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authorJ-P Nurmi <jpnurmi@digia.com>2012-11-27 14:18:41 +0100
committerThe Qt Project <gerrit-noreply@qt-project.org>2012-11-28 00:56:34 +0100
commitcb961007c534b260b779ed513d33843a9dce01f4 (patch)
treed780db451451d51ab10aa114a6e01f813e32c852 /examples/widgets/doc
parent3d66b86cb7407201f091d16130b3da73e613cc5f (diff)
Examples: move widgets specific "tools" examples to the correct place
examples/tools -> examples/widgets/tools Change-Id: I8b9e23c45e07ce5cd9da8f24a9a9f7ae10b2b107 Reviewed-by: hjk <qthjk@ovi.com>
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-rw-r--r--examples/widgets/doc/src/completer.qdoc249
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-rw-r--r--examples/widgets/doc/src/i18n.qdoc37
-rw-r--r--examples/widgets/doc/src/plugandpaint.qdoc540
-rw-r--r--examples/widgets/doc/src/regexp.qdoc37
-rw-r--r--examples/widgets/doc/src/settingseditor.qdoc37
-rw-r--r--examples/widgets/doc/src/styleplugin.qdoc137
-rw-r--r--examples/widgets/doc/src/treemodelcompleter.qdoc171
-rw-r--r--examples/widgets/doc/src/undo.qdoc43
-rw-r--r--examples/widgets/doc/src/undoframework.qdoc291
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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 tools/completer
+ \title Completer Example
+
+ The Completer example shows how to provide string-completion facilities
+ for an input widget based on data provided by a model.
+
+ \image completer-example.png
+
+ This example uses a custom item model, \c FileSystemModel, and a QCompleter object.
+ QCompleter is a class that provides completions based on an item model. The
+ type of model, the completion mode, and the case sensitivity can be
+ selected using combo boxes.
+
+ \section1 The Resource File
+
+ The Completer example requires a resource file in order to store the
+ \e{countries.txt} and \e{words.txt}. The resource file contains the
+ following code:
+
+ \quotefile tools/completer/completer.qrc
+
+ \section1 FileSystemModel Class Definition
+
+ The \c FileSystemModel class is a subclass of QFileSystemModel, which provides a data
+ model for the local filesystem.
+
+ \snippet tools/completer/fsmodel.h 0
+
+ This class only has a constructor and a \c data() function as it is only
+ created to enable \c data() to return the entire file path for the
+ display role, unlike \l{QFileSystemModel}'s \c data() function that only returns
+ the folder and not the drive label. This is further explained in
+ \c FileSystemModel's implementation.
+
+ \section1 FileSystemModel Class Implementation
+
+ The constructor for the \c FileSystemModel class is used to pass \a parent to
+ QFileSystemModel.
+
+ \snippet tools/completer/fsmodel.cpp 0
+
+ As mentioned earlier, the \c data() function is reimplemented in order to
+ get it to return the entire file parth for the display role. For example,
+ with a QFileSystemModel, you will see "Program Files" in the view. However, with
+ \c FileSystemModel, you will see "C:\\Program Files".
+
+ \snippet tools/completer/fsmodel.cpp 1
+
+ The screenshots below illustrate this difference:
+
+ \table
+ \row \li \inlineimage completer-example-qdirmodel.png
+ \li \inlineimage completer-example-dirmodel.png
+ \endtable
+
+ The Qt::EditRole, which QCompleter uses to look for matches, is left
+ unchanged.
+
+ \section1 MainWindow Class Definition
+
+ The \c MainWindow class is a subclass of QMainWindow and implements five
+ private slots - \c about(), \c changeCase(), \c changeMode(), \c changeModel(),
+ and \c changeMaxVisible().
+
+ \snippet tools/completer/mainwindow.h 0
+
+ Within the \c MainWindow class, we have two private functions:
+ \c createMenu() and \c modelFromFile(). We also declare the private widgets
+ needed - three QComboBox objects, a QCheckBox, a QCompleter, a QLabel, and
+ a QLineEdit.
+
+ \snippet tools/completer/mainwindow.h 1
+
+ \section1 MainWindow Class Implementation
+
+ The constructor of \c MainWindow constructs a \c MainWindow with a parent
+ widget and initializes the private members. The \c createMenu() function
+ is then invoked.
+
+ We set up three QComboBox objects, \c modelComb, \c modeCombo and
+ \c caseCombo. By default, the \c modelCombo is set to QFileSystemModel,
+ the \c modeCombo is set to "Filtered Popup" and the \c caseCombo is set
+ to "Case Insensitive".
+
+ \snippet tools/completer/mainwindow.cpp 0
+
+ The \c maxVisibleSpinBox is created and determines the number of visible
+ item in the completer
+
+ The \c wrapCheckBox is then set up. This \c checkBox determines if the
+ \c{completer}'s \l{QCompleter::setWrapAround()}{setWrapAround()} property
+ is enabled or disabled.
+
+ \snippet tools/completer/mainwindow.cpp 1
+
+ We instantiate \c contentsLabel and set its size policy to
+ \l{QSizePolicy::Fixed}{fixed}. The combo boxes' \l{QComboBox::activated()}
+ {activated()} signals are then connected to their respective slots.
+
+ \snippet tools/completer/mainwindow.cpp 2
+
+ The \c lineEdit is set up and then we arrange all the widgets using a
+ QGridLayout. The \c changeModel() function is called, to initialize the
+ \c completer.
+
+ \snippet tools/completer/mainwindow.cpp 3
+
+ The \c createMenu() function is used to instantiate the QAction objects
+ needed to fill the \c fileMenu and \c helpMenu. The actions'
+ \l{QAction::triggered()}{triggered()} signals are connected to their
+ respective slots.
+
+ \snippet tools/completer/mainwindow.cpp 4
+
+ The \c modelFromFile() function accepts the \a fileName of a file and
+ processes it depending on its contents.
+
+ We first validate the \c file to ensure that it can be opened in
+ QFile::ReadOnly mode. If this is unsuccessful, the function returns an
+ empty QStringListModel.
+
+ \snippet tools/completer/mainwindow.cpp 5
+
+ The mouse cursor is then overridden with Qt::WaitCursor before we fill
+ a QStringList object, \c words, with the contents of \c file. Once this
+ is done, we restore the mouse cursor.
+
+ \snippet tools/completer/mainwindow.cpp 6
+
+ As mentioned earlier, the resources file contains two files -
+ \e{countries.txt} and \e{words.txt}. If the \c file read is \e{words.txt},
+ we return a QStringListModel with \c words as its QStringList and
+ \c completer as its parent.
+
+ \snippet tools/completer/mainwindow.cpp 7
+
+ If the \c file read is \e{countries.txt}, then we require a
+ QStandardItemModel with \c words.count() rows, 2 columns, and \c completer
+ as its parent.
+
+ \snippet tools/completer/mainwindow.cpp 8
+
+ A standard line in \e{countries.txt} is:
+ \quotation
+ Norway NO
+ \endquotation
+
+ Hence, to populate the QStandardItemModel object, \c m, we have to
+ split the country name and its symbol. Once this is done, we return
+ \c m.
+
+ \snippet tools/completer/mainwindow.cpp 9
+
+ The \c changeMode() function sets the \c{completer}'s mode, depending on
+ the value of \c index.
+
+ \snippet tools/completer/mainwindow.cpp 10
+
+ The \c changeModel() function changes the item model used based on the
+ model selected by the user.
+
+ A \c switch statement is used to change the item model based on the index
+ of \c modelCombo. If \c case is 0, we use an unsorted QFileSystemModel, providing
+ us with a file path excluding the drive label.
+
+ \snippet tools/completer/mainwindow.cpp 11
+
+ Note that we create the model with \c completer as the parent as this
+ allows us to replace the model with a new model. The \c completer will
+ ensure that the old one is deleted the moment a new model is assigned
+ to it.
+
+ If \c case is 1, we use the \c DirModel we defined earlier, resulting in
+ full paths for the files.
+
+ \snippet tools/completer/mainwindow.cpp 12
+
+ When \c case is 2, we attempt to complete names of countries. This requires
+ a QTreeView object, \c treeView. The country names are extracted from
+ \e{countries.txt} and set the popup used to display completions to
+ \c treeView.
+
+ \snippet tools/completer/mainwindow.cpp 13
+
+ The screenshot below shows the Completer with the country list model.
+
+ \image completer-example-country.png
+
+ If \c case is 3, we attempt to complete words. This is done using a
+ QStringListModel that contains data extracted from \e{words.txt}. The
+ model is sorted \l{QCompleter::CaseInsensitivelySortedModel}
+ {case insensitively}.
+
+ The screenshot below shows the Completer with the word list model.
+
+ \image completer-example-word.png
+
+ Once the model type is selected, we call the \c changeMode() function and
+ the \c changeCase() function and set the wrap option accordingly. The
+ \c{wrapCheckBox}'s \l{QCheckBox::clicked()}{clicked()} signal is connected
+ to the \c{completer}'s \l{QCompleter::setWrapAround()}{setWrapAround()}
+ slot.
+
+ \snippet tools/completer/mainwindow.cpp 14
+
+ The \c changeMaxVisible() update the maximum number of visible items in
+ the completer.
+
+ \snippet tools/completer/mainwindow.cpp 15
+
+ The \c about() function provides a brief description about the example.
+
+ \snippet tools/completer/mainwindow.cpp 16
+
+ \section1 \c main() Function
+
+ The \c main() function instantiates QApplication and \c MainWindow and
+ invokes the \l{QWidget::show()}{show()} function.
+
+ \snippet tools/completer/main.cpp 0
+ */
diff --git a/examples/widgets/doc/src/echoplugin.qdoc b/examples/widgets/doc/src/echoplugin.qdoc
new file mode 100644
index 0000000000..81ba18cdff
--- /dev/null
+++ b/examples/widgets/doc/src/echoplugin.qdoc
@@ -0,0 +1,208 @@
+/****************************************************************************
+**
+** 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 tools/echoplugin
+ \title Echo Plugin Example
+
+ This example shows how to create a Qt plugin.
+
+ \image echopluginexample.png
+
+ There are two kinds of plugins in Qt: plugins that extend Qt
+ itself and plugins that extend applications written in Qt. In this
+ example, we show the procedure of implementing plugins that extend
+ applications. When you create a plugin you declare an interface,
+ which is a class with only pure virtual functions. This interface
+ is inherited by the class that implements the plugin. The class is
+ stored in a shared library and can therefore be loaded by
+ applications at run-time. When loaded, the plugin is dynamically
+ cast to the interface using Qt's \l{Meta-Object
+ System}{meta-object system}. The plugin \l{How to Create Qt
+ Plugins}{overview document} gives a high-level introduction to
+ plugins.
+
+ We have implemented a plugin, the \c EchoPlugin, which implements
+ the \c EchoInterface. The interface consists of \c echo(), which
+ takes a QString as argument. The \c EchoPlugin returns the string
+ unaltered (i.e., it works as the familiar echo command found in
+ both Unix and Windows).
+
+ We test the plugin in \c EchoWindow: when you push the QPushButton
+ (as seen in the image above), the application sends the text in
+ the QLineEdit to the plugin, which echoes it back to the
+ application. The answer from the plugin is displayed in the
+ QLabel.
+
+
+ \section1 EchoWindow Class Definition
+
+ The \c EchoWindow class lets us test the \c EchoPlugin through a
+ GUI.
+
+ \snippet tools/echoplugin/echowindow/echowindow.h 0
+
+ We load the plugin in \c loadPlugin() and cast it to \c
+ EchoInterface. When the user clicks the \c button we take the
+ text in \c lineEdit and call the interface's \c echo() with it.
+
+
+ \section1 EchoWindow Class Implementation
+
+ We start with a look at the constructor:
+
+ \snippet tools/echoplugin/echowindow/echowindow.cpp 0
+
+ We create the widgets and set a title for the window. We then load
+ the plugin. \c loadPlugin() returns false if the plugin could not
+ be loaded, in which case we disable the widgets. If you wish a
+ more detailed error message, you can use
+ \l{QPluginLoader::}{errorString()}; we will look more closely at
+ QPluginLoader later.
+
+ Here is the implementation of \c sendEcho():
+
+ \snippet tools/echoplugin/echowindow/echowindow.cpp 1
+
+ This slot is called when the user pushes \c button or presses
+ enter in \c lineEdit. We call \c echo() of the echo interface. In
+ our example this is the \c EchoPlugin, but it could be any plugin
+ that inherit the \c EchoInterface. We take the QString returned
+ from \c echo() and display it in the \c label.
+
+ Here is the implementation of \c createGUI():
+
+ \snippet tools/echoplugin/echowindow/echowindow.cpp 2
+
+ We create the widgets and lay them out in a grid layout. We
+ connect the label and line edit to our \c sendEcho() slot.
+
+ Here is the \c loadPlugin() function:
+
+ \snippet tools/echoplugin/echowindow/echowindow.cpp 3
+
+ Access to plugins at run-time is provided by QPluginLoader. You
+ supply it with the filename of the shared library the plugin is
+ stored in and call \l{QPluginLoader::}{instance()}, which loads
+ and returns the root component of the plugin (i.e., it resolves
+ the type of the plugin and creates a QObject instance of it). If
+ the plugin was not successfully loaded, it will be null, so we
+ return false. If it was loaded correctly, we can cast the plugin
+ to our \c EchoInterface and return true. In the case that the
+ plugin loaded does not implement the \c EchoInterface, \c
+ instance() will return null, but this cannot happen in our
+ example. Notice that the location of the plugin is not the same
+ for all platforms.
+
+
+ \section1 EchoInterface Class Definition
+
+ The \c EchoInterface defines the functions that the plugin will
+ provide. An interface is a class that only consists of pure
+ virtual functions. If non virtual functions were present in the
+ class you would get misleading compile errors in the moc files.
+
+ \snippet tools/echoplugin/echowindow/echointerface.h 0
+
+ We declare \c echo(). In our \c EchoPlugin we use this method to
+ return, or echo, \a message.
+
+ We use the Q_DECLARE_INTERFACE macro to let \l{Meta-Object
+ System}{Qt's meta object system} aware of the interface. We do
+ this so that it will be possible to identify plugins that
+ implements the interface at run-time. The second argument is a
+ string that must identify the interface in a unique way.
+
+
+ \section1 EchoPlugin Class Definition
+
+ We inherit both QObject and \c EchoInterface to make this class a
+ plugin. The Q_INTERFACES macro tells Qt which interfaces the class
+ implements. In our case we only implement the \c EchoInterface.
+ If a class implements more than one interface, they are given as
+ a comma separated list.
+
+ \snippet tools/echoplugin/plugin/echoplugin.h 0
+
+
+ \section1 EchoPlugin Class Implementation
+
+ Here is the implementation of \c echo():
+
+ \snippet tools/echoplugin/plugin/echoplugin.cpp 0
+
+ We simply return the functions parameter.
+
+ \snippet tools/echoplugin/plugin/echoplugin.cpp 1
+
+ We use the Q_EXPORT_PLUGIN2 macro to let Qt know that the \c
+ EchoPlugin class is a plugin. The first parameter is the name of
+ the plugin; it is usual to give the plugin and the library file it
+ is stored in the same name.
+
+ \section1 The \c main() function
+
+ \snippet tools/echoplugin/echowindow/main.cpp 0
+
+ We create an \c EchoWindow and display it as a top-level window.
+
+ \section1 The Profiles
+
+ When creating plugins the profiles need to be adjusted.
+ We show here what changes need to be done.
+
+ The profile in the echoplugin directory uses the \c subdirs
+ template and simply includes includes to directories in which
+ the echo window and echo plugin lives:
+
+ \snippet tools/echoplugin/echoplugin.pro 0
+
+ The profile for the echo window does not need any plugin specific
+ settings. We move on to the plugin profile:
+
+ \snippet tools/echoplugin/plugin/plugin.pro 0
+
+ We need to set the TEMPLATE as we now want to make a library
+ instead of an executable. We also need to tell qmake that we are
+ creating a plugin. The \c EchoInterface that the plugin implements
+ lives in the \c echowindow directory, so we need to add that
+ directory to the include path. We set the TARGET of the project,
+ which is the name of the library file in which the plugin will be
+ stored; qmake appends the appropriate file extension depending on
+ the platform. By convention the target should have the same name
+ as the plugin (set with Q_EXPORT_PLUGIN2)
+
+ \section1 Further reading and examples
+
+ You can find an overview of the macros needed to create plugins
+ \l{Macros for Defining Plugins}{here}.
+
+ We give an example of a plugin that extend Qt in the \l{Style
+ Plugin Example}{style plugin} example. The \l{Plug & Paint
+ Example}{plug and paint} example shows how to create static
+ plugins.
+*/
diff --git a/examples/widgets/doc/src/i18n.qdoc b/examples/widgets/doc/src/i18n.qdoc
new file mode 100644
index 0000000000..980319233d
--- /dev/null
+++ b/examples/widgets/doc/src/i18n.qdoc
@@ -0,0 +1,37 @@
+/****************************************************************************
+**
+** 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 tools/i18n
+ \title I18N Example
+
+ The Internationalization (I18N) example demonstrates Qt's support for translated
+ text. Developers can write the initial application text in one language, and
+ translations can be provided later without any modifications to the code.
+
+ \image i18n-example.png
+*/
diff --git a/examples/widgets/doc/src/plugandpaint.qdoc b/examples/widgets/doc/src/plugandpaint.qdoc
new file mode 100644
index 0000000000..24fb4ab1b9
--- /dev/null
+++ b/examples/widgets/doc/src/plugandpaint.qdoc
@@ -0,0 +1,540 @@
+/****************************************************************************
+**
+** 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 tools/plugandpaint
+ \title Plug & Paint Example
+
+ The Plug & Paint example demonstrates how to write Qt
+ applications that can be extended through plugins.
+
+ \image plugandpaint.png Screenshot of the Plug & Paint example
+
+ A plugin is a dynamic library that can be loaded at run-time to
+ extend an application. Qt makes it possible to create custom
+ plugins and to load them using QPluginLoader. To ensure that
+ plugins don't get lost, it is also possible to link them
+ statically to the executable. The Plug & Paint example uses
+ plugins to support custom brushes, shapes, and image filters. A
+ single plugin can provide multiple brushes, shapes, and/or
+ filters.
+
+ If you want to learn how to make your own application extensible
+ through plugins, we recommend that you start by reading this
+ overview, which explains how to make an application use plugins.
+ Afterward, you can read the
+ \l{plugandpaintplugins/basictools}{Basic Tools} and
+ \l{plugandpaintplugins/extrafilters}{Extra Filters}
+ overviews, which show how to implement static and dynamic
+ plugins, respectively.
+
+ Plug & Paint consists of the following classes:
+
+ \list
+ \li \c MainWindow is a QMainWindow subclass that provides the menu
+ system and that contains a \c PaintArea as the central widget.
+ \li \c PaintArea is a QWidget that allows the user to draw using a
+ brush and to insert shapes.
+ \li \c PluginDialog is a dialog that shows information about the
+ plugins detected by the application.
+ \li \c BrushInterface, \c ShapeInterface, and \c FilterInterface are
+ abstract base classes that can be implemented by plugins to
+ provide custom brushes, shapes, and image filters.
+ \endlist
+
+ \section1 The Plugin Interfaces
+
+ We will start by reviewing the interfaces defined in \c
+ interfaces.h. These interfaces are used by the Plug & Paint
+ application to access extra functionality. They are implemented
+ in the plugins.
+
+
+ \snippet tools/plugandpaint/interfaces.h 0
+
+ The \c BrushInterface class declares four pure virtual functions.
+ The first pure virtual function, \c brushes(), returns a list of
+ strings that identify the brushes provided by the plugin. By
+ returning a QStringList instead of a QString, we make it possible
+ for a single plugin to provide multiple brushes. The other
+ functions have a \c brush parameter to identify which brush
+ (among those returned by \c brushes()) is used.
+
+ \c mousePress(), \c mouseMove(), and \c mouseRelease() take a
+ QPainter and one or two \l{QPoint}s, and return a QRect
+ identifying which portion of the image was altered by the brush.
+
+ The class also has a virtual destructor. Interface classes
+ usually don't need such a destructor (because it would make
+ little sense to \c delete the object that implements the
+ interface through a pointer to the interface), but some compilers
+ emit a warning for classes that declare virtual functions but no
+ virtual destructor. We provide the destructor to keep these
+ compilers happy.
+
+ \snippet tools/plugandpaint/interfaces.h 1
+
+ The \c ShapeInterface class declares a \c shapes() function that
+ works the same as \c{BrushInterface}'s \c brushes() function, and
+ a \c generateShape() function that has a \c shape parameter.
+ Shapes are represented by a QPainterPath, a data type that can
+ represent arbitrary 2D shapes or combinations of shapes. The \c
+ parent parameter can be used by the plugin to pop up a dialog
+ asking the user to specify more information.
+
+ \snippet tools/plugandpaint/interfaces.h 2
+
+ The \c FilterInterface class declares a \c filters() function
+ that returns a list of filter names, and a \c filterImage()
+ function that applies a filter to an image.
+
+ \snippet tools/plugandpaint/interfaces.h 4
+
+ To make it possible to query at run-time whether a plugin
+ implements a given interface, we must use the \c
+ Q_DECLARE_INTERFACE() macro. The first argument is the name of
+ the interface. The second argument is a string identifying the
+ interface in a unique way. By convention, we use a "Java package
+ name" syntax to identify interfaces. If we later change the
+ interfaces, we must use a different string to identify the new
+ interface; otherwise, the application might crash. It is therefore
+ a good idea to include a version number in the string, as we did
+ above.
+
+ The \l{plugandpaintplugins/basictools}{Basic Tools} plugin
+ and the \l{plugandpaintplugins/extrafilters}{Extra Filters}
+ plugin shows how to derive from \c BrushInterface, \c
+ ShapeInterface, and \c FilterInterface.
+
+ A note on naming: It might have been tempting to give the \c
+ brushes(), \c shapes(), and \c filters() functions a more generic
+ name, such as \c keys() or \c features(). However, that would
+ have made multiple inheritance impractical. When creating
+ interfaces, we should always try to give unique names to the pure
+ virtual functions.
+
+ \section1 The MainWindow Class
+
+ The \c MainWindow class is a standard QMainWindow subclass, as
+ found in many of the other examples (e.g.,
+ \l{mainwindows/application}{Application}). Here, we'll
+ concentrate on the parts of the code that are related to plugins.
+
+ \snippet tools/plugandpaint/mainwindow.cpp 4
+
+ The \c loadPlugins() function is called from the \c MainWindow
+ constructor to detect plugins and update the \uicontrol{Brush},
+ \uicontrol{Shapes}, and \uicontrol{Filters} menus. We start by handling static
+ plugins (available through QPluginLoader::staticInstances())
+
+ To the application that uses the plugin, a Qt plugin is simply a
+ QObject. That QObject implements plugin interfaces using multiple
+ inheritance.
+
+ \snippet tools/plugandpaint/mainwindow.cpp 5
+
+ The next step is to load dynamic plugins. We initialize the \c
+ pluginsDir member variable to refer to the \c plugins
+ subdirectory of the Plug & Paint example. On Unix, this is just a
+ matter of initializing the QDir variable with
+ QApplication::applicationDirPath(), the path of the executable
+ file, and to do a \l{QDir::cd()}{cd()}. On Windows and Mac OS X,
+ this file is usually located in a subdirectory, so we need to
+ take this into account.
+
+ \snippet tools/plugandpaint/mainwindow.cpp 6
+ \snippet tools/plugandpaint/mainwindow.cpp 7
+ \snippet tools/plugandpaint/mainwindow.cpp 8
+
+ We use QDir::entryList() to get a list of all files in that
+ directory. Then we iterate over the result using \l foreach and
+ try to load the plugin using QPluginLoader.
+
+ The QObject provided by the plugin is accessible through
+ QPluginLoader::instance(). If the dynamic library isn't a Qt
+ plugin, or if it was compiled against an incompatible version of
+ the Qt library, QPluginLoader::instance() returns a null pointer.
+
+ If QPluginLoader::instance() is non-null, we add it to the menus.
+
+ \snippet tools/plugandpaint/mainwindow.cpp 9
+
+ At the end, we enable or disable the \uicontrol{Brush}, \uicontrol{Shapes},
+ and \uicontrol{Filters} menus based on whether they contain any items.
+
+ \snippet tools/plugandpaint/mainwindow.cpp 10
+
+ For each plugin (static or dynamic), we check which interfaces it
+ implements using \l qobject_cast(). First, we try to cast the
+ plugin instance to a \c BrushInterface; if it works, we call the
+ private function \c addToMenu() with the list of brushes returned
+ by \c brushes(). Then we do the same with the \c ShapeInterface
+ and the \c FilterInterface.
+
+ \snippet tools/plugandpaint/mainwindow.cpp 3
+
+ The \c aboutPlugins() slot is called on startup and can be
+ invoked at any time through the \uicontrol{About Plugins} action. It
+ pops up a \c PluginDialog, providing information about the loaded
+ plugins.
+
+ \image plugandpaint-plugindialog.png Screenshot of the Plugin dialog
+
+
+ The \c addToMenu() function is called from \c loadPlugin() to
+ create \l{QAction}s for custom brushes, shapes, or filters and
+ add them to the relevant menu. The QAction is created with the
+ plugin from which it comes from as the parent; this makes it
+ convenient to get access to the plugin later.
+
+ \snippet tools/plugandpaint/mainwindow.cpp 0
+
+ The \c changeBrush() slot is invoked when the user chooses one of
+ the brushes from the \uicontrol{Brush} menu. We start by finding out
+ which action invoked the slot using QObject::sender(). Then we
+ get the \c BrushInterface out of the plugin (which we
+ conveniently passed as the QAction's parent) and we call \c
+ PaintArea::setBrush() with the \c BrushInterface and the string
+ identifying the brush. Next time the user draws on the paint
+ area, \c PaintArea will use this brush.
+
+ \snippet tools/plugandpaint/mainwindow.cpp 1
+
+ The \c insertShape() is invoked when the use chooses one of the
+ shapes from the \uicontrol{Shapes} menu. We retrieve the QAction that
+ invoked the slot, then the \c ShapeInterface associated with that
+ QAction, and finally we call \c ShapeInterface::generateShape()
+ to obtain a QPainterPath.
+
+ \snippet tools/plugandpaint/mainwindow.cpp 2
+
+ The \c applyFilter() slot is similar: We retrieve the QAction
+ that invoked the slot, then the \c FilterInterface associated to
+ that QAction, and finally we call \c
+ FilterInterface::filterImage() to apply the filter onto the
+ current image.
+
+ \section1 The PaintArea Class
+
+ The \c PaintArea class contains some code that deals with \c
+ BrushInterface, so we'll review it briefly.
+
+ \snippet tools/plugandpaint/paintarea.cpp 0
+
+ In \c setBrush(), we simply store the \c BrushInterface and the
+ brush that are given to us by \c MainWindow.
+
+ \snippet tools/plugandpaint/paintarea.cpp 1
+
+ In the \l{QWidget::mouseMoveEvent()}{mouse move event handler},
+ we call the \c BrushInterface::mouseMove() function on the
+ current \c BrushInterface, with the current brush. The mouse
+ press and mouse release handlers are very similar.
+
+ \section1 The PluginDialog Class
+
+ The \c PluginDialog class provides information about the loaded
+ plugins to the user. Its constructor takes a path to the plugins
+ and a list of plugin file names. It calls \c findPlugins()
+ to fill the QTreeWdiget with information about the plugins:
+
+ \snippet tools/plugandpaint/plugindialog.cpp 0
+
+ The \c findPlugins() is very similar to \c
+ MainWindow::loadPlugins(). It uses QPluginLoader to access the
+ static and dynamic plugins. Its helper function \c
+ populateTreeWidget() uses \l qobject_cast() to find out which
+ interfaces are implemented by the plugins:
+
+ \snippet tools/plugandpaint/plugindialog.cpp 1
+
+ \section1 Importing Static Plugins
+
+ The \l{plugandpaintplugins/basictools}{Basic Tools} plugin
+ is built as a static plugin, to ensure that it is always
+ available to the application. This requires using the
+ Q_IMPORT_PLUGIN() macro somewhere in the application (in a \c
+ .cpp file) and specifying the plugin in the \c .pro file.
+
+ For Plug & Paint, we have chosen to put Q_IMPORT_PLUGIN() in \c
+ main.cpp:
+
+ \snippet tools/plugandpaint/main.cpp 0
+
+ The argument to Q_IMPORT_PLUGIN() is the plugin's name, as
+ specified with Q_EXPORT_PLUGIN2() in the \l{Exporting the
+ Plugin}{plugin}.
+
+ In the \c .pro file, we need to specify the static library.
+ Here's the project file for building Plug & Paint:
+
+ \snippet tools/plugandpaint/plugandpaint.pro 0
+
+ The \c LIBS line variable specifies the library \c pnp_basictools
+ located in the \c ../plugandpaintplugins/basictools directory.
+ (Although the \c LIBS syntax has a distinct Unix flavor, \c qmake
+ supports it on all platforms.)
+
+ The \c CONFIG() code at the end is necessary for this example
+ because the example is part of the Qt distribution and Qt can be
+ configured to be built simultaneously in debug and in release
+ modes. You don't need to for your own plugin applications.
+
+ This completes our review of the Plug & Paint application. At
+ this point, you might want to take a look at the
+ \l{plugandpaintplugins/basictools}{Basic Tools} example
+ plugin.
+*/
+
+/*!
+ \example tools/plugandpaintplugins/basictools
+ \title Plug & Paint Basic Tools Example
+
+ The Basic Tools example is a static plugin for the
+ \l{plugandpaint}{Plug & Paint} example. It provides a set
+ of basic brushes, shapes, and filters. Through the Basic Tools
+ example, we will review the four steps involved in writing a Qt
+ plugin:
+
+ \list 1
+ \li Declare a plugin class.
+ \li Implement the interfaces provided by the plugin.
+ \li Export the plugin using the Q_EXPORT_PLUGIN2() macro.
+ \li Build the plugin using an adequate \c .pro file.
+ \endlist
+
+ \section1 Declaration of the Plugin Class
+
+ \snippet tools/plugandpaintplugins/basictools/basictoolsplugin.h 0
+
+ We start by including \c interfaces.h, which defines the plugin
+ interfaces for the \l{plugandpaint}{Plug & Paint}
+ application. For the \c #include to work, we need to add an \c
+ INCLUDEPATH entry to the \c .pro file with the path to Qt's \c
+ examples/tools directory.
+
+ The \c BasicToolsPlugin class is a QObject subclass that
+ implements the \c BrushInterface, the \c ShapeInterface, and the
+ \c FilterInterface. This is done through multiple inheritance.
+ The \c Q_INTERFACES() macro is necessary to tell \l{moc}, Qt's
+ meta-object compiler, that the base classes are plugin
+ interfaces. Without the \c Q_INTERFACES() macro, we couldn't use
+ \l qobject_cast() in the \l{plugandpaint}{Plug & Paint}
+ application to detect interfaces.
+
+ \snippet tools/plugandpaintplugins/basictools/basictoolsplugin.h 2
+
+ In the \c public section of the class, we declare all the
+ functions from the three interfaces.
+
+ \section1 Implementation of the Brush Interface
+
+ Let's now review the implementation of the \c BasicToolsPlugin
+ member functions inherited from \c BrushInterface.
+
+ \snippet tools/plugandpaintplugins/basictools/basictoolsplugin.cpp 0
+
+ The \c brushes() function returns a list of brushes provided by
+ this plugin. We provide three brushes: \uicontrol{Pencil}, \uicontrol{Air
+ Brush}, and \uicontrol{Random Letters}.
+
+ \snippet tools/plugandpaintplugins/basictools/basictoolsplugin.cpp 1
+
+ On a mouse press event, we just call \c mouseMove() to draw the
+ spot where the event occurred.
+
+ \snippet tools/plugandpaintplugins/basictools/basictoolsplugin.cpp 2
+
+ In \c mouseMove(), we start by saving the state of the QPainter
+ and we compute a few variables that we'll need later.
+
+ \snippet tools/plugandpaintplugins/basictools/basictoolsplugin.cpp 3
+
+ Then comes the brush-dependent part of the code:
+
+ \list
+ \li If the brush is \uicontrol{Pencil}, we just call
+ QPainter::drawLine() with the current QPen.
+
+ \li If the brush is \uicontrol{Air Brush}, we start by setting the
+ painter's QBrush to Qt::Dense6Pattern to obtain a dotted
+ pattern. Then we draw a circle filled with that QBrush several
+ times, resulting in a thick line.
+
+ \li If the brush is \uicontrol{Random Letters}, we draw a random letter
+ at the new cursor position. Most of the code is for setting
+ the font to be bold and larger than the default font and for
+ computing an appropriate bounding rect.
+ \endlist
+
+ At the end, we restore the painter state to what it was upon
+ entering the function and we return the bounding rectangle.
+
+ \snippet tools/plugandpaintplugins/basictools/basictoolsplugin.cpp 4
+
+ When the user releases the mouse, we do nothing and return an
+ empty QRect.
+
+ \section1 Implementation of the Shape Interface
+
+ \snippet tools/plugandpaintplugins/basictools/basictoolsplugin.cpp 5
+
+ The plugin provides three shapes: \uicontrol{Circle}, \uicontrol{Star}, and
+ \uicontrol{Text...}. The three dots after \uicontrol{Text} are there because
+ the shape pops up a dialog asking for more information. We know
+ that the shape names will end up in a menu, so we include the
+ three dots in the shape name.
+
+ A cleaner but more complicated design would have been to
+ distinguish between the internal shape name and the name used in
+ the user interface.
+
+ \snippet tools/plugandpaintplugins/basictools/basictoolsplugin.cpp 6
+
+ The \c generateShape() creates a QPainterPath for the specified
+ shape. If the shape is \uicontrol{Text}, we pop up a QInputDialog to
+ let the user enter some text.
+
+ \section1 Implementation of the Filter Interface
+
+ \snippet tools/plugandpaintplugins/basictools/basictoolsplugin.cpp 7
+
+ The plugin provides three filters: \uicontrol{Invert Pixels}, \uicontrol{Swap
+ RGB}, and \uicontrol{Grayscale}.
+
+ \snippet tools/plugandpaintplugins/basictools/basictoolsplugin.cpp 8
+
+ The \c filterImage() function takes a filter name and a QImage as
+ parameters and returns an altered QImage. The first thing we do
+ is to convert the image to a 32-bit RGB format, to ensure that
+ the algorithms will work as expected. For example,
+ QImage::invertPixels(), which is used to implement the
+ \uicontrol{Invert Pixels} filter, gives counterintuitive results for
+ 8-bit images, because they invert the indices into the color
+ table instead of inverting the color table's entries.
+
+ \section1 Exporting the Plugin
+
+ Whereas applications have a \c main() function as their entry
+ point, plugins need to contain exactly one occurrence of the
+ Q_EXPORT_PLUGIN2() macro to specify which class provides the
+ plugin:
+
+ \snippet tools/plugandpaintplugins/basictools/basictoolsplugin.cpp 9
+
+ This line may appear in any \c .cpp file that is part of the
+ plugin's source code.
+
+ \section1 The .pro File
+
+ Here's the project file for building the Basic Tools plugin:
+
+ \snippet tools/plugandpaintplugins/basictools/basictools.pro 0
+
+ The \c .pro file differs from typical \c .pro files in many
+ respects. First, it starts with a \c TEMPLATE entry specifying \c
+ lib. (The default template is \c app.) It also adds \c plugin to
+ the \c CONFIG variable. This is necessary on some platforms to
+ avoid generating symbolic links with version numbers in the file
+ name, which is appropriate for most dynamic libraries but not for
+ plugins.
+
+ To make the plugin a static plugin, all that is required is to
+ specify \c static in addition to \c plugin. The
+ \l{plugandpaintplugins/extrafilters}{Extra Filters} plugin,
+ which is compiled as a dynamic plugin, doesn't specify \c static
+ in its \c .pro file.
+
+ The \c INCLUDEPATH variable sets the search paths for global
+ headers (i.e., header files included using \c{#include <...>}).
+ We add Qt's \c examples/tools directory (strictly speaking,
+ \c{examples/tools/plugandpaintplugins/basictools/../..}) to the
+ list, so that we can include \c <plugandpaint/interfaces.h>.
+
+ The \c TARGET variable specifies which name we want to give the
+ target library. We use \c pnp_ as the prefix to show that the
+ plugin is designed to work with Plug & Paint. On Unix, \c lib is
+ also prepended to that name. On all platforms, a
+ platform-specific suffix is appended (e.g., \c .dll on Windows,
+ \c .a on Linux).
+
+ The \c CONFIG() code at the end is necessary for this example
+ because the example is part of the Qt distribution and Qt can be
+ configured to be built simultaneously in debug and in release
+ modes. You don't need to for your own plugins.
+*/
+
+/*!
+ \example tools/plugandpaintplugins/extrafilters
+ \title Plug & Paint Extra Filters Example
+
+ The Extra Filters example is a plugin for the
+ \l{plugandpaint}{Plug & Paint} example. It provides a set
+ of filters in addition to those provided by the
+ \l{plugandpaintplugins/basictools}{Basic Tools} plugin.
+
+ Since the approach is identical to
+ \l{plugandpaintplugins/basictools}{Basic Tools}, we won't
+ review the code here. The only part of interest is the
+ \c .pro file, since Extra Filters is a dynamic plugin
+ (\l{plugandpaintplugins/basictools}{Basic Tools} is
+ linked statically into the Plug & Paint executable).
+
+ Here's the project file for building the Extra Filters plugin:
+
+ \snippet tools/plugandpaintplugins/extrafilters/extrafilters.pro 0
+
+ The \c .pro file differs from typical \c .pro files in many
+ respects. First, it starts with a \c TEMPLATE entry specifying \c
+ lib. (The default template is \c app.) It also adds \c plugin to
+ the \c CONFIG variable. This is necessary on some platforms to
+ avoid generating symbolic links with version numbers in the file
+ name, which is appropriate for most dynamic libraries but not for
+ plugins.
+
+ The \c INCLUDEPATH variable sets the search paths for global
+ headers (i.e., header files included using \c{#include <...>}).
+ We add Qt's \c examples/tools directory (strictly speaking,
+ \c{examples/tools/plugandpaintplugins/basictools/../..}) to the
+ list, so that we can include \c <plugandpaint/interfaces.h>.
+
+ The \c TARGET variable specifies which name we want to give the
+ target library. We use \c pnp_ as the prefix to show that the
+ plugin is designed to work with Plug & Paint. On Unix, \c lib is
+ also prepended to that name. On all platforms, a
+ platform-specific suffix is appended (e.g., \c .dll on Windows,
+ \c .so on Linux).
+
+ The \c DESTDIR variable specifies where we want to install the
+ plugin. We put it in Plug & Paint's \c plugins subdirectory,
+ since that's where the application looks for dynamic plugins.
+
+ The \c CONFIG() code at the end is necessary for this example
+ because the example is part of the Qt distribution and Qt can be
+ configured to be built simultaneously in debug and in release
+ modes. You don't need to for your own plugins.
+*/
diff --git a/examples/widgets/doc/src/regexp.qdoc b/examples/widgets/doc/src/regexp.qdoc
new file mode 100644
index 0000000000..a2c7b53ed2
--- /dev/null
+++ b/examples/widgets/doc/src/regexp.qdoc
@@ -0,0 +1,37 @@
+/****************************************************************************
+**
+** 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 tools/regexp
+ \title Regular Expressions Example
+
+ The Regular Expressions (RegExp) example shows how regular expressions in Qt are
+ applied to text by providing an environment in which new regular expressions can be
+ created and tested on custom text strings.
+
+ \image regexp-example.png
+*/
diff --git a/examples/widgets/doc/src/settingseditor.qdoc b/examples/widgets/doc/src/settingseditor.qdoc
new file mode 100644
index 0000000000..6d295bb928
--- /dev/null
+++ b/examples/widgets/doc/src/settingseditor.qdoc
@@ -0,0 +1,37 @@
+/****************************************************************************
+**
+** 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 tools/settingseditor
+ \title Settings Editor Example
+
+ The Settings Editor example shows how Qt's standard settings support is used in an
+ application by providing an editor that enables the user to view the settings for
+ installed applications, and modify those that can be edited.
+
+ \image settingseditor-example.png
+*/
diff --git a/examples/widgets/doc/src/styleplugin.qdoc b/examples/widgets/doc/src/styleplugin.qdoc
new file mode 100644
index 0000000000..42f35f2141
--- /dev/null
+++ b/examples/widgets/doc/src/styleplugin.qdoc
@@ -0,0 +1,137 @@
+/****************************************************************************
+**
+** 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 tools/styleplugin
+ \title Style Plugin Example
+
+ This example shows how to create a plugin that extends Qt with a new
+ GUI look and feel.
+
+ \image stylepluginexample.png
+
+ A plugin in Qt is a class stored in a shared library that can be
+ loaded by a QPluginLoader at run-time. When you create plugins in
+ Qt, they either extend a Qt application or Qt itself. Writing a
+ plugin that extends Qt itself is achieved by inheriting one of the
+ plugin \l{Plugin Classes}{base classes}, reimplementing functions
+ from that class, and adding a macro. In this example we extend Qt
+ by adding a new GUI look and feel (i.e., making a new QStyle
+ available). A high-level introduction to plugins is given in the
+ plugin \l{How to Create Qt Plugins}{overview document}.
+
+ Plugins that provide new styles inherit the QStylePlugin base
+ class. Style plugins are loaded by Qt and made available through
+ QStyleFactory; we will look at this later. We have implemented \c
+ SimpleStylePlugin, which provides \c SimpleStyle. The new style
+ contributes to widget styling by drawing button backgrounds in
+ red - not a major contribution, but it still makes a new style.
+
+ The new style is platform agnostic in the sense that it is not
+ based on any specific style implementation, but uses QProxyStyle
+ to merely tweak the looks in the current application style that
+ defaults to the native system style.
+
+ \note On some platforms, the native style will prevent the button
+ from having a red background. In this case, try to run the example
+ in another style (e.g., fusion).
+
+ We test the plugin with \c StyleWindow, in which we display a
+ QPushButton. The \c SimpleStyle and \c StyleWindow classes do not
+ contain any plugin specific functionality and their implementations
+ are trivial; we will therefore leap past them and head on to the \c
+ SimpleStylePlugin and the \c main() function. After we have looked
+ at that, we examine the plugin's profile.
+
+
+ \section1 SimpleStylePlugin Class Definition
+
+ \c SimpleStylePlugin inherits QStylePlugin and is the plugin
+ class.
+
+ \snippet tools/styleplugin/plugin/simplestyleplugin.h 0
+
+ \c keys() returns a list of style names that this plugin can
+ create, while \c create() takes such a string and returns the
+ QStyle corresponding to the key. Both functions are pure virtual
+ functions reimplemented from QStylePlugin. When an application
+ requests an instance of the \c SimpleStyle style, which this
+ plugin creates, Qt will create it with this plugin.
+
+
+ \section1 SimpleStylePlugin Class Implementation
+
+ Here is the implementation of \c keys():
+
+ \snippet tools/styleplugin/plugin/simplestyleplugin.cpp 0
+
+ Since this plugin only supports one style, we return a QStringList
+ with the class name of that style.
+
+ Here is the \c create() function:
+
+ \snippet tools/styleplugin/plugin/simplestyleplugin.cpp 1
+
+ Note that the key for style plugins are case insensitive.
+ The case sensitivity varies from plugin to plugin, so you need to
+ check this when implementing new plugins.
+
+ \section1 The \c main() function
+
+ \snippet tools/styleplugin/stylewindow/main.cpp 0
+
+ Qt loads the available style plugins when the QApplication object
+ is initialized. The QStyleFactory class knows about all styles and
+ produces them with \l{QStyleFactory::}{create()} (it is a
+ wrapper around all the style plugins).
+
+ \section1 The Simple Style Plugin Profile
+
+ The \c SimpleStylePlugin lives in its own directory and have
+ its own profile:
+
+ \snippet tools/styleplugin/plugin/plugin.pro 0
+
+ In the plugin profile we need to set the lib template as we are
+ building a shared library instead of an executable. We must also
+ set the config to plugin. We set the library to be stored in the
+ styles folder under stylewindow because this is a path in which Qt
+ will search for style plugins.
+
+ \section1 Related articles and examples
+
+ In addition to the plugin \l{How to Create Qt Plugins}{overview
+ document}, we have other examples and articles that concern
+ plugins.
+
+ In the \l{Echo Plugin Example}{echo plugin example} we show how to
+ implement plugins that extends Qt applications rather than Qt
+ itself, which is the case with the style plugin of this example.
+ The \l{Plug & Paint Example}{plug & paint} example shows how to
+ implement a static plugin as well as being a more involved example
+ on plugins that extend applications.
+*/
diff --git a/examples/widgets/doc/src/treemodelcompleter.qdoc b/examples/widgets/doc/src/treemodelcompleter.qdoc
new file mode 100644
index 0000000000..c6b7768976
--- /dev/null
+++ b/examples/widgets/doc/src/treemodelcompleter.qdoc
@@ -0,0 +1,171 @@
+/****************************************************************************
+**
+** 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 tools/treemodelcompleter
+ \title Tree Model Completer Example
+
+ The Tree Model Completer example shows how to provide completion
+ facilities for a hierarchical model, using a period as the separator
+ to access Child, GrandChild and GrandGrandChild level objects.
+
+ \image treemodelcompleter-example.png
+
+ Similar to the \l{Completer Example}, we provide QComboBox objects to
+ enable selection for completion mode and case sensitivity, as well as
+ a QCheckBox for wrap completions.
+
+ \section1 The Resource File
+
+ The contents of the TreeModelCompleter is read from \e treemodel.txt.
+ This file is embedded within the \e treemodelcompleter.qrc resource file,
+ which contains the following:
+
+ \quotefile tools/treemodelcompleter/treemodelcompleter.qrc
+
+ \section1 TreeModelCompleter Class Definition
+
+ The \c TreeModelCompleter is a subclass of QCompleter with two
+ constructors - one with \a parent as an argument and another with
+ \a parent and \a model as arguments.
+
+ \snippet tools/treemodelcompleter/treemodelcompleter.h 0
+
+ The class reimplements the protected functions
+ \l{QCompleter::splitPath()}{splitPath()} and
+ \l{QCompleter::pathFromIndex()}{pathFromIndex()} to suit a tree model.
+ For more information on customizing QCompleter to suit tree models, refer
+ to \l{QCompleter#Handling Tree Models}{Handling Tree Models}.
+
+ \c TreeModelCompleter also has a separator property which is declared
+ using the Q_PROPERTY() macro. The separator has READ and WRITE attributes
+ and the corresponding functions \c separator() and \c setSeparator(). For
+ more information on Q_PROPERTY(), refer to \l{Qt's Property System}.
+
+ \section1 TreeModelCompleter Class Implementation
+
+ The first constructor constructs a \c TreeModelCompleter object with a
+ parent while the second constructor constructs an object with a parent
+ and a QAbstractItemModel, \a model.
+
+ \snippet tools/treemodelcompleter/treemodelcompleter.cpp 0
+ \codeline
+ \snippet tools/treemodelcompleter/treemodelcompleter.cpp 1
+
+ The \c separator() function is a getter function that returns the
+ separator string.
+
+ \snippet tools/treemodelcompleter/treemodelcompleter.cpp 2
+
+ As mentioned earlier, the \c splitPath() function is reimplemented because
+ the default implementation is more suited to QDirModel or list models. In
+ order for QCompleter to split the path into a list of strings that are
+ matched at each level, we split it using QString::split() with \c sep as its
+ separator.
+
+ \snippet tools/treemodelcompleter/treemodelcompleter.cpp 3
+
+ The \c pathFromIndex() function returns data for the completionRole() for a
+ tree model. This function is reimplemented as its default implementation is
+ more suitable for list models. If there is no separator, we use
+ \l{QCompleter}'s default implementation, otherwise we use the
+ \l{QStringList::prepend()}{prepend()} function to navigate upwards and
+ accumulate the data. The function then returns a QStringList, \c dataList,
+ using a separator to join objects of different levels.
+
+ \snippet tools/treemodelcompleter/treemodelcompleter.cpp 4
+
+ \section1 MainWindow Class Definition
+
+ The \c MainWindow class is a subclass of QMainWindow and implements five
+ custom slots: \c about(), \c changeCase(), \c changeMode(),
+ \c highlight(), and \c updateContentsLabel().
+
+ \snippet tools/treemodelcompleter/mainwindow.h 0
+
+ In addition, the class has two private functions, \c createMenu() and
+ \c modelFromFile(), as well as private instances of QTreeView, QComboBox,
+ QLabel, \c TreeModelCompleter and QLineEdit.
+
+ \snippet tools/treemodelcompleter/mainwindow.h 1
+
+ \section1 MainWindow Class Implementation
+
+ The \c{MainWindow}'s constructor creates a \c MainWindow object with a
+ parent and initializes the \c completer and \c lineEdit. The
+ \c createMenu() function is invoked to set up the "File" menu and "Help"
+ menu. The \c{completer}'s model is set to the QAbstractItemModel obtained
+ from \c modelFromFile(), and the \l{QCompleter::highlighted()}
+ {highlighted()} signal is connected to \c{MainWindow}'s \c highlight()
+ slot.
+
+ \snippet tools/treemodelcompleter/mainwindow.cpp 0
+
+ The QLabel objects \c modelLabel, \c modeLabel and \c caseLabel are
+ instantiated. Also, the QComboBox objects, \c modeCombo and \c caseCombo,
+ are instantiated and populated. By default, the \c{completer}'s mode is
+ "Filtered Popup" and the case is insensitive.
+
+ \snippet tools/treemodelcompleter/mainwindow.cpp 1
+ \codeline
+ \snippet tools/treemodelcompleter/mainwindow.cpp 2
+
+ We use a QGridLayout to place all the objects in the \c MainWindow.
+
+ \snippet tools/treemodelcompleter/mainwindow.cpp 3
+
+ The \c createMenu() function sets up the QAction objects required and
+ adds them to the "File" menu and "Help" menu. The
+ \l{QAction::triggered()}{triggered()} signals from these actions are
+ connected to their respective slots.
+
+ \snippet tools/treemodelcompleter/mainwindow.cpp 4
+
+ The \c changeMode() function accepts an \a index corresponding to the
+ user's choice of completion mode and changes the \c{completer}'s mode
+ accordingly.
+
+ \snippet tools/treemodelcompleter/mainwindow.cpp 5
+
+ The \c about() function provides a brief description on the Tree Model
+ Completer example.
+
+ \snippet tools/treemodelcompleter/mainwindow.cpp 6
+
+ The \c changeCase() function alternates between \l{Qt::CaseSensitive}
+ {Case Sensitive} and \l{Qt::CaseInsensitive}{Case Insensitive} modes,
+ depending on the value of \a cs.
+
+ \snippet tools/treemodelcompleter/mainwindow.cpp 7
+
+ \section1 \c main() Function
+
+ The \c main() function instantiates \c MainWindow and invokes the
+ \l{QWidget::show()}{show()} function to display it.
+
+ \snippet tools/treemodelcompleter/main.cpp 0
+*/
diff --git a/examples/widgets/doc/src/undo.qdoc b/examples/widgets/doc/src/undo.qdoc
new file mode 100644
index 0000000000..03920e44dd
--- /dev/null
+++ b/examples/widgets/doc/src/undo.qdoc
@@ -0,0 +1,43 @@
+/****************************************************************************
+**
+** 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 tools/undo
+ \title Undo Framework
+
+ This example shows Qt's undo framework in action.
+
+ \image undodemo.png
+
+ Qt's undo framework is an implementation of the Command
+ pattern, which provides advanced undo/redo functionality.
+
+ To show the abilities of the framework, we have implemented a
+ small diagram application in which the diagram items are geometric
+ primitives. You can edit the diagram in the following ways: add,
+ move, change the color of, and delete the items.
+*/
diff --git a/examples/widgets/doc/src/undoframework.qdoc b/examples/widgets/doc/src/undoframework.qdoc
new file mode 100644
index 0000000000..849b2e6143
--- /dev/null
+++ b/examples/widgets/doc/src/undoframework.qdoc
@@ -0,0 +1,291 @@
+/****************************************************************************
+**
+** 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 tools/undoframework
+ \title Undo Framework Example
+
+ This example shows how to implement undo/redo functionality
+ with the Qt undo framework.
+
+ \image undoframeworkexample.png The Undo Diagram Example
+
+ In the Qt undo framework, all actions that the user performs are
+ implemented in classes that inherit QUndoCommand. An undo command
+ class knows how to both \l{QUndoCommand::}{redo()} - or just do
+ the first time - and \l{QUndoCommand::}{undo()} an action. For
+ each action the user performs, a command is placed on a
+ QUndoStack. Since the stack contains all commands executed
+ (stacked in chronological order) on the document, it can roll the
+ state of the document backwards and forwards by undoing and redoing
+ its commands. See the \l{Overview of Qt's Undo Framework}{overview
+ document} for a high-level introduction to the undo framework.
+
+ The undo example implements a simple diagram application. It is
+ possible to add and delete items, which are either box or
+ rectangular shaped, and move the items by dragging them with the
+ mouse. The undo stack is shown in a QUndoView, which is a list in
+ which the commands are shown as list items. Undo and redo are
+ available through the edit menu. The user can also select a command
+ from the undo view.
+
+ We use the \l{Graphics View Framework}{graphics view
+ framework} to implement the diagram. We only treat the related
+ code briefly as the framework has examples of its own (e.g., the
+ \l{Diagram Scene Example}).
+
+ The example consists of the following classes:
+
+ \list
+ \li \c MainWindow is the main window and arranges the
+ example's widgets. It creates the commands based
+ on user input and keeps them on the command stack.
+ \li \c AddCommand adds an item to the scene.
+ \li \c DeleteCommand deletes an item from the scene.
+ \li \c MoveCommand when an item is moved the MoveCommand keeps record
+ of the start and stop positions of the move, and it
+ moves the item according to these when \c redo() and \c undo()
+ is called.
+ \li \c DiagramScene inherits QGraphicsScene and
+ emits signals for the \c MoveComands when an item is moved.
+ \li \c DiagramItem inherits QGraphicsPolygonItem and represents
+ an item in the diagram.
+ \endlist
+
+ \section1 MainWindow Class Definition
+
+ \snippet tools/undoframework/mainwindow.h 0
+
+ The \c MainWindow class maintains the undo stack, i.e., it creates
+ \l{QUndoCommand}s and pushes and pops them from the stack when it
+ receives the \c triggered() signal from \c undoAction and \c
+ redoAction.
+
+ \section1 MainWindow Class Implementation
+
+ We will start with a look at the constructor:
+
+ \snippet tools/undoframework/mainwindow.cpp 0
+
+ In the constructor, we set up the DiagramScene and QGraphicsView.
+
+ Here is the \c createUndoView() function:
+
+ \snippet tools/undoframework/mainwindow.cpp 1
+
+ The QUndoView is a widget that display the text, which is set with
+ the \l{QUndoCommand::}{setText()} function, for each QUndoCommand
+ in the undo stack in a list.
+
+ Here is the \c createActions() function:
+
+ \snippet tools/undoframework/mainwindow.cpp 2
+ \codeline
+ \snippet tools/undoframework/mainwindow.cpp 3
+ \dots
+ \snippet tools/undoframework/mainwindow.cpp 5
+
+ The \c createActions() function sets up all the examples actions
+ in the manner shown above. The
+ \l{QUndoStack::}{createUndoAction()} and
+ \l{QUndoStack::}{createRedoAction()} helps us crate actions that
+ are disabled and enabled based on the state of the stack. Also,
+ the text of the action will be updated automatically based on the
+ \l{QUndoCommand::}{text()} of the undo commands. For the other
+ actions we have implemented slots in the \c MainWindow class.
+
+ Here is the \c createMenus() function:
+
+ \snippet tools/undoframework/mainwindow.cpp 6
+
+ \dots
+ \snippet tools/undoframework/mainwindow.cpp 7
+ \dots
+ \snippet tools/undoframework/mainwindow.cpp 8
+
+ We have to use the QMenu \c aboutToShow() and \c aboutToHide()
+ signals since we only want \c deleteAction to be enabled when we
+ have selected an item.
+
+ Here is the \c itemMoved() slot:
+
+ \snippet tools/undoframework/mainwindow.cpp 9
+
+ We simply push a MoveCommand on the stack, which calls \c redo()
+ on it.
+
+ Here is the \c deleteItem() slot:
+
+ \snippet tools/undoframework/mainwindow.cpp 10
+
+ An item must be selected to be deleted. We need to check if it is
+ selected as the \c deleteAction may be enabled even if an item is
+ not selected. This can happen as we do not catch a signal or event
+ when an item is selected.
+
+ Here is the \c itemMenuAboutToShow() and itemMenuAboutToHide() slots:
+
+ \snippet tools/undoframework/mainwindow.cpp 11
+ \codeline
+ \snippet tools/undoframework/mainwindow.cpp 12
+
+ We implement \c itemMenuAboutToShow() and \c itemMenuAboutToHide()
+ to get a dynamic item menu. These slots are connected to the
+ \l{QMenu::}{aboutToShow()} and \l{QMenu::}{aboutToHide()} signals.
+ We need this to disable or enable the \c deleteAction.
+
+ Here is the \c addBox() slot:
+
+ \snippet tools/undoframework/mainwindow.cpp 13
+
+ The \c addBox() function creates an AddCommand and pushes it on
+ the undo stack.
+
+ Here is the \c addTriangle() sot:
+
+ \snippet tools/undoframework/mainwindow.cpp 14
+
+ The \c addTriangle() function creates an AddCommand and pushes it
+ on the undo stack.
+
+ Here is the implementation of \c about():
+
+ \snippet tools/undoframework/mainwindow.cpp 15
+
+ The about slot is triggered by the \c aboutAction and displays an
+ about box for the example.
+
+ \section1 AddCommand Class Definition
+
+ \snippet tools/undoframework/commands.h 2
+
+ The \c AddCommand class adds DiagramItem graphics items to the
+ DiagramScene.
+
+ \section1 AddCommand Class Implementation
+
+ We start with the constructor:
+
+ \snippet tools/undoframework/commands.cpp 7
+
+ We first create the DiagramItem to add to the DiagramScene. The
+ \l{QUndoCommand::}{setText()} function let us set a QString that
+ describes the command. We use this to get custom messages in the
+ QUndoView and in the menu of the main window.
+
+ \snippet tools/undoframework/commands.cpp 8
+
+ \c undo() removes the item from the scene.
+
+ \snippet tools/undoframework/commands.cpp 9
+
+ We set the position of the item as we do not do this in the
+ constructor.
+
+ \section1 DeleteCommand Class Definition
+
+ \snippet tools/undoframework/commands.h 1
+
+ The DeleteCommand class implements the functionality to remove an
+ item from the scene.
+
+ \section1 DeleteCommand Class Implementation
+
+ \snippet tools/undoframework/commands.cpp 4
+
+ We know that there must be one selected item as it is not possible
+ to create a DeleteCommand unless the item to be deleted is
+ selected and that only one item can be selected at any time.
+ The item must be unselected if it is inserted back into the
+ scene.
+
+ \snippet tools/undoframework/commands.cpp 5
+
+ The item is simply reinserted into the scene.
+
+ \snippet tools/undoframework/commands.cpp 6
+
+ The item is removed from the scene.
+
+ \section1 MoveCommand Class Definition
+
+ \snippet tools/undoframework/commands.h 0
+
+ The \l{QUndoCommand::}{mergeWith()} is reimplemented to make
+ consecutive moves of an item one MoveCommand, i.e, the item will
+ be moved back to the start position of the first move.
+
+ \section1 MoveCommand Class Implementation
+
+
+ The constructor of MoveCommand looks like this:
+
+ \snippet tools/undoframework/commands.cpp 0
+
+ We save both the old and new positions for undo and redo
+ respectively.
+
+ \snippet tools/undoframework/commands.cpp 2
+
+ We simply set the items old position and update the scene.
+
+ \snippet tools/undoframework/commands.cpp 3
+
+ We set the item to its new position.
+
+ \snippet tools/undoframework/commands.cpp 1
+
+ Whenever a MoveCommand is created, this function is called to
+ check if it should be merged with the previous command. It is the
+ previous command object that is kept on the stack. The function
+ returns true if the command is merged; otherwise false.
+
+ We first check whether it is the same item that has been moved
+ twice, in which case we merge the commands. We update the position
+ of the item so that it will take the last position in the move
+ sequence when undone.
+
+ \section1 DiagramScene Class Definition
+
+ \snippet tools/undoframework/diagramscene.h 0
+
+ The DiagramScene implements the functionality to move a
+ DiagramItem with the mouse. It emits a signal when a move is
+ completed. This is caught by the \c MainWindow, which makes
+ MoveCommands. We do not examine the implementation of DiagramScene
+ as it only deals with graphics framework issues.
+
+ \section1 The \c main() Function
+
+ The \c main() function of the program looks like this:
+
+ \snippet tools/undoframework/main.cpp 0
+
+ We draw a grid in the background of the DiagramScene, so we use a
+ resource file. The rest of the function creates the \c MainWindow and
+ shows it as a top level window.
+*/