qobject_binding.h

/* This file is part of the KDE libraries
    Copyright (C) 2005, 2006 Ian Reinhart Geiser <[email protected]>
    Copyright (C) 2005, 2006 Matt Broadstone <[email protected]>
    Copyright (C) 2005, 2006 Richard J. Moore <[email protected]>
    Copyright (C) 2005, 2006 Erik L. Bunce <[email protected]>
    Copyright (C) 2007, 2008 Sebastian Sauer <[email protected]>
 
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.
 
    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.
 
    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
    Boston, MA 02110-1301, USA.
*/
 
#ifndef QOBJECT_BINDING_H
#define QOBJECT_BINDING_H
 
#include <QObjectCleanupHandler>
#include <QDebug>
 
#include <kjs/function.h>
 
#include "binding_support.h"
#include "object_binding.h"
 
/**
* A simple pointer style method.
* This will extract the pointer, cast it to the native type and place it in "value".
* Any data that should be returned from this method should be placed into "result";
*
*/
#define START_QOBJECT_METHOD( METHODNAME, TYPE) \
    KJS::JSValue *METHODNAME( KJS::ExecState *exec, KJS::JSObject *self, const KJS::List &args ) \
    { \
        Q_UNUSED( args ); \
        KJS::JSValue *result = KJS::jsNull(); \
        KJSEmbed::QObjectBinding *imp = KJSEmbed::extractBindingImp<KJSEmbed::QObjectBinding>(exec, self ); \
        if( imp ) \
        { \
            TYPE *object = imp->qobject<TYPE>(); \
            if( object ) \
            {
 
/**
* End a variant method started by START_QOBJECT_METHOD
*/
#define END_QOBJECT_METHOD \
    } \
    else \
        KJS::throwError(exec, KJS::ReferenceError, QString("QO: The internal object died %1:%2.").arg(__FILE__).arg(__LINE__));\
    } \
    else \
        KJS::throwError(exec, KJS::ReferenceError, QString("QObject died."));\
    return result; \
    }
 
class QObject;
class QMetaMethod;
 
namespace KJSEmbed
{
 
KJS_BINDING(QObjectFactory)
 
class EventProxy;
 
class KJSEMBED_EXPORT QObjectBinding : public ObjectBinding
{
public:
 
    QObjectBinding(KJS::ExecState *exec, QObject *object);
    ~QObjectBinding() override;
 
    static void publishQObject(KJS::ExecState *exec, KJS::JSObject *target, QObject *object);
 
    /**
    * Enumeration of access-flags that could be OR-combined to define
    * what parts of the QObject should be published.
    * Default is AllSlots|AllSignals|AllProperties|AllObjects what
    * means that everything got published, even e.g. private slots.
    */
    enum Access {
        None = 0x00, ///< Don't publish anything.
 
        ScriptableSlots = 0x01, ///< Publish slots that have Q_SCRIPTABLE defined.
        NonScriptableSlots = 0x02, ///< Publish slots that don't have Q_SCRIPTABLE defined.
        PrivateSlots = 0x04, ///< Publish private slots.
        ProtectedSlots = 0x08, ///< Publish protected slots.
        PublicSlots = 0x10, ///< Publish public slots.
        AllSlots = ScriptableSlots | NonScriptableSlots | PrivateSlots | ProtectedSlots | PublicSlots,
 
        ScriptableSignals = 0x100, ///< Publish signals that have Q_SCRIPTABLE defined.
        NonScriptableSignals = 0x200, ///< Publish signals that don't have Q_SCRIPTABLE defined.
        PrivateSignals = 0x400, ///< Publish private signals.
        ProtectedSignals = 0x800, ///< Publish protected signals.
        PublicSignals = 0x1000, ///< Publish public signals.
        AllSignals = ScriptableSignals | NonScriptableSignals | PrivateSignals | ProtectedSignals | PublicSignals,
 
        ScriptableProperties = 0x10000, ///< Publish properties that have Q_SCRIPTABLE defined.
        NonScriptableProperties = 0x20000, ///< Publish properties that don't have Q_SCRIPTABLE defined.
        AllProperties = ScriptableProperties | NonScriptableProperties,
 
        GetParentObject = 0x100000, ///< Provide access to the parent QObject the QObject has.
        SetParentObject = 0x200000, ///< Be able to set the parent QObject the QObject has.
        ChildObjects = 0x400000, ///< Provide access to the child QObject's the QObject has.
        AllObjects = GetParentObject | SetParentObject | ChildObjects
    };
 
    Q_DECLARE_FLAGS(AccessFlags, Access)
 
    /**
    * \return the defined \a Access flags.
    */
    AccessFlags access() const;
 
    /**
    * Set the defined \a Access flags to \p access .
    */
    void setAccess(AccessFlags access);
 
    /**
    * Set the value \p value of the property \p propertyName .
    */
    void put(KJS::ExecState *exec, const KJS::Identifier &propertyName, KJS::JSValue *value,
             int attr = KJS::None) override;
    using JSObject::put;
 
    /**
    * \return true if the property \p propertyName can be changed else false is returned.
    */
    bool canPut(KJS::ExecState *exec, const KJS::Identifier &propertyName) const override;
 
    /**
    * Called to ask if we have a callback for the named property.
    * We return the callback in the property slot.
    */
    bool getOwnPropertySlot(KJS::ExecState *exec, const KJS::Identifier &propertyName,
                            KJS::PropertySlot &slot) override;
    using JSObject::getOwnPropertySlot;
 
    /**
    * Callback used to get properties.
    */
    static KJS::JSValue *propertyGetter(KJS::ExecState *exec, KJS::JSObject *, const KJS::Identifier &name, const KJS::PropertySlot &);
 
    /**
    * \return a string-representation of the QObject. For example for a QWidget-instance that
    * has the QObject::objectName "mywidget" the string "mywidget (QWidget)" is returned.
    */
    KJS::UString toString(KJS::ExecState *exec) const override;
 
    /**
    * \return the QObject's classname. For example for a QWidget-instance the string "QWidget"
    * is returned.
    */
    KJS::UString className() const override;
 
    /**
    * Add the QObject \p object to the internal QObjectCleanupHandler to watch the
    * lifetime of the QObject to know when the QObject got deleted.
    */
    void watchObject(QObject *object);
 
    /**
     * \return the internal object as a pointer to type T to the
     * internal object that is derived from QObject.
     */
    template <typename T>
    T *qobject() const
    {
        QObject *object = QObjectBinding::object<QObject>();
        if (object) {
            return qobject_cast<T *>(object);
        } else {
            return nullptr;
        }
    }
 
private:
    EventProxy *m_evproxy;
    QObjectCleanupHandler *m_cleanupHandler;
    AccessFlags m_access;
};
 
Q_DECLARE_OPERATORS_FOR_FLAGS(QObjectBinding::AccessFlags)
 
class KJSEMBED_EXPORT SlotBinding : public KJS::InternalFunctionImp
{
public:
    SlotBinding(KJS::ExecState *exec, const QMetaMethod &memberName);
    KJS::JSValue *callAsFunction(KJS::ExecState *exec, KJS::JSObject *self, const KJS::List &args) override;
    bool implementsCall() const override
    {
        return true;
    }
    bool implementsConstruct() const override
    {
        return false;
    }
 
protected:
    QByteArray m_memberName;
};
 
/**
* Returns a binding object for the specified QObject. This method walks
* up the meta objects in order to find the most specific binding it can.
* There should always be some kind of binding possible even if it is just
* the QObject binding.
*
* \param exec Represents the current state of script execution.
* \param value The QObject or from it inherited instance we should return
* a binding object for.
* \param owner Defines who's the owner of the QObject. This could be;
*     \li CPPOwned what means, that the QObject's lifetime is handled
*         within C++ code. So, we just provide access to it and don't
*         take any future actions.
*     \li QObjOwned means that the QObject got deleted if the parent QObject
*         is destroyed. If the QObject has no parent QObject, it behaves like
*         JSOwned.
*     \li JSOwned means, that the returned KJS::JSObject takes care of
*         deleting the QObject. This means, that the QObject got deleted
*         as soon as the KJS::JSObject got destroyed what happens if the
*         KJS::JSObject is not needed / in use any longer.
* \return the binding object instance that wraps the QObject instance or
* a JSObject with a prototype of jsNull (that is, the ECMAScript "null" value,
* not a null object pointer) if we failed to provide any binding for it.
*/
KJSEMBED_EXPORT KJS::JSObject *createQObject(KJS::ExecState *exec, QObject *value, KJSEmbed::ObjectBinding::Ownership owner = KJSEmbed::ObjectBinding::JSOwned);
 
}
#endif