The KLibLoader allows you to load libraries dynamically at runtime. More...

#include <KLibLoader>

Inheritance diagram for KLibLoader:

Public Types
enum	ComponentLoadingError { ErrNoLibrary = 1, ErrNoFactory, ErrNoComponent, ErrServiceProvidesNoLibrary, ErrNoServiceFound }
Public Member Functions
KPluginFactory *	factory (const QString &libname, QLibrary::LoadHints loadHint=0)
QString	lastErrorMessage () const
KLibrary *	library (const QString &libname, QLibrary::LoadHints loadHint=0)
void	unloadLibrary (const QString &libname)
Static Public Member Functions
template<typename T >
static T *	createInstance (const QString &keyword, const QString &libname, QObject parent=0, const QVariantList &args=QVariantList(), int error=0)
template<typename T >
static T *	createInstance (const QString &libname, QObject parent=0, const QVariantList &args=QVariantList(), int error=0)
template<typename T >
static T *	createInstance (const QString &libname, QObject parent, const QStringList &args, int error=0)
static QString	errorString (int componentLoadingError)
static QString	findLibrary (const QString &libname, const KComponentData &cData=KGlobal::mainComponent())
static KLibLoader *	self ()

Detailed Description

The KLibLoader allows you to load libraries dynamically at runtime.

Dependent libraries are loaded automatically.

KLibLoader follows the singleton pattern. You can not create multiple instances. Use self() to get a pointer to the loader.

Deprecated:

You have two other possibilites:

KPluginLoader or KService::createInstance for plugins
KLibrary for other libraries

See also:: KLibrary; KPluginLoader

Author:: Torben Weis <weis@kde.org>

Definition at line 55 of file klibloader.h.

Member Enumeration Documentation

enum KLibLoader::ComponentLoadingError

This enum type defines the possible error cases that can happen when loading a component.

Use errorString() to convert the error code to a human-readable string

Enumerator:

ErrNoLibrary
ErrNoFactory
ErrNoComponent
ErrServiceProvidesNoLibrary
ErrNoServiceFound

Definition at line 165 of file klibloader.h.

Member Function Documentation

template<typename T >

static T* KLibLoader::createInstance	(	const QString &	keyword,
		const QString &	libname,
		QObject *	parent = `0`,
		const QVariantList &	args = `QVariantList()`,
		int *	error = `0`
	)		`[inline, static]`

This template allows to load the specified library and ask the factory to create an instance of the given template type.

Parameters:

keyword	the keyword for the plugin - see KPluginFactory::registerPlugin()
libname	the library to open
parent	the parent object (see QObject constructor)
args	a list of string arguments, passed to the factory and possibly to the component (see KPluginFactory)
error	if not null, the int will be set to 0 on success or one of the error codes defined by ComponentLoadingError if there was an error

Returns:: a pointer to the newly created object or a null pointer if the factory was unable to create an object of the given type

Deprecated:: Use KService::createInstance() or KPluginFactory instead

Definition at line 202 of file klibloader.h.

template<typename T >

static T* KLibLoader::createInstance	(	const QString &	libname,
		QObject *	parent = `0`,
		const QVariantList &	args = `QVariantList()`,
		int *	error = `0`
	)		`[inline, static]`

This template allows to load the specified library and ask the factory to create an instance of the given template type.

Parameters:

libname	the library to open
parent	the parent object (see QObject constructor)
args	a list of string arguments, passed to the factory and possibly to the component (see KPluginFactory)
error	if not null, the int will be set to 0 on success or one of the error codes defined by ComponentLoadingError if there was an error

Returns:: a pointer to the newly created object or a null pointer if the factory was unable to create an object of the given type

Deprecated:: Use KService::createInstance() or KPluginFactory instead

Definition at line 248 of file klibloader.h.

template<typename T >

static T* KLibLoader::createInstance	(	const QString &	libname,
		QObject *	parent,
		const QStringList &	args,
		int *	error = `0`
	)		`[inline, static]`

Deprecated:: Use one of the other createInstance methods or KPluginLoader or KService::createInstance instead

Definition at line 260 of file klibloader.h.

QString KLibLoader::errorString ( int componentLoadingError ) [static]

Converts a numerical error code into a human-readable error message.

Parameters:

componentLoadingError the error code, as set using the error parameter of createInstance()

Returns:: the translated error message describing the error represented by componentLoadingError

See also:: ComponentLoadingError

Definition at line 142 of file klibloader.cpp.

KPluginFactory * KLibLoader::factory	(	const QString &	libname,
		QLibrary::LoadHints	loadHint = `0`
	)

Loads and initializes a library.

Loading a library multiple times is handled gracefully.

This is a convenience function that returns the factory immediately

Parameters:

libname This is the library name without extension. Usually that is something like "libkspread". The function will then search for a file named "libkspread.la" in the KDE library paths. The *.la files are created by libtool and contain important information especially about the libraries dependencies on other shared libs. Loading a "libfoo.so" could not solve the dependencies problem.

You can, however, give a library name ending in ".so" (or whatever is used on your platform), and the library will be loaded without resolving dependencies. Use with caution.

Parameters:

loadHint provides more control over how the library is loaded

Returns:: the KPluginFactory, or 0 if the library does not exist or it does not have a factory

See also:: library

Definition at line 127 of file klibloader.cpp.

QString KLibLoader::findLibrary	(	const QString &	libname,
		const KComponentData &	cData = `KGlobal::mainComponent()`
	)		`[static]`

Helper method which looks for a library in the standard paths ("module" and "lib" resources).

Made public for code that doesn't use KLibLoader itself, but still wants to open modules.

Parameters:

libname	of the library. If it is not a path, the function searches in the "module" and "lib" resources. If there is no extension, ".la" will be appended.
cData	a KComponentData used to get the standard paths

Returns:: the name of the library if it was found, an empty string otherwise

Definition at line 84 of file klibloader.cpp.

QString KLibLoader::lastErrorMessage ( ) const

Returns an error message that can be useful to debug the problem.

Returns QString() if the last call to library() was successful. You can call this function more than once. The error message is only reset by a new call to library().

Returns:: the last error message, or QString() if there was no error

Definition at line 118 of file klibloader.cpp.

KLibrary * KLibLoader::library	(	const QString &	libname,
		QLibrary::LoadHints	loadHint = `0`
	)

Loads and initializes a library.

Loading a library multiple times is handled gracefully.

Parameters:

libname This is the library name without extension. Usually that is something like "libkspread". The function will then search for a file named "libkspread.la" in the KDE library paths. The *.la files are created by libtool and contain important information especially about the libraries dependencies on other shared libs. Loading a "libfoo.so" could not solve the dependencies problem.

You can, however, give a library name ending in ".so" (or whatever is used on your platform), and the library will be loaded without resolving dependencies. Use with caution.

Parameters:

loadHint provides more control over how the library is loaded

Returns:: KLibrary is invalid (0) when the library couldn't be dlopened. in such a case you can retrieve the error message by calling KLibLoader::lastErrorMessage()

See also:: factory

Definition at line 89 of file klibloader.cpp.

KLibLoader * KLibLoader::self ( ) [static]

Returns a pointer to the factory.

Use this function to get an instance of KLibLoader.

Returns:: a pointer to the loader. If no loader exists until now then one is created.

Deprecated:: use KPluginLoader instead

Definition at line 46 of file klibloader.cpp.

void KLibLoader::unloadLibrary ( const QString & libname )

Unloads the library with the given name.

Parameters:

libname This is the library name without extension. Usually that is something like "libkspread". The function will then search for a file named "libkspread.la" in the KDE library paths. The *.la files are created by libtool and contain important information especially about the libraries dependencies on other shared libs. Loading a "libfoo.so" could not solve the dependencies problem.

You can, however, give a library name ending in ".so" (or whatever is used on your platform), and the library will be loaded without resolving dependencies. Use with caution.

Definition at line 123 of file klibloader.cpp.

The documentation for this class was generated from the following files:

KDECore

KLibLoader Class Reference

Public Types

Public Member Functions

Static Public Member Functions

Detailed Description

Member Enumeration Documentation

Member Function Documentation

KDECore

kdelibs