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diff --git a/doc/src/examples/qxmlstreambookmarks.qdoc b/doc/src/examples/qxmlstreambookmarks.qdoc new file mode 100644 index 0000000..7059043 --- /dev/null +++ b/doc/src/examples/qxmlstreambookmarks.qdoc @@ -0,0 +1,200 @@ +/**************************************************************************** +** +** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). +** Contact: Qt Software Information (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 qt-sales@nokia.com. +** $QT_END_LICENSE$ +** +****************************************************************************/ + +/*! + \example xml/streambookmarks + \title QXmlStream Bookmarks Example + + The QXmlStream Bookmarks example provides a reader for XML Bookmark + Exchange Language (XBEL) files using Qt's QXmlStreamReader class + for reading, and QXmlStreamWriter class for writing the files. + + \image xmlstreamexample-screenshot.png + + \section1 XbelWriter Class Definition + + The \c XbelWriter class is a subclass of QXmlStreamReader, which provides + an XML parser with a streaming API. \c XbelWriter also contains a private + instance of QTreeWidget in order to display the bookmarks according to + hierarchies. + + \snippet examples/xml/streambookmarks/xbelwriter.h 0 + + \section1 XbelWriter Class Implementation + + The \c XbelWriter constructor accepts a \a treeWidget to initialize within + its definition. We enable \l{QXmlStreamWriter}'s auto-formatting property + to ensure line-breaks and indentations are added automatically to empty + sections between elements, increasing readability as the data is split into + several lines. + + \snippet examples/xml/streambookmarks/xbelwriter.cpp 0 + + The \c writeFile() function accepts a QIODevice object and sets it using + \c setDevice(). This function then writes the document type + definition(DTD), the start element, the version, and \c{treeWidget}'s + top-level items. + + \snippet examples/xml/streambookmarks/xbelwriter.cpp 1 + + The \c writeItem() function accepts a QTreeWidget object and writes it + to the stream, depending on its \c tagName, which can either be a "folder", + "bookmark", or "separator". + + \snippet examples/xml/streambookmarks/xbelwriter.cpp 2 + + \section1 XbelReader Class Definition + + The \c XbelReader class is a subclass of QXmlStreamReader, the pendent + class for QXmlStreamWriter. \c XbelReader contains a private instance + of QTreeWidget to group bookmarks according to their hierarchies. + + \snippet examples/xml/streambookmarks/xbelreader.h 0 + + \section1 XbelReader Class Implementation + + The \c XbelReader constructor accepts a QTreeWidget to initialize the + \c treeWidget within its definition. A QStyle object is used to set + \c{treeWidget}'s style property. The \c folderIcon is set to QIcon::Normal + mode where the pixmap is only displayed when the user is not interacting + with the icon. The QStyle::SP_DirClosedIcon, QStyle::SP_DirOpenIcon, and + QStyle::SP_FileIcon correspond to standard pixmaps that follow the style + of your GUI. + + \snippet examples/xml/streambookmarks/xbelreader.cpp 0 + + The \c read() function accepts a QIODevice and sets it using + \l{QXmlStreamReader::setDevice()}{setDevice()}. The actual process + of reading only takes place in event the file is a valid XBEL 1.0 + file. Otherwise, the \l{QXmlStreamReader::raiseError()} + {raiseError()} function is used to display an error message. + + \snippet examples/xml/streambookmarks/xbelreader.cpp 1 + + The \c readUnknownElement() function reads an unknown element. The + Q_ASSERT() macro is used to provide a pre-condition for the function. + + \snippet examples/xml/streambookmarks/xbelreader.cpp 2 + + The \c readXBEL() function reads the name of a startElement and calls + the appropriate function to read it, depending on whether if its a + "folder", "bookmark" or "separator". Otherwise, it calls + \c readUnknownElement(). + + \snippet examples/xml/streambookmarks/xbelreader.cpp 3 + + The \c readTitle() function reads the bookmark's title. + + \snippet examples/xml/streambookmarks/xbelreader.cpp 4 + + The \c readSeparator() function creates a separator and sets its flags. + The text is set to 30 "0xB7", the HEX equivalent for period, and then + read using \c readElementText(). + + \snippet examples/xml/streambookmarks/xbelreader.cpp 5 + + \section1 MainWindow Class Definition + + The \c MainWindow class is a subclass of QMainWindow, with a + \c File menu and a \c Help menu. + + \snippet examples/xml/streambookmarks/mainwindow.h 0 + + \section1 MainWindow Class Implementation + + The \c MainWindow constructor instantiates the QTreeWidget object, \c + treeWidget and sets its header with a QStringList object, \c labels. + The constructor also invokes \c createActions() and \c createMenus() + to set up the menus and their corresponding actions. The \c statusBar() + is used to display the message "Ready" and the window's size is fixed + to 480x320 pixels. + + \snippet examples/xml/streambookmarks/mainwindow.cpp 0 + + The \c open() function enables the user to open an XBEL file using + QFileDialog::getOpenFileName(). A warning message is displayed along + with the \c fileName and \c errorString if the file cannot be read or + if there is a parse error. + + \snippet examples/xml/streambookmarks/mainwindow.cpp 1 + + The \c saveAs() function displays a QFileDialog, prompting the user for + a \c fileName using QFileDialog::getSaveFileName(). Similar to the + \c open() function, this function also displays a warning message if + the file cannot be written to. + + \snippet examples/xml/streambookmarks/mainwindow.cpp 2 + + The \c about() function displays a QMessageBox with a brief description + of the example. + + \snippet examples/xml/streambookmarks/mainwindow.cpp 3 + + In order to implement the \c open(), \c saveAs(), \c exit(), \c about() + and \c aboutQt() functions, we connect them to QAction objects and + add them to the \c fileMenu and \c helpMenu. The connections are as shown + below: + + \snippet examples/xml/streambookmarks/mainwindow.cpp 4 + + The \c createMenus() function creates the \c fileMenu and \c helpMenu + and adds the QAction objects to them in order to create the menu shown + in the screenshot below: + + \table + \row + \o \inlineimage xmlstreamexample-filemenu.png + \o \inlineimage xmlstreamexample-helpmenu.png + \endtable + + \snippet examples/xml/streambookmarks/mainwindow.cpp 5 + + \section1 \c{main()} Function + + The \c main() function instantiates \c MainWindow and invokes the \c show() + function. + + \snippet examples/xml/streambookmarks/main.cpp 0 + + See the \l{http://pyxml.sourceforge.net/topics/xbel/} + {XML Bookmark Exchange Language Resource Page} for more information + about XBEL files. +*/ |