MemCore::LoaderRegistry< X > Class Template Reference

Database for routines that may create objects of type X. More...

#include <elementary/memcore/Loader.hpp>

Inheritance diagram for MemCore::LoaderRegistry< X >:

Static Public Member Functions
static void	getSupportedExtensions (list< string > &SupportedExtensions)
	Extend the given list of possible extensions.
static bool	isloadable (const RefPtr< LoaderParameters > &LP)
	Check whether some loader parameters might be handable here.
static RefPtr< X >	load (bool &success, const RefPtr< LoaderParameters > &LP, const RefPtr< X > &xptr=NullPtr())
	Actually load some object from the input source.
static RefPtr< LoaderRequest >	request (const RefPtr< LoaderParameters > &LP, const RefPtr< X > &xptr=NullPtr())
	Actually load some object from the input source.

Additional Inherited Members
Static Protected Member Functions inherited from MemCore::LoaderRegistryBase
static void	domain_append (const type_info &id, const RefPtr< LoaderBase > &ldr, const type_info &Domain)

Detailed Description

template<class X>
class MemCore::LoaderRegistry< X >

Database for routines that may create objects of type X.

The LoaderRegistry class allows to actually create objects of type X from a certain input source. The input source is specified through the LoaderParameters class, which may carry arbitrary additional interfaces.

bool success;
RefPtr<LoaderParameters> LP = new LoaderParameters("FileName.txt");
 
        LP->addInterface( new ProgressDisplay() );
 
RefPtr<X> object = LoaderRegistry<X>::load(success, LP);

    Implementation of a new Loader:
    Consider a type Bundle to be created from some input source.
    We introduce an artificial type, here called HDF5

struct  HDF5 {};

with no other purpose as to provide a unique typeid in C++. We implement a loader by deriving from the Loader<Bundle> base class:

struct  myHDF5Loader : Loader<Bundle>
{
        RefPtr<Bundle> load(const RefPtr<LoaderParameters>&, const RefPtr<Bundle>&Xptr = NullPtr() )
        {}
} override;

The name of this class is not of relevance. We now add an instance of this loader to the LoaderRegistry for the Bundle type:

MemCore::LoaderRegistry<Bundle>::append( typeid(HDF5), new myHDF5Loader() );

Now we have the means to iterate over all loaders which have been registered for the type Bundle. This iteration is implemented in function LoaderRegistryBase::domain_load() as a static function, or easier as LoaderRegistry<Bundle>::load();