOperation.draw-page
signal handler to stop the currently running print operation.
draw_page_finish¶
Signal that drawing of particular page is complete.
It is called after completion of page drawing (e.g. drawing
in another thread). If PrintOperation.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¶
Returns the default page setup.
get_embed_page_setup¶
Gets whether page setup selection combos are embedded
get_error¶
Call this when the result of a print operation is
PrintOperationResult.ERROR.
It can be called either after PrintOperation.run
returns, or in the PrintOperation.done signal
handler.
The returned GError will contain more details on what went wrong.
get_has_selection¶
Gets whether there is a selection.
get_n_pages_to_print¶
Returns the number of pages that will be printed.
Note that this value is set during print preparation phase
(PrintStatus.PREPARING), so this function should never be
called before the data generation phase (PrintStatus.GENERATING_DATA).
You can connect to the PrintOperation.status-changed
signal and call PrintOperation.get_n_pages_to_print when
print status is PrintStatus.GENERATING_DATA.
This is typically used to track the progress of print operation.
get_print_settings¶
Returns the current print settings.
Note that the return value is None until either
PrintOperation.set_print_settings or
PrintOperation.run have been called.
get_status¶
Returns the status of the print operation.
Also see PrintOperation.get_status_string.
get_status_string¶
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 PrintOperation.get_status to obtain
a status value that is suitable for programmatic use.
get_support_selection¶
Gets whether the application supports print of selection
is_finished¶
A convenience function to find out if the print operation is finished.
a print operation is finished if its status is either
PrintStatus.FINISHED or PrintStatus.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¶
def run(self, action: PrintOperationAction | int, parent: Window | 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
PrintOperation.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
PrintOperation.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 PrintOperation.run can only be called once on a
given GtkPrintOperation.
Parameters:
action— the action to startparent— Transient parent of the dialog
set_allow_async¶
Sets whether PrintOperation.run may return
before the print operation is completed.
Note that some platforms may not allow asynchronous operation.
Parameters:
allow_async—Trueto allow asynchronous operation
set_current_page¶
Sets the current page.
If this is called before PrintOperation.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¶
Sets the label for the tab holding custom widgets.
Parameters:
label— the label to use, orNoneto use the default label
set_default_page_setup¶
Makes default_page_setup the default page setup for op.
This page setup will be used by PrintOperation.run,
but it can be overridden on a per-page basis by connecting
to the PrintOperation.request-page-setup signal.
Parameters:
default_page_setup— aGtkPageSetup
set_defer_drawing¶
Sets up the GtkPrintOperation to wait for calling of
[methodGtk.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
PrintOperation.draw-page signal.
set_embed_page_setup¶
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—Trueto embed page setup selection in theGtkPrintUnixDialog
set_export_filename¶
def set_export_filename(self, filename: str | bytes | os.PathLike[str] | os.PathLike[bytes]) -> 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¶
Sets whether there is a selection to print.
Application has to set number of pages to which the selection
will draw by PrintOperation.set_n_pages in a handler
for the PrintOperation.begin-print signal.
Parameters:
has_selection—Trueindicates that a selection exists
set_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.
Parameters:
job_name— a string that identifies the print job
set_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 PrintOperation.begin-print
signal handler.
Note that the page numbers passed to the
PrintOperation.request-page-setup
and PrintOperation.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¶
Sets the print settings for op.
This is typically used to re-establish print settings
from a previous print operation, see PrintOperation.run.
Parameters:
print_settings—GtkPrintSettings
set_show_progress¶
If show_progress is True, the print operation will show
a progress dialog during the print operation.
Parameters:
show_progress—Trueto show a progress dialog
set_support_selection¶
Sets whether selection is supported by GtkPrintOperation.
Parameters:
support_selection—Trueto support selection
set_track_print_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.
Parameters:
track_status—Trueto track status after printing
set_unit¶
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¶
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—Trueto set up theGtkPrintContextfor the full page
Virtual methods¶
do_begin_print¶
Signal emitted after the user has finished changing print settings in the dialog, before the actual rendering starts.
do_custom_widget_apply¶
Signal emitted right before “begin-print” if you added a custom widget in the “create-custom-widget” handler.
do_done¶
Signal emitted when the print operation run has finished doing everything required for printing.
do_draw_page¶
Signal emitted for every page that is printed.
do_end_print¶
Signal emitted after all pages have been rendered.
do_paginate¶
Signal emitted after the “begin-print” signal, but before the actual rendering starts.
do_preview¶
Signal emitted when a preview is requested from the native dialog.
do_request_page_setup¶
Emitted once for every page that is printed, to give the application a chance to modify the page setup.
do_status_changed¶
Emitted at between the various phases of the print operation.
do_update_custom_widget¶
def do_update_custom_widget(self, widget: Widget, setup: PageSetup, settings: PrintSettings) -> None
Emitted after change of selected printer.
Properties¶
allow_async¶
Determines whether the print operation may run asynchronously or not.
Some systems don't support asynchronous printing, but those that do
will return PrintOperationResult.IN_PROGRESS as the status, and
emit the PrintOperation.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
PrintOperationAction.EXPORT support asynchronous operation.
current_page¶
The current page in the document.
If this is set before PrintOperation.run,
the user will be able to select to print only the current page.
Note that this only makes sense for pre-paginated documents.
custom_tab_label¶
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.
default_page_setup¶
The GtkPageSetup used by default.
This page setup will be used by PrintOperation.run,
but it can be overridden on a per-page basis by connecting
to the PrintOperation.request-page-setup signal.
embed_page_setup¶
If True, page size combo box and orientation combo box
are embedded into page setup page.
export_filename¶
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.
has_selection¶
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.
job_name¶
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.
n_pages¶
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 PrintOperation.begin-print
signal handler.
Note that the page numbers passed to the
PrintOperation.request-page-setup and
PrintOperation.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.
n_pages_to_print¶
The number of pages that will be printed.
Note that this value is set during print preparation phase
(PrintStatus.PREPARING), so this value should never be
get before the data generation phase (PrintStatus.GENERATING_DATA).
You can connect to the PrintOperation.status-changed signal
and call PrintOperation.get_n_pages_to_print when
print status is PrintStatus.GENERATING_DATA.
This is typically used to track the progress of print operation.
print_settings¶
The GtkPrintSettings used for initializing the dialog.
Setting this property is typically used to re-establish
print settings from a previous print operation, see
PrintOperation.run.
show_progress¶
Determines whether to show a progress dialog during the print operation.
status¶
The status of the print operation.
status_string¶
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 PrintOperation.status property for a status
value that is suitable for programmatic use.
support_selection¶
If True, the print operation will support print of selection.
This allows the print dialog to show a "Selection" button.
track_print_status¶
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.
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.
use_full_page¶
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¶
begin-print¶
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
PrintOperation.set_n_pages.
create-custom-widget¶
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 PrintOperation.custom-widget-apply
signal is emitted on the operation. Then you can read out any
information you need from the widgets.
custom-widget-apply¶
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.
done¶
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 PrintOperationResult.ERROR then you can call
PrintOperation.get_error for more information.
If you enabled print status tracking then
PrintOperation.is_finished may still return False
after the ::done signal was emitted.
draw-page¶
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
PrintContext.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 PrintOperation.set_use_full_page and
PrintOperation.set_unit before starting the print
operation to set up the transformation of the cairo context
according to your needs.
end-print¶
Emitted after all pages have been rendered.
A handler for this signal can clean up any resources that have
been allocated in the PrintOperation.begin-print handler.
paginate¶
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
PrintOperation.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.
preview¶
def on_preview(self, preview: PrintOperationPreview, context: PrintContext, parent: Window | 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
PrintContext.set_cairo_context.
The custom preview implementation can use
PrintOperationPreview.is_selected and
PrintOperationPreview.render_page to find pages which
are selected for print and render them. The preview must be
finished by calling PrintOperationPreview.end_preview
(typically in response to the user clicking a close button).
request-page-setup¶
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.
status-changed¶
Emitted at between the various phases of the print operation.
See PrintStatus for the phases that are being discriminated.
Use PrintOperation.get_status to find out the current
status.
update-custom-widget¶
def on_update_custom_widget(self, 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.