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/****************************************************************************
**
** Copyright (C) 2018 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the Qt Creator documentation.
**
** 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.
**
****************************************************************************/
/*!
\previouspage quick-property-bindings.html
\page quick-connections-backend.html
\nextpage quick-states.html
\title Managing C++ Backend Objects
Many applications provide QObject objects implemented in C++ that work as a
bridge between QML and C++. Such objects are typically registered with
\c qmlRegisterType or \c qmlRegisterSingletonType and then used by QML to
communicate with the C++ backend. Another example of such objects are the
state machines created by the \l {Using the Qt SCXML Compiler (qscxmlc)}
{Qt SCXML Compiler}.
Backend objects in a QML file are accessible if the QML file contains the
required imports. In addition, for a non-singleton QObject, a dynamic
property that contains the QObject must be specified.
A \e local QObject is instantiated in the current \e .qml file, as follows:
\badcode
property MyType myType: MyType {}.
\endcode
Otherwise the property is just defined, as follows:
\badcode
property MyType myType
\endcode
To manage backend objects:
\list 1
\li In the \uicontrol {Connections} view, select the
\uicontrol Backends tab to view accessible backend objects.
\image qmldesigner-backends.png
\li Select the \inlineimage plus.png
(\uicontrol Add) button to add a backend object in the
\uicontrol {Add New C++ Backend} dialog.
\li In the \uicontrol Type field, select the type of the backend QObject
to add.
\li Select the \uicontrol {Define object locally} check box if the
QObject is not registered as a singleton.
\li Select \uicontrol OK to add the required import and to create the
property for a non-singleton object.
\endlist
*/
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