qbindingstorage.h

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#ifndef QBINDINGSTORAGE_H
#define QBINDINGSTORAGE_H
 
#include <QtCore/qglobal.h>
#include <QtCore/qnamespace.h>
 
QT_BEGIN_NAMESPACE
 
template <typename Class, typename T, auto Offset, auto Setter, auto Signal, auto Getter>
class QObjectCompatProperty;
struct QPropertyDelayedNotifications;
class QUntypedPropertyData;
 
namespace QtPrivate {
 
class QPropertyBindingData;
struct BindingEvaluationState;
struct CompatPropertySafePoint;
}
 
struct QBindingStatus
{
    QtPrivate::BindingEvaluationState *currentlyEvaluatingBinding = nullptr;
    QtPrivate::CompatPropertySafePoint *currentCompatProperty = nullptr;
    Qt::HANDLE threadId = nullptr;
    QPropertyDelayedNotifications *groupUpdateData = nullptr;
};
 
 
struct QBindingStorageData;
class Q_CORE_EXPORT QBindingStorage
{
    mutable QBindingStorageData *d = nullptr;
    QBindingStatus *bindingStatus = nullptr;
 
    template<typename Class, typename T, auto Offset, auto Setter, auto Signal, auto Getter>
    friend class QObjectCompatProperty;
    friend class QObjectPrivate;
    friend class QtPrivate::QPropertyBindingData;
public:
    QBindingStorage();
    ~QBindingStorage();
 
    bool isEmpty() { return !d; }
 
    void registerDependency(const QUntypedPropertyData *data) const
    {
        if (!bindingStatus->currentlyEvaluatingBinding)
            return;
        registerDependency_helper(data);
    }
    QtPrivate::QPropertyBindingData *bindingData(const QUntypedPropertyData *data) const
    {
        if (!d)
            return nullptr;
        return bindingData_helper(data);
    }
 
#if QT_CORE_REMOVED_SINCE(6, 2)
    void maybeUpdateBindingAndRegister(const QUntypedPropertyData *data) const { registerDependency(data); }
#endif
 
    QtPrivate::QPropertyBindingData *bindingData(QUntypedPropertyData *data, bool create)
    {
        if (!d && !create)
            return nullptr;
        return bindingData_helper(data, create);
    }
private:
    void clear();
    void registerDependency_helper(const QUntypedPropertyData *data) const;
#if QT_CORE_REMOVED_SINCE(6, 2)
    // ### Unused, but keep for BC
    void maybeUpdateBindingAndRegister_helper(const QUntypedPropertyData *data) const;
#endif
    QtPrivate::QPropertyBindingData *bindingData_helper(const QUntypedPropertyData *data) const;
    QtPrivate::QPropertyBindingData *bindingData_helper(QUntypedPropertyData *data, bool create);
};
 
QT_END_NAMESPACE
 
#endif // QBINDINGSTORAGE_H