source: trunk/src/declarative/qml/qdeclarativebinding_p.h

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#ifndef QDECLARATIVEBINDING_P_H
#define QDECLARATIVEBINDING_P_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//

#include "qdeclarative.h"
#include "qdeclarativepropertyvaluesource.h"
#include "qdeclarativeexpression.h"
#include "qdeclarativeproperty.h"
#include "private/qdeclarativeproperty_p.h"

#include <QtCore/QObject>
#include <QtCore/QMetaProperty>

QT_BEGIN_NAMESPACE

class Q_DECLARATIVE_PRIVATE_EXPORT QDeclarativeAbstractBinding
{
public:
    typedef QWeakPointer<QDeclarativeAbstractBinding> Pointer;

    QDeclarativeAbstractBinding();

    virtual void destroy();

    virtual QString expression() const;

    enum Type { PropertyBinding, ValueTypeProxy };
    virtual Type bindingType() const { return PropertyBinding; }

    QObject *object() const;
    int propertyIndex() const;

    void setEnabled(bool e) { setEnabled(e, QDeclarativePropertyPrivate::DontRemoveBinding); }
    virtual void setEnabled(bool, QDeclarativePropertyPrivate::WriteFlags) = 0;

    void update() { update(QDeclarativePropertyPrivate::DontRemoveBinding); }
    virtual void update(QDeclarativePropertyPrivate::WriteFlags) = 0;

    void addToObject(QObject *, int);
    void removeFromObject();

    static Pointer getPointer(QDeclarativeAbstractBinding *p) { return p ? p->weakPointer() : Pointer(); }

protected:
    virtual ~QDeclarativeAbstractBinding();
    void clear();

private:
    Pointer weakPointer();

    friend class QDeclarativeData;
    friend class QDeclarativeComponentPrivate;
    friend class QDeclarativeValueTypeProxyBinding;
    friend class QDeclarativePropertyPrivate;
    friend class QDeclarativeVME;
    friend class QtSharedPointer::ExternalRefCount<QDeclarativeAbstractBinding>;

    QObject *m_object;
    int m_propertyIndex;
    QDeclarativeAbstractBinding **m_mePtr;
    QDeclarativeAbstractBinding **m_prevBinding;
    QDeclarativeAbstractBinding  *m_nextBinding;
    QSharedPointer<QDeclarativeAbstractBinding> m_selfPointer;
};

class QDeclarativeValueTypeProxyBinding : public QDeclarativeAbstractBinding
{
public:
    QDeclarativeValueTypeProxyBinding(QObject *o, int coreIndex);

    virtual Type bindingType() const { return ValueTypeProxy; }

    virtual void setEnabled(bool, QDeclarativePropertyPrivate::WriteFlags);
    virtual void update(QDeclarativePropertyPrivate::WriteFlags);

    QDeclarativeAbstractBinding *binding(int propertyIndex);

    void removeBindings(quint32 mask);

protected:
    ~QDeclarativeValueTypeProxyBinding();

private:
    void recursiveEnable(QDeclarativeAbstractBinding *, QDeclarativePropertyPrivate::WriteFlags);
    void recursiveDisable(QDeclarativeAbstractBinding *);

    friend class QDeclarativeAbstractBinding;
    QObject *m_object;
    int m_index;
    QDeclarativeAbstractBinding *m_bindings;
};

class QDeclarativeContext;
class QDeclarativeBindingPrivate;
class Q_DECLARATIVE_PRIVATE_EXPORT QDeclarativeBinding : public QDeclarativeExpression, public QDeclarativeAbstractBinding
{
Q_OBJECT
public:
    QDeclarativeBinding(const QString &, QObject *, QDeclarativeContext *, QObject *parent=0);
    QDeclarativeBinding(const QString &, QObject *, QDeclarativeContextData *, QObject *parent=0);
    QDeclarativeBinding(void *, QDeclarativeRefCount *, QObject *, QDeclarativeContextData *, 
                        const QString &, int, QObject *parent);

    void setTarget(const QDeclarativeProperty &);
    QDeclarativeProperty property() const;

    bool enabled() const;

    // Inherited from  QDeclarativeAbstractBinding
    virtual void setEnabled(bool, QDeclarativePropertyPrivate::WriteFlags flags);
    virtual void update(QDeclarativePropertyPrivate::WriteFlags flags);
    virtual QString expression() const;

public Q_SLOTS:
    void update() { update(QDeclarativePropertyPrivate::DontRemoveBinding); }

protected:
    ~QDeclarativeBinding();
    void emitValueChanged();

private:
    Q_DECLARE_PRIVATE(QDeclarativeBinding)
};

QT_END_NAMESPACE

Q_DECLARE_METATYPE(QDeclarativeBinding*)

#endif // QDECLARATIVEBINDING_P_H