In-App purchasing demo

 /****************************************************************************
 **
 ** Copyright (C) 2021 The Qt Company Ltd.
 ** Contact: https://www.qt.io/licensing/
 **
 ** This file is part of the examples 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."
 **
 ** $QT_END_LICENSE$
 **
 ****************************************************************************/

 #ifndef IOSINAPPPURCHASEBACKEND_H
 #define IOSINAPPPURCHASEBACKEND_H

 #include "../inapp/inapppurchasebackend.h"
 #include "../inapp/inappproduct.h"
 #include "../inapp/inapptransaction.h"

 #include <QtCore/QHash>

 Q_FORWARD_DECLARE_OBJC_CLASS(QT_MANGLE_NAMESPACE(InAppPurchaseManager));

 class IosInAppPurchaseProduct;
 class IosInAppPurchaseTransaction;

 class IosInAppPurchaseBackend : public InAppPurchaseBackend
 {
     Q_OBJECT
 public:
     IosInAppPurchaseBackend(QObject *parent = 0);
     ~IosInAppPurchaseBackend();

     void initialize();
     bool isReady() const;
     void queryProduct(InAppProduct::ProductType productType, const QString &identifier);
     void restorePurchases();
     void setPlatformProperty(const QString &propertyName, const QString &value);

     //Called by InAppPurchaseManager
     Q_INVOKABLE void registerProduct(IosInAppPurchaseProduct *product);
     Q_INVOKABLE void registerQueryFailure(const QString &productId);
     Q_INVOKABLE void registerTransaction(IosInAppPurchaseTransaction *transaction);
     InAppProduct::ProductType productTypeForProductId(const QString &productId);
     IosInAppPurchaseProduct *registeredProductForProductId(const QString &productId);

 private:
     QT_MANGLE_NAMESPACE(InAppPurchaseManager) *m_iapManager;
     QHash<QString, InAppProduct::ProductType> m_productTypeForPendingId;
     QHash<QString, IosInAppPurchaseProduct*> m_registeredProductForId;

 private slots:
     void setParentToBackend(QObject *object);
 };


 #endif // IOSINAPPPURCHASEBACKEND_H