Source: componentfactory.h
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#ifndef __kparts_componentfactory_h__
#define __kparts_componentfactory_h__
#include
#include
#include
namespace KParts
{
// this is a namespace and not a class because stupid egcs 1.1.2 doesn't grok
// static template methods in classes. !@%@#$!
namespace ComponentFactory
{
/**
* This enum type defines the possible error cases that can happen
* when loading a component.
*
*
* ErrNoServiceFound - no service implementing the
* given mimetype and fullfilling the given constraint expression
* can be found.ErrServiceProvidesNoLibrary - the specified service
* provides no shared libraryErrNoLibrary - the specified library could not be
* loaded. Use KLibLoader::lastErrorMessage for details.ErrNoFactory - the library does not export a factory
* for creating componentsErrNoComponent - the factory does not support creating
* components of the specified type
*/
enum ComponentLoadingError { ErrNoServiceFound = 1,
ErrServiceProvidesNoLibrary,
ErrNoLibrary,
ErrNoFactory,
ErrNoComponent };
/**
* This template function allows to ask the given factory to create an
* instance of the given template type.
*
* Example of usage:
*
* MyPlugin *plugin = KParts::ComponentFactory::createInstance<MyPlugin>( factory, parent );
*
*
* @param factory The factory to ask for the creation of the component
* @param parent The parent object (see QObject constructor)
* @param name The name of the object to create (see QObject constructor)
* @param args A list of string arguments, passed to the factory and possibly
* to the component (see KLibFactory)
* @return A pointer to the newly created object or a null pointer if the
* factory was unable to create an object of the given type.
*/
template
static T *createInstanceFromFactory( KLibFactory *factory, QObject *parent = 0,
const char *name = 0,
const QStringList &args = QStringList() )
{
QObject *object = factory->create( parent, name,
T::staticMetaObject()->className(),
args );
T *result = dynamic_cast( object );
if ( !result )
delete object;
return result;
}
/**
* This template function allows to ask the given kparts factory to create an
* instance of the given template type.
*
* Example of usage:
*
* KViewPart *doc = KParts::ComponentFactory::createInstance<KViewPart>( factory, parent );
*
*
* @param factory The factory to ask for the creation of the component
* @param parentWidget the parent widget for the part
* @param widgetName the name of the part's widget
* @param parent The parent object (see QObject constructor)
* @param name The name of the object to create (see QObject constructor)
* @param args A list of string arguments, passed to the factory and possibly
* to the component (see KLibFactory)
* @return A pointer to the newly created object or a null pointer if the
* factory was unable to create an object of the given type.
*/
template
static T *createPartInstanceFromFactory( KParts::Factory *factory,
QWidget *parentWidget = 0,
const char *widgetName = 0,
QObject *parent = 0,
const char *name = 0,
const QStringList &args = QStringList() )
{
KParts::Part *object = factory->createPart( parentWidget, widgetName,
parent, name,
T::staticMetaObject()->className(),
args );
T *result = dynamic_cast( object );
if ( !result )
delete object;
return result;
}
/**
* This template allows to load the specified library and ask the
* factory to create an instance of the given template type.
*
* @param libraryName The library to open
* @param parent The parent object (see QObject constructor)
* @param name The name of the object to create (see QObject constructor)
* @param args A list of string arguments, passed to the factory and possibly
* to the component (see KLibFactory)
* @param error
* @return A pointer to the newly created object or a null pointer if the
* factory was unable to create an object of the given type.
*/
template
static T *createInstanceFromLibrary( const char *libraryName, QObject *parent = 0,
const char *name = 0,
const QStringList &args = QStringList(),
int *error = 0 )
{
KLibrary *library = KLibLoader::self()->library( libraryName );
if ( !library )
{
if ( error )
*error = ErrNoLibrary;
return 0;
}
KLibFactory *factory = library->factory();
if ( !factory )
{
library->unload();
if ( error )
*error = ErrNoFactory;
return 0;
}
T *res = createInstanceFromFactory( factory, parent, name, args );
if ( !res )
{
library->unload();
if ( error )
*error = ErrNoComponent;
}
return res;
}
template
static T *createPartInstanceFromLibrary( const char *libraryName,
QWidget *parentWidget = 0,
const char *widgetName = 0,
QObject *parent = 0,
const char *name = 0,
const QStringList &args = QStringList(),
int *error = 0 )
{
KLibrary *library = KLibLoader::self()->library( libraryName );
if ( !library )
{
if ( error )
*error = ErrNoLibrary;
return 0;
}
KLibFactory *factory = library->factory();
if ( !factory )
{
library->unload();
if ( error )
*error = ErrNoFactory;
return 0;
}
KParts::Factory *partFactory = dynamic_cast( factory );
if ( !partFactory )
{
library->unload();
if ( error )
*error = ErrNoFactory;
return 0;
}
T *res = createPartInstanceFromFactory( partFactory, parentWidget,
widgetName, parent, name, args );
if ( !res )
{
library->unload();
if ( error )
*error = ErrNoComponent;
}
return res;
}
template
static T *createInstanceFromService( const KService::Ptr &service,
QObject *parent = 0,
const char *name = 0,
const QStringList &args = QStringList(),
int *error = 0 )
{
QString library = service->library();
if ( library.isEmpty() )
{
if ( error )
*error = ErrServiceProvidesNoLibrary;
return 0;
}
return createInstanceFromLibrary( library.local8Bit().data(), parent,
name, args, error );
}
template
static T *createPartInstanceFromService( const KService::Ptr &service,
QWidget *parentWidget = 0,
const char *widgetName = 0,
QObject *parent = 0,
const char *name = 0,
const QStringList &args = QStringList(),
int *error = 0 )
{
QString library = service->library();
if ( library.isEmpty() )
{
if ( error )
*error = ErrServiceProvidesNoLibrary;
return 0;
}
return createPartInstanceFromLibrary( library.local8Bit(), parentWidget,
widgetName, parent, name, args, error );
}
template
static T *createInstanceFromServices( ServiceIterator begin, ServiceIterator end,
QObject *parent = 0,
const char *name = 0,
const QStringList &args = QStringList(),
int *error = 0 )
{
for (; begin != end; ++begin )
{
KService::Ptr service = *begin;
if ( error )
*error = 0;
T *component = createInstanceFromService( service, parent, name,
args, error );
if ( component )
return component;
}
if ( error )
*error = ErrNoServiceFound;
return 0;
}
template
static T *createPartInstanceFromServices( ServiceIterator begin,
ServiceIterator end,
QWidget *parentWidget = 0,
const char *widgetName = 0,
QObject *parent = 0,
const char *name = 0,
const QStringList &args = QStringList(),
int *error = 0 )
{
for (; begin != end; ++begin )
{
KService::Ptr service = *begin;
if ( error )
*error = 0;
T *component = createPartInstanceFromService( service, parentWidget,
widgetName, parent,
name, args, error );
if ( component )
return component;
}
if ( error )
*error = ErrNoServiceFound;
return 0;
}
template
static T *createInstanceFromQuery( const QString &serviceType,
const QString &constraint = QString::null,
QObject *parent = 0,
const char *name = 0,
const QStringList &args = QStringList(),
int *error = 0 )
{
KTrader::OfferList offers = KTrader::self()->query( serviceType, constraint );
if ( offers.isEmpty() )
{
if ( error )
*error = ErrNoServiceFound;
return 0;
}
return createInstanceFromServices( offers.begin(),
offers.end(),
parent, name, args, error );
}
/**
* This method creates and returns a KParts part from a serviceType (e.g. a mimetype).
*
* You can use this method to create a generic viewer - that can display any
* kind of file, provided that there is a ReadOnlyPart installed for it - in 5 lines:
*
* // Given the following: KURL url, QWidget* parentWidget and QObject* parentObject.
* QString mimetype = KMimeType::findByURL( url )->name();
* KParts::ReadOnlyPart* part = KParts::ComponentFactory::createPartInstanceFromQuery( mimetype, QString::null, parentWidget, 0, parentObject, 0 );
* if ( part ) {
* part->openURL( url );
* part->widget()->show(); // also insert the widget into a layout, or simply use a QVBox as parentWidget
* }
*
*
* @param serviceType the type of service for which to find a part, e.g. a mimetype
* @param constraint an optionnal constraint to pass to the trader (see KTrader)
* @param parentWidget the parent widget, will be set as the parent of the part's widget
* @param widgetName the name that will be given to the part's widget
* @param parent the parent object for the part itself
* @param name the name that will be given to the part
* @param args A list of string arguments, passed to the factory and possibly
* to the component (see KLibFactory)
* @param error The int passed here will receive an error code in case of errors.
* (See enum ComponentLoadingError)
* @return A pointer to the newly created object or a null pointer if the
* factory was unable to create an object of the given type.
*/
template
static T *createPartInstanceFromQuery( const QString &serviceType,
const QString &constraint,
QWidget *parentWidget = 0,
const char *widgetName = 0,
QObject *parent = 0,
const char *name = 0,
const QStringList &args = QStringList(),
int *error = 0 )
{
KTrader::OfferList offers = KTrader::self()->query( serviceType, "KParts/ReadOnlyPart", constraint, QString::null );
if ( offers.isEmpty() )
{
if ( error )
*error = ErrNoServiceFound;
return 0;
}
return createPartInstanceFromServices( offers.begin(), offers.end(),
parentWidget, widgetName,
parent, name, args, error );
}
}
};
/*
* vim: et sw=4
*/
#endif
| Generated by: dfaure on faure on Tue Apr 16 08:50:22 2002, using kdoc 2.0a53. |