In-App purchasing demo

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 #ifndef INAPPPRODUCTQMLTYPE_H
 #define INAPPPRODUCTQMLTYPE_H

 #include <QtQml/qqmlparserstatus.h>
 #include <QObject>
 #include <QtQml/qqml.h>

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

 class InAppTransaction;
 class InAppStoreQmlType;
 class InAppProductQmlType : public QObject, public QQmlParserStatus
 {
     Q_OBJECT
     Q_INTERFACES(QQmlParserStatus)
     Q_PROPERTY(QString identifier READ identifier WRITE setIdentifier NOTIFY identifierChanged)
     Q_PROPERTY(ProductType type READ type WRITE setType NOTIFY typeChanged)
     Q_PROPERTY(QString price READ price NOTIFY priceChanged)
     Q_PROPERTY(QString title READ title NOTIFY titleChanged)
     Q_PROPERTY(QString description READ description NOTIFY descriptionChanged)
     Q_PROPERTY(Status status READ status NOTIFY statusChanged)
     Q_PROPERTY(InAppStoreQmlType *store READ store WRITE setStore NOTIFY storeChanged)
     QML_NAMED_ELEMENT(Product)

 public:
     enum Status {
         Uninitialized,
         PendingRegistration,
         Registered,
         Unknown
     };
     Q_ENUM(Status);

     // Must match InAppProduct::ProductType
     enum ProductType {
         Consumable,
         Unlockable
     };
     Q_ENUM(ProductType);

     explicit InAppProductQmlType(QObject *parent = 0);

     Q_INVOKABLE void purchase();
     Q_INVOKABLE void resetStatus();

     void setIdentifier(const QString &identifier);
     QString identifier() const;

     Status status() const;
     QString price() const;
     QString title() const;
     QString description() const;

     void setStore(InAppStoreQmlType *store);
     InAppStoreQmlType *store() const;

     void setType(ProductType type);
     ProductType type() const;

 Q_SIGNALS:
     void purchaseSucceeded(InAppTransaction *transaction);
     void purchaseFailed(InAppTransaction *transaction);
     void purchaseRestored(InAppTransaction *transaction);
     void identifierChanged();
     void statusChanged();
     void priceChanged();
     void titleChanged();
     void descriptionChanged();
     void storeChanged();
     void typeChanged();

 protected:
     void componentComplete();
     void classBegin() {}

 private Q_SLOTS:
     void handleTransaction(InAppTransaction *transaction);
     void handleProductRegistered(InAppProduct *product);
     void handleProductUnknown(InAppProduct::ProductType, const QString &identifier);

 private:
     void setProduct(InAppProduct *product);
     void updateProduct();

     QString m_identifier;
     Status m_status;
     InAppProductQmlType::ProductType m_type;
     bool m_componentComplete;

     InAppStoreQmlType *m_store;
     InAppProduct *m_product;
 };

 #endif // INAPPPRODUCTQMLTYPE_H