You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
273 lines
10 KiB
273 lines
10 KiB
/*
|
|
* The Type2Type template and the Inheritance Detector are from
|
|
* <http://www.cuj.com/experts/1810/alexandr.htm>
|
|
* (c) Andrei Alexandrescu <andrei@metalanguage.com> and
|
|
* free for any use.
|
|
*
|
|
* The rest is:
|
|
* Copyright (C) 2001 Simon Hausmann <hausmann@kde.org>
|
|
*
|
|
* 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.
|
|
*/
|
|
// -*- mode: c++ -*-
|
|
//
|
|
// W A R N I N G
|
|
// -------------
|
|
//
|
|
// This file is not part of the KDE API. It exists for the convenience
|
|
// of KGenericFactory. This header file may change from version to
|
|
// version without notice, or even be removed.
|
|
//
|
|
// We mean it.
|
|
//
|
|
|
|
#ifndef KGENERICFACTORY_TCC
|
|
#define KGENERICFACTORY_TCC
|
|
|
|
#include <tqmetaobject.h>
|
|
#include <ktypelist.h>
|
|
|
|
namespace KParts
|
|
{
|
|
class Part;
|
|
}
|
|
|
|
namespace KDEPrivate
|
|
{
|
|
template <class Base>
|
|
struct InheritanceDetector
|
|
{
|
|
typedef char ConversionExists;
|
|
struct ConversionDoesNotExist { char bleh[ 2 ]; };
|
|
static ConversionExists test( Base * );
|
|
static ConversionDoesNotExist test( ... );
|
|
};
|
|
|
|
/* Simon: KCC doesn't eat the generic InheritanceDetector<Base>.
|
|
Instead we have to use concrete specializations :-(
|
|
|
|
template <class Base, class Derived>
|
|
struct InheritanceTest
|
|
{
|
|
typedef Derived * DerivedPtr;
|
|
enum { Result = sizeof( InheritanceDetector<Base>::test( DerivedPtr() ) ) ==
|
|
sizeof( InheritanceDetector<Base>::ConversionExists ) };
|
|
};
|
|
*/
|
|
|
|
template <class Derived>
|
|
struct TQWidgetInheritanceTest
|
|
{
|
|
typedef Derived * DerivedPtr;
|
|
enum { Result = sizeof( InheritanceDetector<TQWidget>::test( DerivedPtr() ) ) ==
|
|
sizeof( InheritanceDetector<TQWidget>::ConversionExists ) };
|
|
};
|
|
|
|
template <class Derived>
|
|
struct PartInheritanceTest
|
|
{
|
|
typedef Derived * DerivedPtr;
|
|
enum { Result = sizeof( InheritanceDetector<KParts::Part>::test( DerivedPtr() ) ) ==
|
|
sizeof( InheritanceDetector<KParts::Part>::ConversionExists ) };
|
|
};
|
|
|
|
|
|
template <bool condition, typename Then, typename Else>
|
|
struct If
|
|
{
|
|
typedef Else Result;
|
|
};
|
|
|
|
template <typename Then, typename Else>
|
|
struct If<true, Then, Else>
|
|
{
|
|
typedef Then Result;
|
|
};
|
|
|
|
// a small helper template, to ease the overloading done in ConcreteFactory
|
|
// to choose the right constructor for the given class.
|
|
template <class T>
|
|
struct Type2Type
|
|
{
|
|
typedef T OriginalType;
|
|
};
|
|
|
|
// this template is called from the MultiFactory one. It instantiates
|
|
// the given class if the className matches. Instantiating is done by
|
|
// calling the right constructor (a parentwidget/widgetname/parent/name
|
|
// one for Parts, a parentwidget/widgetname one for widgets and last
|
|
// but not least the standard default constructor of parent/name .
|
|
// the choice of the right constructor is done using an ordered inheritance
|
|
// test.
|
|
template <class Product, class ParentType = TQObject>
|
|
class ConcreteFactory
|
|
{
|
|
public:
|
|
typedef typename If< PartInheritanceTest< Product >::Result,
|
|
KParts::Part,
|
|
typename If< TQWidgetInheritanceTest< Product >::Result,
|
|
TQWidget, TQObject >::Result >::Result BaseType;
|
|
|
|
static inline Product *create( TQWidget *parentWidget, const char *widgetName,
|
|
TQObject *parent, const char *name,
|
|
const char *className, const TQStringList &args )
|
|
{
|
|
TQMetaObject *tqmetaObject = Product::tqstaticMetaObject();
|
|
while ( tqmetaObject )
|
|
{
|
|
if ( !qstrcmp( className, tqmetaObject->className() ) )
|
|
return create( parentWidget, widgetName,
|
|
parent, name, args, Type2Type<BaseType>() );
|
|
tqmetaObject = tqmetaObject->tqsuperClass();
|
|
}
|
|
return 0;
|
|
}
|
|
private:
|
|
typedef typename If< TQWidgetInheritanceTest<ParentType>::Result,
|
|
ParentType, TQWidget >::Result WidgetParentType;
|
|
|
|
static inline Product *create( TQWidget *parentWidget, const char *widgetName,
|
|
TQObject *parent, const char *name,
|
|
const TQStringList &args, Type2Type<KParts::Part> )
|
|
{
|
|
return new Product( parentWidget, widgetName, parent, name, args );
|
|
}
|
|
|
|
static inline Product *create( TQWidget* /*parentWidget*/, const char* /*widgetName*/,
|
|
TQObject *parent, const char *name,
|
|
const TQStringList &args, Type2Type<TQWidget> )
|
|
{
|
|
|
|
WidgetParentType *p = dynamic_cast<WidgetParentType *>( static_cast<TQT_BASE_OBJECT_NAME*>(parent) );
|
|
if ( parent && !p )
|
|
return 0;
|
|
return new Product( p, name, args );
|
|
}
|
|
|
|
static inline Product *create( TQWidget* /*parentWidget*/, const char* /*widgetName*/,
|
|
TQObject *parent, const char *name,
|
|
const TQStringList &args, Type2Type<TQObject> )
|
|
{
|
|
ParentType *p = dynamic_cast<ParentType *>( static_cast<TQT_BASE_OBJECT_NAME*>(parent) );
|
|
if ( parent && !p )
|
|
return 0;
|
|
return new Product( p, name, args );
|
|
}
|
|
};
|
|
|
|
// this template is used to iterate through the typelist and call the
|
|
// concrete factory for each type. the specializations of this template
|
|
// are the ones actually being responsible for iterating, in fact.
|
|
template <class Product, class ParentType = TQObject>
|
|
class MultiFactory
|
|
{
|
|
public:
|
|
inline static TQObject *create( TQWidget *parentWidget, const char *widgetName,
|
|
TQObject *parent, const char *name,
|
|
const char *className,
|
|
const TQStringList &args )
|
|
{
|
|
return static_cast<TQObject*>(static_cast<QObject*>(ConcreteFactory<Product, ParentType>::create( parentWidget, widgetName,
|
|
parent, name, className,
|
|
args )));
|
|
}
|
|
|
|
};
|
|
|
|
// this specialized template we 'reach' at the end of a typelist
|
|
// (the last item in a typelist is the NullType)
|
|
template <>
|
|
class MultiFactory<KDE::NullType>
|
|
{
|
|
public:
|
|
inline static TQObject *create( TQWidget *, const char *, TQObject *,
|
|
const char *, const char *,
|
|
const TQStringList & )
|
|
{ return 0; }
|
|
};
|
|
|
|
// this specialized template we 'reach' at the end of a typelist
|
|
// (the last item in a typelist is the NullType)
|
|
template <>
|
|
class MultiFactory<KDE::NullType, KDE::NullType>
|
|
{
|
|
public:
|
|
inline static TQObject *create( TQWidget *, const char *, TQObject *,
|
|
const char *, const char *,
|
|
const TQStringList & )
|
|
{ return 0; }
|
|
};
|
|
|
|
template <class Product, class ProductListTail>
|
|
class MultiFactory< KTypeList<Product, ProductListTail>, TQObject >
|
|
{
|
|
public:
|
|
inline static TQObject *create( TQWidget *parentWidget, const char *widgetName,
|
|
TQObject *parent, const char *name,
|
|
const char *className,
|
|
const TQStringList &args )
|
|
{
|
|
// try with the head of the typelist first. the head is always
|
|
// a concrete type.
|
|
TQObject *object = MultiFactory<Product>::create( parentWidget, widgetName,
|
|
parent, name, className,
|
|
args );
|
|
|
|
if ( !object )
|
|
object = MultiFactory<ProductListTail>::create( parentWidget, widgetName,
|
|
parent, name, className,
|
|
args );
|
|
|
|
return object;
|
|
}
|
|
};
|
|
|
|
template <class Product, class ProductListTail,
|
|
class ParentType, class ParentTypeListTail>
|
|
class MultiFactory< KTypeList<Product, ProductListTail>,
|
|
KTypeList<ParentType, ParentTypeListTail> >
|
|
{
|
|
public:
|
|
inline static TQObject *create( TQWidget *parentWidget, const char *widgetName,
|
|
TQObject *parent, const char *name,
|
|
const char *className,
|
|
const TQStringList &args )
|
|
{
|
|
// try with the head of the typelist first. the head is always
|
|
// a concrete type.
|
|
TQObject *object = MultiFactory<Product, ParentType>
|
|
::create( parentWidget, widgetName,
|
|
parent, name, className, args );
|
|
|
|
// if that failed continue by advancing the typelist, calling this
|
|
// template specialization recursively (with T2 being a typelist) .
|
|
// at the end we reach the nulltype specialization.
|
|
if ( !object )
|
|
object = MultiFactory<ProductListTail, ParentTypeListTail>
|
|
::create( parentWidget, widgetName,
|
|
parent, name, className, args );
|
|
|
|
return object;
|
|
}
|
|
};
|
|
}
|
|
|
|
#endif
|
|
|
|
/*
|
|
* vim: et sw=4
|
|
*/
|