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diff --git a/doc/src/painting-and-printing/printing.qdoc b/doc/src/painting-and-printing/printing.qdoc new file mode 100644 index 0000000..291286e --- /dev/null +++ b/doc/src/painting-and-printing/printing.qdoc @@ -0,0 +1,191 @@ +/**************************************************************************** +** +** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). +** Contact: Nokia Corporation (qt-info@nokia.com) +** +** This file is part of the documentation of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the either Technology Preview License Agreement or the +** Beta Release License Agreement. +** +** GNU Lesser General Public License Usage +** Alternatively, this file may be used under the terms of the GNU Lesser +** General Public License version 2.1 as published by the Free Software +** Foundation and appearing in the file LICENSE.LGPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU Lesser General Public License version 2.1 requirements +** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Nokia gives you certain +** additional rights. These rights are described in the Nokia Qt LGPL +** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this +** package. +** +** GNU General Public License Usage +** Alternatively, this file may be used under the terms of the GNU +** General Public License version 3.0 as published by the Free Software +** Foundation and appearing in the file LICENSE.GPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU General Public License version 3.0 requirements will be +** met: http://www.gnu.org/copyleft/gpl.html. +** +** If you are unsure which license is appropriate for your use, please +** contact the sales department at http://qt.nokia.com/contact. +** $QT_END_LICENSE$ +** +****************************************************************************/ + +/*! + \group printing + \title Printer and Printing APIs + \brief Classes for producing printed output + \ingroup groups +*/ + +/*! + \page printing.html + \title Printing with Qt + + \previouspage Styling + \contentspage The Paint System + + \brief A guide to producing printed output with Qt's paint system and widgets. + + Qt provides extensive cross-platform support for printing. Using the printing + systems on each platform, Qt applications can print to attached printers and + across networks to remote printers. Qt's printing system also enables PostScript + and PDF files to be generated, providing the foundation for basic report + generation facilities. + + \tableofcontents + + \section1 Classes Supporting Printing + + The following classes support the selecting and setting up of printers and + printing output. + + \annotatedlist printing + + \section1 Paint Devices and Printing + + In Qt, printers are represented by QPrinter, a paint device that provides + functionality specific to printing, such as support for multiple pages and + double-sided output. As a result, printing involves using a QPainter to paint + onto a series of pages in the same way that you would paint onto a custom + widget or image. + + \section2 Creating a QPrinter + + Although QPrinter objects can be constructed and set up without requiring user + input, printing is often performed as a result of a request by the user; + for example, when the user selects the \gui{File|Print...} menu item in a GUI + application. In such cases, a newly-constructed QPrinter object is supplied to + a QPrintDialog, allowing the user to specify the printer to use, paper size, and + other printing properties. + + \snippet examples/richtext/orderform/mainwindow.cpp 18 + + It is also possible to set certain default properties by modifying the QPrinter + before it is supplied to the print dialog. For example, applications that + generate batches of reports for printing may set up the QPrinter to + \l{QPrinter::setOutputFileName()}{write to a local file} by default rather than + to a printer. + + \section2 Painting onto a Page + + Once a QPrinter object has been constructed and set up, a QPainter can be used + to perform painting operations on it. We can construct and set up a painter in + the following way: + + \snippet doc/src/snippets/printing-qprinter/object.cpp 0 + + Since the QPrinter starts with a blank page, we only need to call the + \l{QPrinter::}{newPage()} function after drawing each page, except for the + last page. + + The document is sent to the printer, or written to a local file, when we call + \l{QPainter::}{end()}. + + \section2 Coordinate Systems + + QPrinter provides functions that can be used to obtain information about the + dimensions of the paper (the paper rectangle) and the dimensions of the + printable area (the page rectangle). These are given in logical device + coordinates that may differ from the physical coordinates used by the device + itself, indicating that the printer is able to render text and graphics at a + (typically higher) resolution than the user's display. + + Although we do not need to handle the conversion between logical and physical + coordinates ourselves, we still need to apply transformations to painting + operations because the pixel measurements used to draw on screen are often + too small for the higher resolutions of typical printers. + + \table + \row \o \bold{Printer and Painter Coordinate Systems} + + The \l{QPrinter::}{paperRect()} and \l{QPrinter::}{pageRect()} functions + provide information about the size of the paper used for printing and the + area on it that can be painted on. + + The rectangle returned by \l{QPrinter::}{pageRect()} usually lies inside + the rectangle returned by \l{QPrinter::}{paperRect()}. You do not need to + take the positions and sizes of these area into account when using a QPainter + with a QPrinter as the underlying paint device; the origin of the painter's + coordinate system will coincide with the top-left corner of the page + rectangle, and painting operations will be clipped to the bounds of the + drawable part of the page. + + \o \inlineimage printer-rects.png + \endtable + + The paint system automatically uses the correct device metrics when painting + text but, if you need to position text using information obtained from + font metrics, you need to ensure that the print device is specified when + you construct QFontMetrics and QFontMetricsF objects, or ensure that each QFont + used is constructed using the form of the constructor that accepts a + QPaintDevice argument. + + \section1 Printing from Complex Widgets + + Certain widgets, such as QTextEdit and QGraphicsView, display rich content + that is typically managed by instances of other classes, such as QTextDocument + and QGraphicsScene. As a result, it is these content handling classes that + usually provide printing functionality, either via a function that can be used + to perform the complete task, or via a function that accepts an existing + QPainter object. Some widgets provide convenience functions to expose underlying + printing features, avoiding the need to obtain the content handler just to call + a single function. + + The following table shows which class and function are responsible for + printing from a selection of different widgets. For widgets that do not expose + printing functionality directly, the content handling classes containing this + functionality can be obtained via a function in the corresponding widget's API. + + \table + \header \o Widget \o Printing function \o Accepts + \row \o QGraphicsView \o QGraphicsView::render() \o QPainter + \row \o QSvgWidget \o QSvgRenderer::render() \o QPainter + \row \o QTextEdit \o QTextDocument::print() \o QPrinter + \row \o QTextLayout \o QTextLayout::draw() \o QPainter + \row \o QTextLine \o QTextLine::draw() \o QPainter + \endtable + + QTextEdit requires a QPrinter rather than a QPainter because it uses information + about the configured page dimensions in order to insert page breaks at the most + appropriate places in printed documents. +*/ + +/*! + \page pdf-licensing.html + \title Notes about PDF Licensing + \ingroup licensing + \brief Details of restrictions on the use of PDF-related trademarks. + + Please note that Adobe\reg places restrictions on the use of its trademarks + (including logos) in conjunction with PDF; e.g. "Adobe PDF". Please refer + to \l{http://www.adobe.com}{www.adobe.com} for guidelines. +*/ |