In-App purchasing demo

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 #ifndef INAPPTRANSACTION_H
 #define INAPPTRANSACTION_H

 #include <QtCore/qobject.h>
 #include <QtCore/qsharedpointer.h>
 #include <QDateTime>
 #include <QtQml/qqml.h>

 #include "inappproduct.h"

 class InAppProduct;
 class InAppTransactionPrivate;
 class InAppTransaction: public QObject
 {
     Q_OBJECT
     Q_PROPERTY(TransactionStatus status READ status CONSTANT)
     Q_PROPERTY(InAppProduct* product READ product CONSTANT)
     Q_PROPERTY(QString orderId READ orderId CONSTANT)
     Q_PROPERTY(FailureReason failureReason READ failureReason CONSTANT)
     Q_PROPERTY(QString errorString READ errorString CONSTANT)
     Q_PROPERTY(QDateTime timestamp READ timestamp CONSTANT)
     QML_NAMED_ELEMENT(Transaction)
     QML_UNAVAILABLE

 public:
     enum TransactionStatus {
         Unknown,
         PurchaseApproved,
         PurchaseFailed,
         PurchaseRestored
     };
     Q_ENUM(TransactionStatus);

     enum FailureReason {
         NoFailure,
         CanceledByUser,
         ErrorOccurred
     };
     Q_ENUM(FailureReason);

     ~InAppTransaction();

     InAppProduct *product() const;

     virtual QString orderId() const;
     virtual FailureReason failureReason() const;
     virtual QString errorString() const;
     virtual QDateTime timestamp() const;

     Q_INVOKABLE virtual void finalize() = 0;
     Q_INVOKABLE virtual QString platformProperty(const QString &propertyName) const;

     TransactionStatus status() const;

 protected:
     explicit InAppTransaction(TransactionStatus status,
                                InAppProduct *product,
                                QObject *parent = nullptr);

 private:
     Q_DISABLE_COPY(InAppTransaction)
     QSharedPointer<InAppTransactionPrivate> d;
 };

 #endif // INAPPTRANSACTION_H