| /**************************************************************************** |
| ** |
| ** Copyright (C) 2016 The Qt Company Ltd. |
| ** Contact: https://www.qt.io/licensing/ |
| ** |
| ** This file is part of the documentation of the Qt Toolkit. |
| ** |
| ** $QT_BEGIN_LICENSE:BSD$ |
| ** 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 |
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| ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
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| ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." |
| ** |
| ** $QT_END_LICENSE$ |
| ** |
| ****************************************************************************/ |
| |
| //! [0] |
| struct MyStruct |
| { |
| int i; |
| ... |
| }; |
| |
| Q_DECLARE_METATYPE(MyStruct) |
| //! [0] |
| |
| |
| //! [1] |
| namespace MyNamespace |
| { |
| ... |
| } |
| |
| Q_DECLARE_METATYPE(MyNamespace::MyStruct) |
| //! [1] |
| |
| |
| //! [2] |
| MyStruct s; |
| QVariant var; |
| var.setValue(s); // copy s into the variant |
| |
| ... |
| |
| // retrieve the value |
| MyStruct s2 = var.value<MyStruct>(); |
| //! [2] |
| |
| |
| //! [3] |
| int id = QMetaType::type("MyClass"); |
| if (id != QMetaType::UnknownType) { |
| void *myClassPtr = QMetaType::create(id); |
| ... |
| QMetaType::destroy(id, myClassPtr); |
| myClassPtr = 0; |
| } |
| //! [3] |
| |
| |
| //! [4] |
| qRegisterMetaType<MyClass>("MyClass"); |
| //! [4] |
| |
| |
| //! [5] |
| qRegisterMetaTypeStreamOperators<MyClass>("MyClass"); |
| //! [5] |
| |
| |
| //! [6] |
| QDataStream &operator<<(QDataStream &out, const MyClass &myObj); |
| QDataStream &operator>>(QDataStream &in, MyClass &myObj); |
| //! [6] |
| |
| |
| //! [7] |
| int id = qRegisterMetaType<MyStruct>(); |
| //! [7] |
| |
| |
| //! [8] |
| int id = qMetaTypeId<QString>(); // id is now QMetaType::QString |
| id = qMetaTypeId<MyStruct>(); // compile error if MyStruct not declared |
| //! [8] |
| |
| //! [9] |
| typedef QString CustomString; |
| qRegisterMetaType<CustomString>("CustomString"); |
| //! [9] |
| |
| //! [10] |
| |
| #include <deque> |
| |
| Q_DECLARE_SEQUENTIAL_CONTAINER_METATYPE(std::deque) |
| |
| void someFunc() |
| { |
| std::deque<QFile*> container; |
| QVariant var = QVariant::fromValue(container); |
| // ... |
| } |
| |
| //! [10] |
| |
| //! [11] |
| |
| #include <unordered_list> |
| |
| Q_DECLARE_ASSOCIATIVE_CONTAINER_METATYPE(std::unordered_map) |
| |
| void someFunc() |
| { |
| std::unordered_map<int, bool> container; |
| QVariant var = QVariant::fromValue(container); |
| // ... |
| } |
| |
| //! [11] |
| |
| //! [12] |
| QPointer<QFile> fp(new QFile); |
| QVariant var = QVariant::fromValue(fp); |
| // ... |
| if (var.canConvert<QObject*>()) { |
| QObject *sp = var.value<QObject*>(); |
| qDebug() << sp->metaObject()->className(); // Prints 'QFile'. |
| } |
| //! [12] |
| |
| //! [13] |
| |
| #include <memory> |
| |
| Q_DECLARE_SMART_POINTER_METATYPE(std::shared_ptr) |
| |
| void someFunc() |
| { |
| auto smart_ptr = std::make_shared<QFile>(); |
| QVariant var = QVariant::fromValue(smart_ptr); |
| // ... |
| if (var.canConvert<QObject*>()) { |
| QObject *sp = var.value<QObject*>(); |
| qDebug() << sp->metaObject()->className(); // Prints 'QFile'. |
| } |
| } |
| |
| //! [13] |