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diff --git a/doc/src/examples/customtypesending.qdoc b/doc/src/examples/customtypesending.qdoc deleted file mode 100644 index 9fd64b42fd..0000000000 --- a/doc/src/examples/customtypesending.qdoc +++ /dev/null @@ -1,121 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2016 The Qt Company Ltd. -** Contact: https://www.qt.io/licensing/ -** -** 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 The Qt Company. For licensing terms -** and conditions see https://www.qt.io/terms-conditions. For further -** information use the contact form at https://www.qt.io/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: https://www.gnu.org/licenses/fdl-1.3.html. -** $QT_END_LICENSE$ -** -****************************************************************************/ - -/*! - \example tools/customtypesending - \title Custom Type Sending Example - - The Custom Type Sending example shows how to use a custom type with signals - and slots. - - \image customtypesending-example.png - - \section1 Overview - - In the \l{Custom Type Example}, we showed how to integrate custom types - with the meta-object system, enabling them to be stored in QVariant - objects, written out in debugging information and used in signal-slot - communication. - - In this example, we demonstrate that the preparations made to the - \c Message class and its declaration with Q_DECLARE_METATYPE() enable it - to be used with direct signal-slot connections. We do this by creating - a \c Window class containing signals and slots whose signatures include - \c Message arguments. - - \section1 The Window and Message Class Definitions - - We define a simple \c Window class with a signal and public slot that - allow a \c Message object to be sent via a signal-slot connection: - - \snippet examples/tools/customtypesending/window.h Window class definition - - The window will contain a text editor to show the contents of a message - and a push button that the user can click to send a message. To facilitate - this, we also define the \c sendMessage() slot. We also keep a \c Message - instance in the \c thisMessage private variable which holds the actual - message to be sent. - - The \c Message class is defined in the following way: - - \snippet examples/tools/customtypesending/message.h custom type definition - - The type is declared to the meta-type system with the Q_DECLARE_METATYPE() - macro: - - \snippet examples/tools/customtypesending/message.h custom type meta-type declaration - - This will make the type available for use in direct signal-slot connections. - - \section1 The Window Class Implementation - - The \c Window constructor sets up a user interface containing a text - editor and a push button. - - \snippet examples/tools/customtypesending/window.cpp Window constructor - - The button's \l{QPushButton::}{clicked()} signal is connected to the - window's \c{sendMessage()} slot, which emits the \c{messageSent(Message)} - signal with the \c Message held by the \c thisMessage variable: - - \snippet examples/tools/customtypesending/window.cpp sending a message - - We implement a slot to allow the message to be received, and this also - lets us set the message in the window programatically: - - \snippet examples/tools/customtypesending/window.cpp receiving a message - - In this function, we simply assign the new message to \c thisMessage - and update the text in the editor. - - \section1 Making the Connection - - In the example's \c{main()} function, we perform the connection between - two instances of the \c Window class: - - \snippet examples/tools/customtypesending/main.cpp main function - - We set the message for the first window and connect the - \c{messageSent(Message)} signal from each window to the other's - \c{setMessage(Message)} slot. Since the signals and slots mechanism is only - concerned with the type, we can simplify the signatures of both the - signal and slot when we make the connection. - - When the user clicks on the \uicontrol{Send message} button in either window, - the message shown will be emitted in a signal that the other window will - receive and display. - - \section1 Further Reading - - Although the custom \c Message type can be used with direct signals and - slots, an additional registration step needs to be performed if you want - to use it with queued signal-slot connections. See the - \l{Queued Custom Type Example} for details. - - More information on using custom types with Qt can be found in the - \l{Creating Custom Qt Types} document. -*/ |