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diff --git a/doc/src/examples/customtype.qdoc b/doc/src/examples/customtype.qdoc deleted file mode 100644 index b2f86d6890..0000000000 --- a/doc/src/examples/customtype.qdoc +++ /dev/null @@ -1,143 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies). -** Contact: http://www.qt-project.org/ -** -** This file is part of the documentation of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:FDL$ -** GNU Free Documentation License -** 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. -** -** Other Usage -** Alternatively, this file may be used in accordance with the terms -** and conditions contained in a signed written agreement between you -** and Nokia. -** -** -** -** -** -** $QT_END_LICENSE$ -** -****************************************************************************/ - -/*! - \example tools/customtype - \title Custom Type Example - - The Custom Type example shows how to integrate a custom type into Qt's - meta-object system. - - Contents: - - \tableofcontents - - \section1 Overview - - Qt provides a range of standard value types that are used to provide - rich and meaningful APIs. These types are integrated with the meta-object - system, enabling them to be stored in QVariant objects, written out in - debugging information and sent between components in signal-slot - communication. - - Custom types can also be integrated with the meta-object system as long as - they are written to conform to some simple guidelines. In this example, we - introduce a simple \c Message class, we describe how we make it work with - QVariant, and we show how it can be extended to generate a printable - representation of itself for use in debugging output. - - \section1 The Message Class Definition - - The \c Message class is a simple value class that contains two pieces - of information (a QString and a QStringList), each of which can be read - using trivial getter functions: - - \snippet examples/tools/customtype/message.h custom type definition - - The default constructor, copy constructor and destructor are - all required, and must be public, if the type is to be integrated into the - meta-object system. Other than this, we are free to implement whatever we - need to make the type do what we want, so we also include a constructor - that lets us set the type's data members. - - To enable the type to be used with QVariant, we declare it using the - Q_DECLARE_METATYPE() macro: - - \snippet examples/tools/customtype/message.h custom type meta-type declaration - - We do not need to write any additional code to accompany this macro. - - To allow us to see a readable description of each \c Message object when it - is sent to the debug output stream, we define a streaming operator: - - \snippet examples/tools/customtype/message.h custom type streaming operator - - This facility is useful if you need to insert tracing statements in your - code for debugging purposes. - - \section1 The Message Class Implementation - - The implementation of the default constructor, copy constructor and destructor - are straightforward for the \c Message class: - - \snippet examples/tools/customtype/message.cpp Message class implementation - - The streaming operator is implemented in the following way: - - \snippet examples/tools/customtype/message.cpp custom type streaming operator - - Here, we want to represent each value depending on how many lines are stored - in the message body. We stream text to the QDebug object passed to the - operator and return the QDebug object obtained from its maybeSpace() member - function; this is described in more detail in the - \l{Creating Custom Qt Types#Making the Type Printable}{Creating Custom Qt Types} - document. - - We include the code for the getter functions for completeness: - - \snippet examples/tools/customtype/message.cpp getter functions - - With the type fully defined, implemented, and integrated with the - meta-object system, we can now use it. - - \section1 Using the Message - - In the example's \c{main()} function, we show how a \c Message object can - be printed to the console by sending it to the debug stream: - - \snippet examples/tools/customtype/main.cpp printing a custom type - - You can use the type with QVariant in exactly the same way as you would - use standard Qt value types. Here's how to store a value using the - QVariant::setValue() function: - - \snippet examples/tools/customtype/main.cpp storing a custom value - - Alternatively, the QVariant::fromValue() and qVariantSetValue() functions - can be used if you are using a compiler without support for member template - functions. - - The value can be retrieved using the QVariant::value() member template - function: - - \snippet examples/tools/customtype/main.cpp retrieving a custom value - - Alternatively, the qVariantValue() template function can be used if - you are using a compiler without support for member template functions. - - \section1 Further Reading - - The custom \c Message type can also be used with direct signal-slot - connections; see the \l{Custom Type Sending Example} for a demonstration - of this. - To register a custom type for use with queued signals and slots, such as - those used in cross-thread communication, see the - \l{Queued Custom Type Example}. - - More information on using custom types with Qt can be found in the - \l{Creating Custom Qt Types} document. -*/ |