/**************************************************************************** ** ** Copyright (C) 2020 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the documentation of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:BSD$ ** 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. ** ** BSD License Usage ** Alternatively, you may use this file under the terms of the BSD license ** as follows: ** ** "Redistribution and use in source and binary forms, with or without ** modification, are permitted provided that the following conditions are ** met: ** * Redistributions of source code must retain the above copyright ** notice, this list of conditions and the following disclaimer. ** * Redistributions in binary form must reproduce the above copyright ** notice, this list of conditions and the following disclaimer in ** the documentation and/or other materials provided with the ** distribution. ** * Neither the name of The Qt Company Ltd nor the names of its ** contributors may be used to endorse or promote products derived ** from this software without specific prior written permission. ** ** ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." ** ** $QT_END_LICENSE$ ** ****************************************************************************/ #include #include //! [0] class MyClass : public QObject { Q_OBJECT Q_PROPERTY(int x READ x WRITE setX NOTIFY xChanged BINDABLE bindableX) public: int x() const { return xProp; } void setX(int x) { xProp = x; } QBindable bindableX() { return QBindable(&xProp); } signals: void xChanged(); private: // Declare the instance of the bindable property data. Q_OBJECT_BINDABLE_PROPERTY(MyClass, int, xProp, &MyClass::xChanged) }; //! [0] //! [1] class MyClass : public QObject { Q_OBJECT Q_PROPERTY(int x READ x WRITE setX NOTIFY xChanged BINDABLE bindableX) public: int x() const { return xProp; } void setX(int x) { xProp = x; } QBindable bindableX() { return QBindable(&xProp); } signals: void xChanged(); private: // Declare the instance of int bindable property data and // initialize it with the value 5. // This is similar to declaring // int xProp = 5; // without using the new QObjectBindableProperty class. Q_OBJECT_BINDABLE_PROPERTY_WITH_ARGS(MyClass, int, xProp, 5, &MyClass::xChanged) }; //! [1] //! [2] class CustomType { public: CustomType(int val, int otherVal) : value(val), anotherValue(otherVal) { } private: int value = 0; int anotherValue = 0; }; // later when using CustomType as a property Q_OBJECT_BINDABLE_PROPERTY_WITH_ARGS(MyClass, CustomType xProp, CustomType(5, 10), &MyClass::xChanged) //! [2] void usage_QBindable() { //! [3] MyClass *myObject; QBindable bindableX = myObject->bindableX(); qDebug() << bindableX.hasBinding(); // prints false QProperty y {42}; bindableX.setBinding([&](){ return 2*y.value(); }); qDebug() << bindableX.hasBinding() << myObject->x(); // prints true 84 //! [3] }