<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Example</title>
<link rel="stylesheet" type="text/css" href="style.css">
<meta name="generator" content="DocBook XSL Stylesheets V1.79.1">
<link rel="home" href="index.html" title="Programming with gtkmm 3">
<link rel="up" href="chapter-printing.html" title="Chapter 20. Printing">
<link rel="prev" href="sec-printing-preview.html" title="Preview">
<link rel="next" href="chapter-recent-documents.html" title="Chapter 21. Recently Used Documents">
</head>
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
<div class="navheader">
<table width="100%" summary="Navigation header">
<tr><th colspan="3" align="center">Example</th></tr>
<tr>
<td width="20%" align="left">
<a accesskey="p" href="sec-printing-preview.html"><img src="icons/prev.png" alt="Prev"></a> </td>
<th width="60%" align="center">Chapter 20. Printing</th>
<td width="20%" align="right"> <a accesskey="n" href="chapter-recent-documents.html"><img src="icons/next.png" alt="Next"></a>
</td>
</tr>
</table>
<hr>
</div>
<div class="sect1">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="sec-printing-example"></a>Example</h2></div></div></div>
<div class="sect2">
<div class="titlepage"><div><div><h3 class="title">
<a name="sec-printing-example-simple"></a>Simple</h3></div></div></div>
<p>
The following example demonstrates how to print some input from a user
interface. It shows how to implement <code class="literal">on_begin_print</code>
and <code class="literal">on_draw_page</code>, as well as how to track print status
and update the print settings.
</p>
<div class="figure">
<a name="figure-printing-simple"></a><p class="title"><b>Figure 20.1. Printing - Simple</b></p>
<div class="figure-contents"><div class="screenshot"><div><img src="figures/printing.png" alt="Printing - Simple"></div></div></div>
</div>
<br class="figure-break"><p><a class="ulink" href="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/printing/simple/?h=gtkmm-3-24" target="_top">Source Code</a></p>
<p>File: <code class="filename">examplewindow.h</code> (For use with gtkmm 3, not gtkmm 2)
</p>
<pre class="programlisting">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H
// This file is part of the printing/simple and printing/advanced examples
#include <gtkmm.h>
class PrintFormOperation;
class ExampleWindow : public Gtk::Window
{
public:
ExampleWindow(const Glib::RefPtr<Gtk::Application>& app);
virtual ~ExampleWindow();
protected:
void build_main_menu(const Glib::RefPtr<Gtk::Application>& app);
void print_or_preview(Gtk::PrintOperationAction print_action);
//PrintOperation signal handlers.
//We handle these so can get necessary information to update the UI or print settings.
//Our derived PrintOperation class also overrides some default signal handlers.
void on_printoperation_status_changed();
void on_printoperation_done(Gtk::PrintOperationResult result);
//Action signal handlers:
void on_menu_file_new();
void on_menu_file_page_setup();
void on_menu_file_print_preview();
void on_menu_file_print();
void on_menu_file_quit();
//Printing-related objects:
Glib::RefPtr<Gtk::PageSetup> m_refPageSetup;
Glib::RefPtr<Gtk::PrintSettings> m_refSettings;
Glib::RefPtr<PrintFormOperation> m_refPrintFormOperation;
//Child widgets:
Gtk::Box m_VBox;
Gtk::Grid m_Grid;
Gtk::Label m_NameLabel;
Gtk::Entry m_NameEntry;
Gtk::Label m_SurnameLabel;
Gtk::Entry m_SurnameEntry;
Gtk::Label m_CommentsLabel;
Gtk::ScrolledWindow m_ScrolledWindow;
Gtk::TextView m_TextView;
Glib::RefPtr<Gtk::TextBuffer> m_refTextBuffer;
unsigned m_ContextId;
Gtk::Statusbar m_Statusbar;
Glib::RefPtr<Gtk::Builder> m_refBuilder;
};
#endif //GTKMM_EXAMPLEWINDOW_H
</pre>
<p>File: <code class="filename">printformoperation.h</code> (For use with gtkmm 3, not gtkmm 2)
</p>
<pre class="programlisting">
#ifndef GTKMM_PRINT_FORM_OPERATION_H
#define GTKMM_PRINT_FORM_OPERATION_H
#include <gtkmm.h>
#include <pangomm.h>
#include <vector>
//We derive our own class from PrintOperation,
//so we can put the actual print implementation here.
class PrintFormOperation : public Gtk::PrintOperation
{
public:
static Glib::RefPtr<PrintFormOperation> create();
virtual ~PrintFormOperation();
void set_name(const Glib::ustring& name) { m_Name = name; }
void set_comments(const Glib::ustring& comments) { m_Comments = comments; }
protected:
PrintFormOperation();
//PrintOperation default signal handler overrides:
void on_begin_print(const Glib::RefPtr<Gtk::PrintContext>& context) override;
void on_draw_page(const Glib::RefPtr<Gtk::PrintContext>& context, int page_nr) override;
Glib::ustring m_Name;
Glib::ustring m_Comments;
Glib::RefPtr<Pango::Layout> m_refLayout;
std::vector<int> m_PageBreaks; // line numbers where a page break occurs
};
#endif // GTKMM_PRINT_FORM_OPERATION_H
</pre>
<p>File: <code class="filename">main.cc</code> (For use with gtkmm 3, not gtkmm 2)
</p>
<pre class="programlisting">
#include "examplewindow.h"
#include <gtkmm/application.h>
int main(int argc, char* argv[])
{
auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");
ExampleWindow window(app);
// Shows the window and returns when it is closed.
return app->run(window);
}
</pre>
<p>File: <code class="filename">examplewindow.cc</code> (For use with gtkmm 3, not gtkmm 2)
</p>
<pre class="programlisting">
#include "examplewindow.h"
#include "printformoperation.h"
#include <iostream>
const Glib::ustring app_title = "gtkmm Printing Example";
ExampleWindow::ExampleWindow(const Glib::RefPtr<Gtk::Application>& app)
: m_VBox(Gtk::ORIENTATION_VERTICAL),
m_NameLabel("Name"),
m_SurnameLabel("Surname"),
m_CommentsLabel("Comments")
{
m_refPageSetup = Gtk::PageSetup::create();
m_refSettings = Gtk::PrintSettings::create();
m_ContextId = m_Statusbar.get_context_id(app_title);
set_title(app_title);
set_default_size(400, 300);
add(m_VBox);
build_main_menu(app);
m_VBox.pack_start(m_Grid);
//Arrange the widgets inside the grid:
m_Grid.set_row_spacing(5);
m_Grid.set_column_spacing(5);
m_Grid.attach(m_NameLabel, 0, 0, 1, 1);
m_Grid.attach(m_NameEntry, 1, 0, 1, 1);
m_Grid.attach(m_SurnameLabel, 0, 1, 1, 1);
m_Grid.attach(m_SurnameEntry, 1, 1, 1, 1);
//Add the TextView, inside a ScrolledWindow:
m_ScrolledWindow.add(m_TextView);
//Only show the scrollbars when they are necessary:
m_ScrolledWindow.set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_AUTOMATIC);
m_Grid.attach(m_CommentsLabel, 0, 2, 1, 1);
m_Grid.attach(m_ScrolledWindow, 1, 2, 1, 1);
m_ScrolledWindow.set_hexpand(true);
m_ScrolledWindow.set_vexpand(true);
m_refTextBuffer = Gtk::TextBuffer::create();
m_TextView.set_buffer(m_refTextBuffer);
m_VBox.pack_start(m_Statusbar);
show_all_children();
}
ExampleWindow::~ExampleWindow()
{
}
void ExampleWindow::build_main_menu(const Glib::RefPtr<Gtk::Application>& app)
{
//Create actions for menus and toolbars:
auto refActionGroup = Gio::SimpleActionGroup::create();
//File menu:
refActionGroup->add_action("new",
sigc::mem_fun(*this, &ExampleWindow::on_menu_file_new));
refActionGroup->add_action("pagesetup",
sigc::mem_fun(*this, &ExampleWindow::on_menu_file_page_setup));
refActionGroup->add_action("printpreview",
sigc::mem_fun(*this, &ExampleWindow::on_menu_file_print_preview));
refActionGroup->add_action("print",
sigc::mem_fun(*this, &ExampleWindow::on_menu_file_print));
refActionGroup->add_action("quit",
sigc::mem_fun(*this, &ExampleWindow::on_menu_file_quit));
insert_action_group("example", refActionGroup);
// When the menubar is a child of a Gtk::Window, keyboard accelerators are not
// automatically fetched from the Gio::Menu.
// See the examples/book/menus/main_menu example for an alternative way of
// adding the menubar when using Gtk::ApplicationWindow.
app->set_accel_for_action("example.new", "<Primary>n");
app->set_accel_for_action("example.print", "<Primary>p");
app->set_accel_for_action("example.quit", "<Primary>q");
m_refBuilder = Gtk::Builder::create();
// Layout the actions in a menubar:
Glib::ustring ui_menu_info =
"<interface>"
" <menu id='menu-example'>"
" <submenu>"
" <attribute name='label' translatable='yes'>_File</attribute>"
" <section>"
" <item>"
" <attribute name='label' translatable='yes'>_New</attribute>"
" <attribute name='action'>example.new</attribute>"
" </item>"
" </section>"
" <section>"
" <item>"
" <attribute name='label' translatable='yes'>Page _Setup...</attribute>"
" <attribute name='action'>example.pagesetup</attribute>"
" </item>"
" <item>"
" <attribute name='label' translatable='yes'>Print Preview</attribute>"
" <attribute name='action'>example.printpreview</attribute>"
" </item>"
" <item>"
" <attribute name='label' translatable='yes'>_Print...</attribute>"
" <attribute name='action'>example.print</attribute>"
" </item>"
" </section>"
" <section>"
" <item>"
" <attribute name='label' translatable='yes'>_Quit</attribute>"
" <attribute name='action'>example.quit</attribute>"
" </item>"
" </section>"
" </submenu>"
" </menu>"
"</interface>";
try
{
m_refBuilder->add_from_string(ui_menu_info);
}
catch(const Glib::Error& ex)
{
std::cerr << "building menus failed: " << ex.what();
}
// Layout the actions in a toolbar:
Glib::ustring ui_toolbar_info =
"<!-- Generated with glade 3.18.3 -->"
"<interface>"
"<requires lib='gtk+' version='3.8'/>"
"<object class='GtkToolbar' id='toolbar'>"
"<property name='visible'>True</property>"
"<property name='can_focus'>False</property>"
"<child>"
"<object class='GtkToolButton' id='toolbutton_new'>"
"<property name='visible'>True</property>"
"<property name='can_focus'>False</property>"
"<property name='tooltip_text' translatable='yes'>New</property>"
"<property name='action_name'>example.new</property>"
"<property name='icon_name'>document-new</property>"
"</object>"
"<packing>"
"<property name='expand'>False</property>"
"<property name='homogeneous'>True</property>"
"</packing>"
"</child>"
"<child>"
"<object class='GtkToolButton' id='toolbutton_print'>"
"<property name='visible'>True</property>"
"<property name='can_focus'>False</property>"
"<property name='tooltip_text' translatable='yes'>Print</property>"
"<property name='action_name'>example.print</property>"
"<property name='icon_name'>document-print</property>"
"</object>"
"<packing>"
"<property name='expand'>False</property>"
"<property name='homogeneous'>True</property>"
"</packing>"
"</child>"
"<child>"
"<object class='GtkSeparatorToolItem' id='separator1'>"
"<property name='visible'>True</property>"
"<property name='can_focus'>False</property>"
"</object>"
"<packing>"
"<property name='expand'>False</property>"
"<property name='homogeneous'>False</property>"
"</packing>"
"</child>"
"<child>"
"<object class='GtkToolButton' id='toolbutton_quit'>"
"<property name='visible'>True</property>"
"<property name='can_focus'>False</property>"
"<property name='tooltip_text' translatable='yes'>Quit</property>"
"<property name='action_name'>example.quit</property>"
"<property name='icon_name'>application-exit</property>"
"</object>"
"<packing>"
"<property name='expand'>False</property>"
"<property name='homogeneous'>True</property>"
"</packing>"
"</child>"
"</object>"
"</interface>";
try
{
m_refBuilder->add_from_string(ui_toolbar_info);
}
catch(const Glib::Error& ex)
{
std::cerr << "building toolbar failed: " << ex.what();
}
// Get the menubar and add it to a container widget:
auto object = m_refBuilder->get_object("menu-example");
auto gmenu = Glib::RefPtr<Gio::Menu>::cast_dynamic(object);
if (!gmenu)
g_warning("GMenu not found");
else
{
auto pMenuBar = Gtk::make_managed<Gtk::MenuBar>(gmenu);
// Add the MenuBar to the window:
m_VBox.pack_start(*pMenuBar, Gtk::PACK_SHRINK);
}
// Get the toolbar and add it to a container widget:
Gtk::Toolbar* toolbar = nullptr;
m_refBuilder->get_widget("toolbar", toolbar);
if (!toolbar)
g_warning("GtkToolbar not found");
else
m_VBox.pack_start(*toolbar, Gtk::PACK_SHRINK);
}
void ExampleWindow::on_printoperation_status_changed()
{
Glib::ustring status_msg;
if (m_refPrintFormOperation->is_finished())
{
status_msg = "Print job completed.";
}
else
{
//You could also use get_status().
status_msg = m_refPrintFormOperation->get_status_string();
}
m_Statusbar.push(status_msg, m_ContextId);
}
void ExampleWindow::on_printoperation_done(Gtk::PrintOperationResult result)
{
//Printing is "done" when the print data is spooled.
if (result == Gtk::PRINT_OPERATION_RESULT_ERROR)
{
Gtk::MessageDialog err_dialog(*this, "Error printing form", false,
Gtk::MESSAGE_ERROR, Gtk::BUTTONS_OK, true);
err_dialog.run();
}
else if (result == Gtk::PRINT_OPERATION_RESULT_APPLY)
{
//Update PrintSettings with the ones used in this PrintOperation:
m_refSettings = m_refPrintFormOperation->get_print_settings();
}
if (!m_refPrintFormOperation->is_finished())
{
//We will connect to the status-changed signal to track status
//and update a status bar. In addition, you can, for example,
//keep a list of active print operations, or provide a progress dialog.
m_refPrintFormOperation->signal_status_changed().connect(sigc::mem_fun(*this,
&ExampleWindow::on_printoperation_status_changed));
}
}
void ExampleWindow::print_or_preview(Gtk::PrintOperationAction print_action)
{
//Create a new PrintOperation with our PageSetup and PrintSettings:
//(We use our derived PrintOperation class)
m_refPrintFormOperation = PrintFormOperation::create();
m_refPrintFormOperation->set_name(m_NameEntry.get_text() + " " + m_SurnameEntry.get_text());
m_refPrintFormOperation->set_comments(m_refTextBuffer->get_text(false /*Don't include hidden*/));
// In the printing/advanced example, the font will be set through a custom tab
// in the print dialog.
m_refPrintFormOperation->set_track_print_status();
m_refPrintFormOperation->set_default_page_setup(m_refPageSetup);
m_refPrintFormOperation->set_print_settings(m_refSettings);
m_refPrintFormOperation->signal_done().connect(sigc::mem_fun(*this,
&ExampleWindow::on_printoperation_done));
try
{
m_refPrintFormOperation->run(print_action /* print or preview */, *this);
}
catch (const Gtk::PrintError& ex)
{
//See documentation for exact Gtk::PrintError error codes.
std::cerr << "An error occurred while trying to run a print operation:"
<< ex.what() << std::endl;
}
}
void ExampleWindow::on_menu_file_new()
{
//Clear entries and textview:
m_NameEntry.set_text("");
m_SurnameEntry.set_text("");
m_refTextBuffer->set_text("");
m_TextView.set_buffer(m_refTextBuffer);
}
void ExampleWindow::on_menu_file_page_setup()
{
//Show the page setup dialog, asking it to start with the existing settings:
auto new_page_setup =
Gtk::run_page_setup_dialog(*this, m_refPageSetup, m_refSettings);
//Save the chosen page setup dialog for use when printing, previewing, or
//showing the page setup dialog again:
m_refPageSetup = new_page_setup;
}
void ExampleWindow::on_menu_file_print_preview()
{
print_or_preview(Gtk::PRINT_OPERATION_ACTION_PREVIEW);
}
void ExampleWindow::on_menu_file_print()
{
print_or_preview(Gtk::PRINT_OPERATION_ACTION_PRINT_DIALOG);
}
void ExampleWindow::on_menu_file_quit()
{
hide();
}
</pre>
<p>File: <code class="filename">printformoperation.cc</code> (For use with gtkmm 3, not gtkmm 2)
</p>
<pre class="programlisting">
#include "printformoperation.h"
PrintFormOperation::PrintFormOperation()
{
}
PrintFormOperation::~PrintFormOperation()
{
}
Glib::RefPtr<PrintFormOperation> PrintFormOperation::create()
{
return Glib::RefPtr<PrintFormOperation>(new PrintFormOperation());
}
void PrintFormOperation::on_begin_print(
const Glib::RefPtr<Gtk::PrintContext>& print_context)
{
//Create and set up a Pango layout for PrintData based on the passed
//PrintContext: We then use this to calculate the number of pages needed, and
//the lines that are on each page.
m_refLayout = print_context->create_pango_layout();
Pango::FontDescription font_desc("sans 12");
m_refLayout->set_font_description(font_desc);
const double width = print_context->get_width();
const double height = print_context->get_height();
m_refLayout->set_width(static_cast<int>(width * Pango::SCALE));
//Set and mark up the text to print:
Glib::ustring marked_up_form_text;
marked_up_form_text += "<b>Name</b>: " + m_Name + "\n\n";
marked_up_form_text += "<b>Comments</b>: " + m_Comments;
m_refLayout->set_markup(marked_up_form_text);
//Set the number of pages to print by determining the line numbers
//where page breaks occur:
const int line_count = m_refLayout->get_line_count();
Glib::RefPtr<Pango::LayoutLine> layout_line;
double page_height = 0;
for (int line = 0; line < line_count; ++line)
{
Pango::Rectangle ink_rect, logical_rect;
layout_line = m_refLayout->get_line(line);
layout_line->get_extents(ink_rect, logical_rect);
const double line_height = logical_rect.get_height() / 1024.0;
if (page_height + line_height > height)
{
m_PageBreaks.push_back(line);
page_height = 0;
}
page_height += line_height;
}
set_n_pages(m_PageBreaks.size() + 1);
}
void PrintFormOperation::on_draw_page(
const Glib::RefPtr<Gtk::PrintContext>& print_context, int page_nr)
{
//Decide which lines we need to print in order to print the specified page:
int start_page_line = 0;
int end_page_line = 0;
if(page_nr == 0)
{
start_page_line = 0;
}
else
{
start_page_line = m_PageBreaks[page_nr - 1];
}
if(page_nr < static_cast<int>(m_PageBreaks.size()))
{
end_page_line = m_PageBreaks[page_nr];
}
else
{
end_page_line = m_refLayout->get_line_count();
}
//Get a Cairo Context, which is used as a drawing board:
Cairo::RefPtr<Cairo::Context> cairo_ctx = print_context->get_cairo_context();
//We'll use black letters:
cairo_ctx->set_source_rgb(0, 0, 0);
//Render Pango LayoutLines over the Cairo context:
Pango::LayoutIter iter = m_refLayout->get_iter();
double start_pos = 0;
int line_index = 0;
do
{
if(line_index >= start_page_line)
{
auto layout_line = iter.get_line();
Pango::Rectangle logical_rect = iter.get_line_logical_extents();
int baseline = iter.get_baseline();
if (line_index == start_page_line)
{
start_pos = logical_rect.get_y() / 1024.0;
}
cairo_ctx->move_to(logical_rect.get_x() / 1024.0,
baseline / 1024.0 - start_pos);
layout_line->show_in_cairo_context(cairo_ctx);
}
line_index++;
}
while(line_index < end_page_line && iter.next_line());
}
</pre>
</div>
</div>
<div class="navfooter">
<hr>
<table width="100%" summary="Navigation footer">
<tr>
<td width="40%" align="left">
<a accesskey="p" href="sec-printing-preview.html"><img src="icons/prev.png" alt="Prev"></a> </td>
<td width="20%" align="center"><a accesskey="u" href="chapter-printing.html"><img src="icons/up.png" alt="Up"></a></td>
<td width="40%" align="right"> <a accesskey="n" href="chapter-recent-documents.html"><img src="icons/next.png" alt="Next"></a>
</td>
</tr>
<tr>
<td width="40%" align="left" valign="top">Preview </td>
<td width="20%" align="center"><a accesskey="h" href="index.html"><img src="icons/home.png" alt="Home"></a></td>
<td width="40%" align="right" valign="top"> Chapter 21. Recently Used Documents</td>
</tr>
</table>
</div>
</body>
</html>
