source: trunk/src/corelib/plugin/qpluginloader.cpp@ 552

Last change on this file since 552 was 2, checked in by Dmitry A. Kuminov, 16 years ago

Initially imported qt-all-opensource-src-4.5.1 from Trolltech.

File size: 11.7 KB
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41
42#include "qplatformdefs.h"
43
44#include "qplugin.h"
45#include "qpluginloader.h"
46#include <qfileinfo.h>
47#include "qlibrary_p.h"
48#include "qdebug.h"
49
50#ifndef QT_NO_LIBRARY
51
52QT_BEGIN_NAMESPACE
53
54/*!
55 \class QPluginLoader
56 \reentrant
57 \brief The QPluginLoader class loads a plugin at run-time.
58
59 \mainclass
60 \ingroup plugins
61
62 QPluginLoader provides access to a \l{How to Create Qt
63 Plugins}{Qt plugin}. A Qt plugin is stored in a shared library (a
64 DLL) and offers these benefits over shared libraries accessed
65 using QLibrary:
66
67 \list
68 \o QPluginLoader checks that a plugin is linked against the same
69 version of Qt as the application.
70 \o QPluginLoader provides direct access to a root component object
71 (instance()), instead of forcing you to resolve a C function manually.
72 \endlist
73
74 An instance of a QPluginLoader object operates on a single shared
75 library file, which we call a plugin. It provides access to the
76 functionality in the plugin in a platform-independent way. To
77 specify which plugin to load, either pass a file name in
78 the constructor or set it with setFileName().
79
80 The most important functions are load() to dynamically load the
81 plugin file, isLoaded() to check whether loading was successful,
82 and instance() to access the root component in the plugin. The
83 instance() function implicitly tries to load the plugin if it has
84 not been loaded yet. Multiple instances of QPluginLoader can be
85 used to access the same physical plugin.
86
87 Once loaded, plugins remain in memory until all instances of
88 QPluginLoader has been unloaded, or until the application