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authorJerome Pasion <jerome.pasion@digia.com>2012-11-22 16:35:24 +0100
committerThe Qt Project <gerrit-noreply@qt-project.org>2012-11-23 13:16:20 +0100
commit051aeb291646745559c47da160193bdcbd34ef2b (patch)
tree50040152b4dfe22238ef0446c9e57ff1b345bdd4 /examples
parentb34af22fcc7e9321e5a7943763cd68a1d51a36d5 (diff)
downloadqtxmlpatterns-051aeb291646745559c47da160193bdcbd34ef2b.tar.gz
Doc: Modularized Qt XML Patterns documentation.
-moved snippets, images, documentation to src/xmlpatterns -fixed \snippet tag -ported module information from qtdoc repository -enabled "make docs" for the module -set up qdocconf file and .index file -updated tests/auto/patternistexamples to point to the new snippet locations Change-Id: Ifd10733c277c6dbacac42898c8e7bacd00d23f27 Reviewed-by: Lars Knoll <lars.knoll@digia.com>
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-rw-r--r--examples/xmlpatterns/recipes/doc/src/recipes.qdoc150
-rw-r--r--examples/xmlpatterns/schema/doc/src/schema.qdoc129
-rw-r--r--examples/xmlpatterns/trafficinfo/doc/src/trafficinfo.qdoc149
-rw-r--r--examples/xmlpatterns/xquery/doc/src/globalVariables.qdoc201
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+/****************************************************************************
+**
+** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:FDL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Free Documentation License Usage
+** Alternatively, this file may be used under the terms of the GNU Free
+** Documentation License version 1.3 as published by the Free Software
+** Foundation and appearing in the file included in the packaging of
+** this file. Please review the following information to ensure
+** the GNU Free Documentation License version 1.3 requirements
+** will be met: http://www.gnu.org/copyleft/fdl.html.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+ \example xmlpatterns/filetree
+ \title File System Example
+
+ This example shows how to use Qt XML Patterns for querying non-XML
+ data that is modeled to look like XML.
+
+ \tableofcontents
+
+ \section1 Introduction
+
+ The example models your computer's file system to look like XML and
+ allows you to query the file system with XQuery. Suppose we want to
+ find all the \c{cpp} files in the subtree beginning at
+ \c{/filetree}:
+
+ \image filetree_1-example.png
+
+ \section2 The User Inteface
+
+ The example is shown below. First, we use \c{File->Open Directory}
+ (not shown) to select the \c{/filetree} directory. Then we use the
+ combobox on the right to select the XQuery that searches for \c{cpp}
+ files (\c{listCPPFiles.xq}). Selecting an XQuery runs the query,
+ which in this case traverses the model looking for all the \c{cpp}
+ files. The XQuery text and the query results are shown on the right:
+
+ \image filetree_2-example.png
+
+ Don't be mislead by the XML representation of the \c{/filetree}
+ directory shown on the left. This is not the node model itself but
+ the XML obtained by traversing the node model and outputting it as
+ XML. Constructing and using the custom node model is explained in
+ the code walk-through.
+
+ \section2 Running your own XQueries
+
+ You can write your own XQuery files and run them in the example
+ program. The file \c{xmlpatterns/filetree/queries.qrc} is the \l{The
+ Qt Resource System} {resource file} for this example. It is used in
+ \c{main.cpp} (\c{Q_INIT_RESOURCE(queries);}). It lists the XQuery
+ files (\c{.xq}) that can be selected in the combobox.
+
+ \quotefromfile xmlpatterns/filetree/queries.qrc
+ \printuntil
+
+ To add your own queries to the example's combobox, store your
+ \c{.xq} files in the \c{examples/xmlpatterns/filetree/queries}
+ directory and add them to \c{queries.qrc} as shown above.
+
+ \section1 Code Walk-Through
+
+ The strategy is to create a custom node model that represents the
+ directory tree of the computer's file system. That tree structure is
+ non-XML data. The custom node model must have the same callback
+ interface as the XML node models that the Qt XML Patterns query engine
+ uses to execute queries. The query engine can then traverse the
+ custom node model as if it were traversing the node model built from
+ an XML document.
+
+ The required callback interface is in QAbstractXmlNodeModel, so we
+ create a custom node model by subclassing QAbstractXmlNodeModel and
+ providing implementations for its pure virtual functions. For many
+ cases, the implementations of several of the virtual functions are
+ always the same, so Qt XML Patterns also provides QSimpleXmlNodeModel,
+ which subclasses QAbstractXmlNodeModel and provides implementations
+ for the callback functions that you can ignore. By subclassing
+ QSimpleXmlNodeModel instead of QAbstractXmlNodeModel, you can reduce
+ development time.
+
+ \section2 The Custom Node Model Class: FileTree
+
+ The custom node model for this example is class \c{FileTree}, which
+ is derived from QSimpleXmlNodeModel. \c{FileTree} implements all the
+ callback functions that don't have standard implementations in
+ QSimpleXmlNodeModel. When you implement your own custom node model,
+ you must provide implementations for these callback functions:
+
+ \snippet xmlpatterns/filetree/filetree.h 0
+ \snippet xmlpatterns/filetree/filetree.h 1
+
+ The \c{FileTree} class declares four data members:
+
+ \snippet xmlpatterns/filetree/filetree.h 2
+
+ The QVector \c{m_fileInfos} will contain the node model. Each
+ QFileInfo in the vector will represent a file or a directory in the
+ file system. At this point it is instructive to note that although
+ the node model class for this example (\c{FileTree}) actually builds
+ and contains the custom node model, building the custom node model
+ isn't always required. The node model class for the \l{QObject XML
+ Model Example} {QObject node model example} does not build its node
+ model but instead uses an already existing QObject tree as its node
+ model and just implements the callback interface for that already
+ existing data structure. In this file system example, however,
+ although we have an already existing data structure, i.e. the file
+ system, that data structure is not in memory and is not in a form we
+ can use. So we must build an analog of the file system in memory
+ from instances of QFileInfo, and we use that analog as the custom
+ node model.
+
+ The two sets of flags, \c{m_filterAllowAll} and \c{m_sortFlags},
+ contain OR'ed flags from QDir::Filters and QDir::SortFlags
+ respectively. They are set by the \c{FileTree} constructor and used
+ in calls to QDir::entryInfoList() for getting the child list for a
+ directory node, i.e. a QFileInfoList containing the file and
+ directory nodes for all the immediate children of a directory.
+
+ The QVector \c{m_names} is an auxiliary component of the node
+ model. It holds the XML element and attribute names (QXmlName) for
+ all the node types that will be found in the node model. \c{m_names}
+ is indexed by the enum \c{FileTree::Type}, which specifies the node
+ types:
+
+ \target Node_Type
+ \snippet xmlpatterns/filetree/filetree.h 4
+
+ \c{Directory} and \c{File} will represent the XML element nodes for
+ directories and files respectively, and the other enum values will
+ represent the XML attribute nodes for a file's path, name, suffix,
+ its size in bytes, and its mime type. The \c{FileTree} constructor
+ initializes \c{m_names} with an appropriate QXmlName for each
+ element and attribute type:
+
+ \snippet xmlpatterns/filetree/filetree.cpp 2
+
+ Note that the constructor does \e{not} pre-build the entire node
+ model. Instead, the node model is built \e{incrementally} as the
+ query engine evaluates a query. To see how the query engine causes
+ the node model to be built incrementally, see \l{Building And
+ Traversing The Node Model}. To see how the query engine accesses the
+ node model, see \l{Accessing the node model}. See also: \l{Node
+ Model Building Strategy}.
+
+ \section3 Accessing The Node Model
+
+ Since the node model is stored outside the query engine in the
+ \c{FileTree} class, the query engine knows nothing about it and can
+ only access it by calling functions in the callback interface. When
+ the query engine calls any callback function to access data in the
+ node model, it passes a QXmlNodeModelIndex to identify the node in
+ the node model that it wants to access. Hence all the virtual
+ functions in the callback interface use a QXmlNodeModelIndex to
+ uniquely identify a node in the model.
+
+ We use the index of a QFileInfo in \c{m_fileInfos} to uniquely
+ identify a node in the node model. To get the QXmlNodeModelIndex for
+ a QFileInfo, the class uses the private function \c{toNodeIndex()}:
+
+ \target main toNodeIndex
+ \snippet xmlpatterns/filetree/filetree.cpp 1
+
+ It searches the \c{m_fileInfos} vector for a QFileInfo that matches
+ \c{fileInfo}. If a match is found, its array index is passed to
+ QAbstractXmlNodeModel::createIndex() as the \c data value for the
+ QXmlNodeIndex. If no match is found, the unmatched QFileInfo is
+ appended to the vector, so this function is also doing the actual
+ incremental model building (see \l{Building And Traversing The Node
+ Model}).
+
+ Note that \c{toNodeIndex()} gets a \l{Node_Type} {node type} as the
+ second parameter, which it just passes on to
+ \l{QAbstractXmlNodeModel::createIndex()} {createIndex()} as the
+ \c{additionalData} value. Logically, this second parameter
+ represents a second dimension in the node model, where the first
+ dimension represents the \e element nodes, and the second dimension
+ represents each element's attribute nodes. The meaning is that each
+ QFileInfo in the \c{m_fileInfos} vector can represent an \e{element}
+ node \e{and} one or more \e{attribute} nodes. In particular, the
+ QFileInfo for a file will contain the values for the attribute nodes
+ path, name, suffix, size, and mime type (see
+ \c{FileTree::attributes()}). Since the attributes are contained in
+ the QFileInfo of the file element, there aren't actually any
+ attribute nodes in the node model. Hence, we can use a QVector for
+ \c{m_fileInfos}.
+
+ A convenience overloading of \l{toNodeIndex of convenience}
+ {toNodeIndex()} is also called in several places, wherever it is
+ known that the QXmlNodeModelIndex being requested is for a directory
+ or a file and not for an attribute. The convenience function takes
+ only the QFileInfo parameter and calls the other \l{main toNodeIndex}
+ {toNodeIndex()}, after obtaining either the Directory or File node
+ type directly from the QFileInfo:
+
+ \target toNodeIndex of convenience
+ \snippet xmlpatterns/filetree/filetree.cpp 0
+
+ Note that the auxiliary vector \c{m_names} is accessed using the
+ \l{Node_Type} {node type}, for example:
+
+ \snippet xmlpatterns/filetree/filetree.cpp 3
+
+ Most of the virtual functions in the callback interface are as
+ simple as the ones described so far, but the callback function used
+ for traversing (and building) the node model is more complex.
+
+ \section3 Building And Traversing The Node Model
+
+ The node model in \c{FileTree} is not fully built before the query
+ engine begins evaluating the query. In fact, when the query engine
+ begins evaluating its first query, the only node in the node model
+ is the one representing the root directory for the selected part of
+ the file system. See \l{The UI Class: MainWindow} below for details
+ about how the UI triggers creation of the model.
+
+ The query engine builds the node model incrementally each time it
+ calls the \l{next node on axis} {nextFromSimpleAxis()} callback
+ function, as it traverses the node model to evaluate a query. Thus
+ the query engine only builds the region of the node model that it
+ needs for evaluating the query.
+
+ \l{next node on axis} {nextFromSimpleAxis()} takes an
+ \l{QAbstractXmlNodeModel::SimpleAxis} {axis identifier} and a
+ \l{QXmlNodeModelIndex} {node identifier} as parameters. The
+ \l{QXmlNodeModelIndex} {node identifier} represents the \e{context
+ node} (i.e. the query engine's current location in the model), and
+ the \l{QAbstractXmlNodeModel::SimpleAxis} {axis identifier}
+ represents the direction we want to move from the context node. The
+ function finds the appropriate next node and returns its
+ QXmlNodeModelIndex.
+
+ \l{next node on axis} {nextFromSimpleAxis()} is where most of the
+ work of implementing a custom node model will be required. The
+ obvious way to do it is to use a switch statement with a case for
+ each \l{QAbstractXmlNodeModel::SimpleAxis} {axis}.
+
+ \target next node on axis
+ \snippet xmlpatterns/filetree/filetree.cpp 4
+
+ The first thing this function does is call \l{to file info}
+ {toFileInfo()} to get the QFileInfo of the context node. The use of
+ QVector::at() here is guaranteed to succeed because the context node
+ must already be in the node model, and hence must have a QFileInfo
+ in \c{m_fileInfos}.
+
+ \target to file info
+ \snippet xmlpatterns/filetree/filetree.cpp 6
+
+ The \l{QAbstractXmlNodeModel::Parent} {Parent} case looks up the
+ context node's parent by constructing a QFileInfo from the context
+ node's \l{QFileInfo::absoluteFilePath()} {path} and passing it to
+ \l{main toNodeIndex} {toNodeIndex()} to find the QFileInfo in
+ \c{m_fileInfos}.
+
+ The \l{QAbstractXmlNodeModel::FirstChild} {FirstChild} case requires
+ that the context node must be a directory, because a file doesn't
+ have children. If the context node is not a directory, a default
+ constructed QXmlNodeModelIndex is returned. Otherwise,
+ QDir::entryInfoList() constructs a QFileInfoList of the context
+ node's children. The first QFileInfo in the list is passed to
+ \l{toNodeIndex of convenience} {toNodeIndex()} to get its
+ QXmlNodeModelIndex. Note that this will add the child to the node
+ model, if it isn't in the model yet.
+
+ The \l{QAbstractXmlNodeModel::PreviousSibling} {PreviousSibling} and
+ \l{QAbstractXmlNodeModel::NextSibling} {NextSibling} cases call the
+ \l{nextSibling helper} {nextSibling() helper function}. It takes the
+ QXmlNodeModelIndex of the context node, the QFileInfo of the context
+ node, and an offest of +1 or -1. The context node is a child of some
+ parent, so the function gets the parent and then gets the child list
+ for the parent. The child list is searched to find the QFileInfo of
+ the context node. It must be there. Then the offset is applied, -1
+ for the previous sibling and +1 for the next sibling. The resulting
+ index is passed to \l{toNodeIndex of convenience} {toNodeIndex()} to
+ get its QXmlNodeModelIndex. Note again that this will add the
+ sibling to the node model, if it isn't in the model yet.
+
+ \target nextSibling helper
+ \snippet xmlpatterns/filetree/filetree.cpp 5
+
+ \section2 The UI Class: MainWindow
+
+ The example's UI is a conventional Qt GUI application inheriting
+ QMainWindow and the Ui_MainWindow base class generated by
+ \l{Qt Designer Manual} {Qt Designer}.
+
+ \snippet xmlpatterns/filetree/mainwindow.h 0
+
+ It contains the custom node model (\c{m_fileTree}) and an instance
+ of QXmlNodeModelIndex (\c{m_fileNode}) used for holding the node
+ index for the root of the file system subtree. \c{m_fileNode} will
+ be bound to a $variable in the XQuery to be evaluated.
+
+ Two actions of interest are handled by slot functions: \l{Selecting
+ A Directory To Model} and \l{Selecting And Running An XQuery}.
+
+ \section3 Selecting A Directory To Model
+
+ The user selects \c{File->Open Directory} to choose a directory to
+ be loaded into the custom node model. Choosing a directory signals
+ the \c{on_actionOpenDirectory_triggered()} slot:
+
+ \snippet xmlpatterns/filetree/mainwindow.cpp 1
+
+ The slot function simply calls the private function
+ \c{loadDirectory()} with the path of the chosen directory:
+
+ \target the standard code pattern
+ \snippet xmlpatterns/filetree/mainwindow.cpp 4
+
+ \c{loadDirectory()} demonstrates a standard code pattern for using
+ Qt XML Patterns programatically. First it gets the node model index
+ for the root of the selected directory. Then it creates an instance
+ of QXmlQuery and calls QXmlQuery::bindVariable() to bind the node
+ index to the XQuery variable \c{$fileTree}. It then calls
+ QXmlQuery::setQuery() to load the XQuery text.
+
+ \note QXmlQuery::bindVariable() must be called \e before calling
+ QXmlQuery::setQuery(), which loads and parses the XQuery text and
+ must have access to the variable binding as the text is parsed.
+
+ The next lines create an output device for outputting the query
+ result, which is then used to create a QXmlFormatter to format the
+ query result as XML. QXmlQuery::evaluateTo() is called to run the
+ query, and the formatted XML output is displayed in the left panel
+ of the UI window.
+
+ Finally, the private function \l{Selecting And Running An XQuery}
+ {evaluateResult()} is called to run the currently selected XQuery
+ over the custom node model.
+
+ \note As described in \l{Building And Traversing The Node Model},
+ the \c FileTree class wants to build the custom node model
+ incrementally as it evaluates the XQuery. But, because the
+ \c{loadDirectory()} function runs the \c{wholeTree.xq} XQuery, it
+ actually builds the entire node model anyway. See \l{Node Model
+ Building Strategy} for a discussion about building your custom node
+ model.
+
+ \section3 Selecting And Running An XQuery
+
+ The user chooses an XQuery from the menu in the combobox on the
+ right. Choosing an XQuery signals the
+ \c{on_queryBox_currentIndexChanged()} slot:
+
+ \snippet xmlpatterns/filetree/mainwindow.cpp 2
+
+ The slot function opens and loads the query file and then calls the
+ private function \c{evaluateResult()} to run the query:
+
+ \snippet xmlpatterns/filetree/mainwindow.cpp 3
+
+ \c{evaluateResult()} is a second example of the same code pattern
+ shown in \l{the standard code pattern} {loadDirectory()}. In this
+ case, it runs the XQuery currently selected in the combobox instead
+ of \c{qrc:/queries/wholeTree.xq}, and it outputs the query result to
+ the panel on the lower right of the UI window.
+
+ \section2 Node Model Building Strategy
+
+ We saw that the \l{The Custom Node Model Class: FileTree} {FileTree}
+ tries to build its custom node model incrementally, but we also saw
+ that the \l{the standard code pattern} {MainWindow::loadDirectory()}
+ function in the UI class immediately subverts the incremental build
+ by running the \c{wholeTree.xq} XQuery, which traverses the entire
+ selected directory, thereby causing the entire node model to be
+ built.
+
+ If we want to preserve the incremental build capability of the
+ \c{FileTree} class, we can strip the running of \c{wholeTree.xq} out
+ of \l{the standard code pattern} {MainWindow::loadDirectory()}:
+
+ \snippet xmlpatterns/filetree/mainwindow.cpp 5
+ \snippet xmlpatterns/filetree/mainwindow.cpp 6
+
+ Note, however, that \c{FileTree} doesn't have the capability of
+ deleting all or part of the node model. The node model, once built,
+ is only deleted when the \c{FileTree} instance goes out of scope.
+
+ In this example, each element node in the node model represents a
+ directory or a file in the computer's file system, and each node is
+ represented by an instance of QFileInfo. An instance of QFileInfo is
+ not costly to produce, but you might imagine a node model where
+ building new nodes is very costly. In such cases, the capability to
+ build the node model incrementally is important, because it allows
+ us to only build the region of the model we need for evaluating the
+ query. In other cases, it will be simpler to just build the entire
+ node model.
+
+*/
diff --git a/examples/xmlpatterns/recipes/doc/src/recipes.qdoc b/examples/xmlpatterns/recipes/doc/src/recipes.qdoc
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+/****************************************************************************
+**
+** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:FDL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Free Documentation License Usage
+** Alternatively, this file may be used under the terms of the GNU Free
+** Documentation License version 1.3 as published by the Free Software
+** Foundation and appearing in the file included in the packaging of
+** this file. Please review the following information to ensure
+** the GNU Free Documentation License version 1.3 requirements
+** will be met: http://www.gnu.org/copyleft/fdl.html.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+ \example xmlpatterns/recipes
+ \title Recipes Example
+
+ The Recipes example shows how to use Qt XML Patterns to query XML data
+ loaded from a file.
+
+ \tableofcontents
+
+ \section1 Introduction
+
+ In this case, the XML data represents a cookbook, \c{cookbook.xml},
+ which contains \c{<cookbook>} as its document element, which in turn
+ contains a sequence of \c{<recipe>} elements. This XML data is
+ searched using queries stored in XQuery files (\c{*.xq}).
+
+ \section2 The User Interface
+
+ The UI for this example was created using \l{Qt Designer Manual} {Qt
+ Designer}:
+
+ \image recipes-example.png
+
+ The UI consists of three \l{QGroupBox} {group boxes} arranged
+ vertically. The top one contains a \l{QTextEdit} {text viewer} that
+ displays the XML text from the cookbook file. The middle group box
+ contains a \l{QComboBox} {combo box} for choosing the \l{A Short
+ Path to XQuery} {XQuery} to run and a \l{QTextEdit} {text viewer}
+ for displaying the text of the selected XQuery. The \c{.xq} files in
+ the file list above are shown in the combo box menu. Choosing an
+ XQuery loads, parses, and runs the selected XQuery. The query result
+ is shown in the bottom group box's \l{QTextEdit} {text viewer}.
+
+ \section2 Running your own XQueries
+
+ You can write your own XQuery files and run them in the example
+ program. The file \c{xmlpatterns/recipes/recipes.qrc} is the \l{The
+ Qt Resource System} {resource file} for this example. It is used in
+ \c{main.cpp} (\c{Q_INIT_RESOURCE(recipes);}). It lists the XQuery
+ files (\c{.xq}) that can be selected in the combobox.
+
+ \quotefromfile xmlpatterns/recipes/recipes.qrc
+ \printuntil
+
+ To add your own queries to the example's combobox, store your
+ \c{.xq} files in the \c{examples/xmlpatterns/recipes/files}
+ directory and add them to \c{recipes.qrc} as shown above.
+
+ \section1 Code Walk-Through
+
+ The example's main() function creates the standard instance of
+ QApplication. Then it creates an instance of the UI class, shows it,
+ and starts the Qt event loop:
+
+ \snippet xmlpatterns/recipes/main.cpp 0
+
+ \section2 The UI Class: QueryMainWindow
+
+ The example's UI is a conventional Qt GUI application inheriting
+ QMainWindow and the class generated by \l{Qt Designer Manual} {Qt
+ Designer}:
+
+ \snippet xmlpatterns/recipes/querymainwindow.h 0
+
+ The constructor finds the window's \l{QComboBox} {combo box} child
+ widget and connects its \l{QComboBox::currentIndexChanged()}
+ {currentIndexChanged()} signal to the window's \c{displayQuery()}
+ slot. It then calls \c{loadInputFile()} to load \c{cookbook.xml} and
+ display its contents in the top group box's \l{QTextEdit} {text
+ viewer} . Finally, it finds the XQuery files (\c{.xq}) and adds each
+ one to the \l{QComboBox} {combo box} menu.
+
+ \snippet xmlpatterns/recipes/querymainwindow.cpp 0
+
+ The work is done in the \l{displayQuery() slot} {displayQuery()}
+ slot and the \l{evaluate() function} {evaluate()} function it
+ calls. \l{displayQuery() slot} {displayQuery()} loads and displays
+ the selected query file and passes the XQuery text to \l{evaluate()
+ function} {evaluate()}.
+
+ \target displayQuery() slot
+ \snippet xmlpatterns/recipes/querymainwindow.cpp 1
+
+ \l{evaluate() function} {evaluate()} demonstrates the standard
+ Qt XML Patterns usage pattern. First, an instance of QXmlQuery is
+ created (\c{query}). The \c{query's} \l{QXmlQuery::bindVariable()}
+ {bindVariable()} function is then called to bind the \c cookbook.xml
+ file to the XQuery variable \c inputDocument. \e{After} the variable
+ is bound, \l{QXmlQuery::setQuery()} {setQuery()} is called to pass
+ the XQuery text to the \c query.
+
+ \note \l{QXmlQuery::setQuery()} {setQuery()} must be called
+ \e{after} \l{QXmlQuery::bindVariable()} {bindVariable()}.
+
+ Passing the XQuery to \l{QXmlQuery::setQuery()} {setQuery()} causes
+ Qt XML Patterns to parse the XQuery. \l{QXmlQuery::isValid()} is
+ called to ensure that the XQuery was correctly parsed.
+
+ \target evaluate() function
+ \snippet xmlpatterns/recipes/querymainwindow.cpp 2
+
+ If the XQuery is valid, an instance of QXmlFormatter is created to
+ format the query result as XML into a QBuffer. To evaluate the
+ XQuery, an overload of \l{QXmlQuery::evaluateTo()} {evaluateTo()} is
+ called that takes a QAbstractXmlReceiver for its output
+ (QXmlFormatter inherits QAbstractXmlReceiver). Finally, the
+ formatted XML result is displayed in the UI's bottom text view.
+
+ \note Each XQuery \c{.xq} file must declare the \c{$inputDocument}
+ variable to represent the \c cookbook.xml document:
+
+ \code
+ (: All ingredients for Mushroom Soup. :)
+ declare variable $inputDocument external;
+
+ doc($inputDocument)/cookbook/recipe[@xml:id = "MushroomSoup"]/ingredient/
+ <p>{@name, @quantity}</p>
+ \endcode
+
+ \note If you add add your own query.xq files, you must declare the
+ \c{$inputDocument} and use it as shown above.
+
+*/
diff --git a/examples/xmlpatterns/schema/doc/src/schema.qdoc b/examples/xmlpatterns/schema/doc/src/schema.qdoc
new file mode 100644
index 0000000..0dc3a91
--- /dev/null
+++ b/examples/xmlpatterns/schema/doc/src/schema.qdoc
@@ -0,0 +1,129 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:FDL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Free Documentation License Usage
+** Alternatively, this file may be used under the terms of the GNU Free
+** Documentation License version 1.3 as published by the Free Software
+** Foundation and appearing in the file included in the packaging of
+** this file. Please review the following information to ensure
+** the GNU Free Documentation License version 1.3 requirements
+** will be met: http://www.gnu.org/copyleft/fdl.html.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+ \example xmlpatterns/schema
+ \title XML Schema Validation Example
+
+ The XML Schema Validation example shows how to use Qt XML Patterns to
+ validate XML with a W3C XML Schema.
+
+ \tableofcontents
+
+ \section1 Introduction
+
+ The example application shows different XML schema definitions and
+ for every definition two XML instance documents, one that is valid
+ according to the schema and one that is not.
+ The user can select the valid or invalid instance document, change
+ it and validate it again.
+
+ \section2 The User Interface
+
+ The UI for this example was created using \l{Qt Designer Manual} {Qt
+ Designer}:
+
+ \image schema-example.png
+
+ The UI consists of three parts, at the top the XML schema \l{QComboBox} {selection}
+ and the schema \l{QTextBrowser} {viewer}, below the XML instance \l{QComboBox} {selection}
+ and the instance \l{QTextEdit} {editor} and at the bottom the validation status \l{QLabel} {label}
+ next to the validation \l{QPushButton} {button}.
+
+ \section2 Validating XML Instance Documents
+
+ You can select one of the three predefined XML schemas and for each schema
+ an valid or invalid instance document. A click on the 'Validate' button will
+ validate the content of the XML instance editor against the schema from the
+ XML schema viewer. As you can modify the content of the instance editor, different
+ instances can be tested and validation error messages analysed.
+
+ \section1 Code Walk-Through
+
+ The example's main() function creates the standard instance of
+ QApplication. Then it creates an instance of the mainwindow class, shows it,
+ and starts the Qt event loop:
+
+ \snippet xmlpatterns/schema/main.cpp 0
+
+ \section2 The UI Class: MainWindow
+
+ The example's UI is a conventional Qt GUI application inheriting
+ QMainWindow and the class generated by \l{Qt Designer Manual} {Qt
+ Designer}:
+
+ \snippet xmlpatterns/schema/mainwindow.h 0
+
+ The constructor fills the schema and instance \l{QComboBox} selections with the predefined
+ schemas and instances and connects their \l{QComboBox::currentIndexChanged()} {currentIndexChanged()}
+ signals to the window's \c{schemaSelected()} resp. \c{instanceSelected()} slot.
+ Furthermore the signal-slot connections for the validation \l{QPushButton} {button}
+ and the instance \l{QTextEdit} {editor} are set up.
+
+ The call to \c{schemaSelected(0)} and \c{instanceSelected(0)} will trigger the validation
+ of the initial Contact Schema example.
+
+ \snippet xmlpatterns/schema/mainwindow.cpp 0
+
+ In the \c{schemaSelected()} slot the content of the instance \l{QComboBox} {selection}
+ is adapted to the selected schema and the corresponding schema is loaded from the
+ \l{The Qt Resource System} {resource file} and displayed in the schema \l{QTextBrowser} {viewer}.
+ At the end of the method a revalidation is triggered.
+
+ \snippet xmlpatterns/schema/mainwindow.cpp 1
+
+ In the \c{instanceSelected()} slot the selected instance is loaded from the
+ \l{The Qt Resource System} {resource file} and loaded into the instance \l{QTextEdit} {editor}
+ an the revalidation is triggered again.
+
+ \snippet xmlpatterns/schema/mainwindow.cpp 2
+
+ The \c{validate()} slot does the actual work in this example.
+ At first it stores the content of the schema \l{QTextBrowser} {viewer} and the
+ \l{QTextEdit} {editor} into temporary \l{QByteArray} {variables}.
+ Then it instanciates a \c{MessageHandler} object which inherits from
+ \l{QAbstractMessageHandler} {QAbstractMessageHandler} and is a convenience
+ class to store error messages from the XmlPatterns system.
+
+ \snippet xmlpatterns/schema/mainwindow.cpp 4
+
+ After the \l{QXmlSchema} {QXmlSchema} is instanciated and the message handler set
+ on it, the \l{QXmlSchema::load()} {load()} method is called with the schema data as argument.
+ If the schema is invalid or a parsing error has occured, \l{QXmlSchema::isValid()} {isValid()}
+ returns \c{false} and the error is flagged in \c{errorOccurred}.
+ If the loading was successful, a \l{QXmlSchemaValidator} {QXmlSchemaValidator} is
+ instanciated and the schema passed in the constructor.
+ A call to \l{QXmlSchemaValidator::validate()} {validate()} will validate the passed
+ XML instance data against the XML schema. The return value of that method signals
+ whether the validation was successful.
+ Depending on the success the status \l{QLabel} {label} is set to 'validation successful'
+ or the error message stored in the \c{MessageHandler}
+
+ The rest of the code does only some fancy coloring and eyecandy.
+
+ \snippet xmlpatterns/schema/mainwindow.cpp 3
+*/
diff --git a/examples/xmlpatterns/trafficinfo/doc/src/trafficinfo.qdoc b/examples/xmlpatterns/trafficinfo/doc/src/trafficinfo.qdoc
new file mode 100644
index 0000000..7a8b7e8
--- /dev/null
+++ b/examples/xmlpatterns/trafficinfo/doc/src/trafficinfo.qdoc
@@ -0,0 +1,149 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:FDL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Free Documentation License Usage
+** Alternatively, this file may be used under the terms of the GNU Free
+** Documentation License version 1.3 as published by the Free Software
+** Foundation and appearing in the file included in the packaging of
+** this file. Please review the following information to ensure
+** the GNU Free Documentation License version 1.3 requirements
+** will be met: http://www.gnu.org/copyleft/fdl.html.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+ \example xmlpatterns/trafficinfo
+ \title TrafficInfo Example
+
+ Shows how XQuery can be used extract information from WML documents provided by a WAP service.
+
+ \section1 Overview
+
+ The WAP service used in this example is \l{Trafikanten}{wap.trafikanten.no}
+ that is run by the Norwegian governmental agency for public transport in
+ Oslo. The service provides real time information about the departure of
+ busses, trams and undergrounds for every station in the city area.
+
+ This example application displays the departure information for a specific
+ station and provides the feature to filter for a special bus or tram line.
+
+ \image trafficinfo-example.png
+
+ \section1 Retrieving the Data
+
+ Without the knowledge of XQuery, one would use QNetworkAccessManager to
+ query the WML document from the WAP service and then using the QDom
+ classes or QXmlStreamReader classes to iterate over the document and
+ extract the needed information.
+ However this approach results in a lot of glue code and consumes valuable
+ developer time, so we are looking for something that can access XML
+ documents locally or over the network and extract data according to given
+ filter rules. That's the point where XQuery enters the stage!
+
+ If we want to know when the underground number 6 in direction
+ \Aring\c{}sjordet is passing the underground station in Nydalen on November
+ 14th 2008 after 1pm, we use the following URL:
+
+ \c{http://wap.trafikanten.no/F.asp?f=03012130&t=13&m=00&d=14.11.2008&start=1}
+
+ The parameters have the following meanings:
+ \list
+ \li \e{f} The unique station ID of Nydalen.
+ \li \e{t} The hour in 0-23 format.
+ \li \e{m} The minute in 0-59 format.
+ \li \e{d} The date in dd.mm.yyyy format.
+ \li \e{start} Not interesting for our use but should be passed.
+ \endlist
+
+ As a result we get the following document:
+
+ \quotefile xmlpatterns/trafficinfo/time_example.wml
+
+ So for every departure we have a \c <a> tag that contains the time as a
+ text element, and the following text element contains the line number
+ and direction.
+
+ To encapsulate the XQuery code in the example application, we create a
+ custom \c TimeQuery class. This provides the \c queryInternal() function
+ that takes a station ID and date/time as input and returns the list of
+ times and directions:
+
+ \snippet xmlpatterns/trafficinfo/timequery.cpp 1
+
+ The first lines of this function synthesize the XQuery strings that fetch
+ the document and extract the data.
+ For better readability, two separated queries are used here: the first one
+ fetches the times and the second fetches the line numbers and directions.
+
+ The \c doc() XQuery method opens a local or remote XML document and returns
+ it, so the \c{/wml/card/p/small/} statement behind it selects all XML nodes
+ that can be reached by the path, \c wml \rarrow \c card \rarrow \c p \rarrow
+ \c small.
+ Now we are on the node that contains all the XML nodes we are interested in.
+
+ In the first query we select all \c a nodes that have a \c href attribute
+ starting with the string "Rute" and return the text of these nodes.
+
+ In the second query we select all text nodes that are children of the
+ \c small node which start with a number.
+ These two queries are passed to the QXmlQuery instance and are evaluated
+ to string lists. After some sanity checking, we have collected all the
+ information we need.
+
+ In the section above we have seen that an unique station ID must be passed
+ as an argument to the URL for retrieving the time, so how to find out which
+ is the right station ID to use? The WAP service provides a page for that
+ as well, so the URL
+
+ \c{http://wap.trafikanten.no/FromLink1.asp?fra=Nydalen}
+
+ will return the following document:
+
+ \snippet xmlpatterns/trafficinfo/station_example.wml 0
+
+ The names of the available stations are listed as separate text elements
+ and the station ID is part of the \c href attribute of the parent \c a
+ (anchor) element. In our example, the \c StationQuery class encapsulates
+ the action of querying the stations that match the given name pattern with
+ the following code:
+
+ \snippet xmlpatterns/trafficinfo/stationquery.cpp 0
+
+ Just as in the \c TimeQuery implementation, the first step is to
+ synthesize the XQuery strings for selecting the station names and the
+ station IDs. As the station name that we pass in the URL will be input
+ from the user, we should protect the XQuery from code injection by using
+ the QXmlQuery::bindVariable() method to do proper quoting of the variable
+ content for us instead of concatenating the two strings manually.
+
+ So, we define a XQuery \c $station variable that is bound to the user
+ input. This variable is concatenated inside the XQuery code with the
+ \c concat method. To extract the station IDs, we select all \c a elements
+ that have an \c title attribute with the content "Velg", and from these
+ elements we take the substring of the \c href attribute that starts at the
+ 18th character.
+
+ The station name can be extracted a bit more easily by just taking the
+ text elements of the selected \a elements.
+
+ After some sanity checks we have all the station IDs and the corresponding
+ names available.
+
+ The rest of the code in this example is just for representing the time and
+ station information to the user, and uses techniques described in the
+ \l{Widget Examples}.
+*/
diff --git a/examples/xmlpatterns/xquery/doc/src/globalVariables.qdoc b/examples/xmlpatterns/xquery/doc/src/globalVariables.qdoc
new file mode 100644
index 0000000..08133f6
--- /dev/null
+++ b/examples/xmlpatterns/xquery/doc/src/globalVariables.qdoc
@@ -0,0 +1,201 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:FDL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Free Documentation License Usage
+** Alternatively, this file may be used under the terms of the GNU Free
+** Documentation License version 1.3 as published by the Free Software
+** Foundation and appearing in the file included in the packaging of
+** this file. Please review the following information to ensure
+** the GNU Free Documentation License version 1.3 requirements
+** will be met: http://www.gnu.org/copyleft/fdl.html.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+ \example xmlpatterns/xquery/globalVariables
+ \title C++ Source Code Analyzer Example
+
+ This example uses XQuery and the \c xmlpatterns command line utility to
+ query C++ source code.
+
+ \tableofcontents
+
+ \section1 Introduction
+
+ Suppose we want to analyze C++ source code to find coding standard
+ violations and instances of bad or inefficient patterns. We can do
+ it using the common searching and pattern matching utilities to
+ process the C++ files (e.g., \c{grep}, \c{sed}, and \c{awk}). Now
+ we can also use XQuery with the Qt XML Patterns module.
+
+ An extension to the \c{g++} open source C++ compiler
+ (\l{http://public.kitware.com/GCC_XML/HTML/Index.html} {GCC-XML})
+ generates an XML description of C++ source code declarations. This
+ XML description can then be processed by Qt XML Patterns using
+ XQueries to navigate the XML description of the C++ source and
+ produce a report. Consider the problem of finding mutable global
+ variables:
+
+ \section2 Reporting Uses of Mutable Global Variables
+
+ Suppose we want to introduce threading to a C++ application that
+ was originally written without threading. In a threaded program,
+ mutable global variables can cause bugs, because one thread might
+ change a global variable that other threads are reading, or two
+ threads might try to set the same global variable. So when
+ converting our program to use threading, one of the things we must
+ do is protect the global variables to prevent the bugs described
+ above. How can we use XQuery and
+ \l{http://public.kitware.com/GCC_XML/HTML/Index.html} {GCC-XML} to
+ find the variables that need protecting?
+
+ \section3 A C++ application
+
+ Consider the declarations in this hypothetical C++ application:
+
+ \snippet xmlpatterns/xquery/globalVariables/globals.cpp 0
+
+ \section3 The XML description of the C++ application
+
+ Submitting this C++ source to
+ \l{http://public.kitware.com/GCC_XML/HTML/Index.html} {GCC-XML}
+ produces this XML description:
+
+ \quotefromfile xmlpatterns/xquery/globalVariables/globals.gccxml
+ \printuntil
+
+ \section3 The XQuery for finding global variables
+
+ We need an XQuery to find the global variables in the XML
+ description. Here is our XQuery source. We walk through it in
+ \l{XQuery Code Walk-Through}.
+
+ \quotefromfile xmlpatterns/xquery/globalVariables/reportGlobals.xq
+ \printuntil
+
+ \section3 Running the XQuery
+
+ To run the XQuery using the \c xmlpatterns command line utility,
+ enter the following command:
+
+ \code
+ xmlpatterns reportGlobals.xq -param fileToOpen=globals.gccxml -output globals.html
+ \endcode
+
+ \section3 The XQuery output
+
+ The \c xmlpatterns command loads and parses \c globals.gccxml,
+ runs the XQuery \c reportGlobals.xq, and generates this report:
+
+ \div {class="details"}
+ Start report: 2008-12-16T13:43:49.65Z
+ \enddiv
+
+ Global variables with complex types:
+ \list 1
+ \li \span {class="variableName"} {mutableComplex1} in globals.cpp at line 14
+ \li \span {class="variableName"} {mutableComplex2} in globals.cpp at line 15
+ \li \span {class="variableName"} {constComplex1} in globals.cpp at line 16
+ \li \span {class="variableName"} {constComplex2} in globals.cpp at line 17
+ \endlist
+
+ Mutable global variables with primitives types:
+ \list 1
+ \li \span {class="variableName"} {mutablePrimitive1} in globals.cpp at line 1
+ \li \span {class="variableName"} {mutablePrimitive2} in globals.cpp at line 2
+ \endlist
+
+ \div {class="details"} End report: 2008-12-16T13:43:49.65Z \enddiv
+
+ \section1 XQuery Code Walk-Through
+
+ The XQuery source is in
+ \c{examples/xmlpatterns/xquery/globalVariables/reportGlobals.xq}
+ It begins with two variable declarations that begin the XQuery:
+
+ \quotefromfile xmlpatterns/xquery/globalVariables/reportGlobals.xq
+ \skipto declare variable
+ \printto (:
+
+ The first variable, \c{$fileToOpen}, appears in the \c xmlpatterns
+ command shown earlier, as \c{-param fileToOpen=globals.gccxml}.
+ This binds the variable name to the file name. This variable is
+ then used in the declaration of the second variable, \c{$inDoc},
+ as the parameter to the
+ \l{http://www.w3.org/TR/xpath-functions/#func-doc} {doc()}
+ function. The \c{doc()} function returns the document node of
+ \c{globals.gccxml}, which is assigned to \c{$inDoc} to be used
+ later in the XQuery as the root node of our searches for global
+ variables.
+
+ Next skip to the end of the XQuery, where the \c{<html>} element
+ is constructed. The \c{<html>} will contain a \c{<head>} element
+ to specify a heading for the html page, followed by some style
+ instructions for displaying the text, and then the \c{<body>}
+ element.
+
+ \quotefromfile xmlpatterns/xquery/globalVariables/reportGlobals.xq
+ \skipto <html xmlns
+ \printuntil
+
+ The \c{<body>} element contains a call to the \c{local:report()}
+ function, which is where the query does the "heavy lifting." Note
+ the two \c{return} clauses separated by the \e {comma operator}
+ about halfway down:
+
+ \quotefromfile xmlpatterns/xquery/globalVariables/reportGlobals.xq
+ \skipto declare function local:report()
+ \printuntil };
+
+ The \c{return} clauses are like two separate queries. The comma
+ operator separating them means that both \c{return} clauses are
+ executed and both return their results, or, rather, both output
+ their results. The first \c{return} clause searches for global
+ variables with complex types, and the second searches for mutable
+ global variables with primitive types.
+
+ Here is the html generated for the \c{<body>} element. Compare
+ it with the XQuery code above:
+
+ \quotefromfile xmlpatterns/xquery/globalVariables/globals.html
+ \skipto <body>
+ \printuntil </body>
+
+ The XQuery declares three more local functions that are called in
+ turn by the \c{local:report()} function. \c{isComplexType()}
+ returns true if the variable has a complex type. The variable can
+ be mutable or const.
+
+ \quotefromfile xmlpatterns/xquery/globalVariables/reportGlobals.xq
+ \skipto declare function local:isComplexType
+ \printuntil };
+
+ \c{isPrimitive()} returns true if the variable has a primitive
+ type. The variable must be mutable.
+
+ \quotefromfile xmlpatterns/xquery/globalVariables/reportGlobals.xq
+ \skipto declare function local:isPrimitive
+ \printuntil };
+
+ \c{location()} returns a text constructed from the variable's file
+ and line number attributes.
+
+ \quotefromfile xmlpatterns/xquery/globalVariables/reportGlobals.xq
+ \skipto declare function local:location
+ \printuntil };
+
+ */