QPluginLoader 构建插件系统 基本控件（二十六）

一、说明
当我们的程序逐渐变大时，我们可能就会考虑功能插件化，或者支持某些模块动态加载和卸载。
二、代码
1.插件系统软件框架

2.homeFrameMenuBarInterface.h

#ifndef HOMEFRAMEMENUBARINTERFACE_H
#define HOMEFRAMEMENUBARINTERFACE_H

#include <QWidget>
#include "menuBarInterface.h"

class homeFrameMenuBarInterface : public QObject,public menuBarInterface
{
    Q_OBJECT
public:
    explicit homeFrameMenuBarInterface(QObject *parent = nullptr);

    Q_INTERFACES(menuBarInterface)
    Q_PLUGIN_METADATA(IID "org.qt-project.Qt.homeFrameMenuBarInterface" FILE "homeFrameMenuBarInterface.json")

    QWidget* create();
};

#endif // HOMEFRAMEMENUBARINTERFACE_H

3.menuBarInterface.h

#ifndef MENUBARINTERFACE_H
#define MENUBARINTERFACE_H
#include <QObject>
class menuBarInterface
{
public:
    virtual ~menuBarInterface(){}
    virtual QWidget* create() = 0;
};
Q_DECLARE_INTERFACE(menuBarInterface, "org.qt-project.Qt.menuBarInterface");

#endif // MENUBARINTERFACE_H

4.homePage.cpp

void homePage::loadPlguins()
{
    QDir dir;
    dir.setPath(QCoreApplication::applicationDirPath());
    foreach (QString fileName, dir.entryList(QDir::Files)){
        QPluginLoader pluginLoader(dir.absoluteFilePath(fileName));
        QObject *plugin = pluginLoader.instance();
        if (plugin){
            if(QString(plugin->metaObject()->className()) == "homeFrameMenuBarInterface"){
                menuBarInterface *interface = qobject_cast<menuBarInterface *>(plugin);
                if(interface){
                    m_pHomePageMenuBar = interface->create();
                }
            }
        }
    }
}

5.homeFrameMenuBarInterface.pro

QT += core gui

TEMPLATE = lib
CONFIG += plugin

CONFIG += c++11
greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

# The following define makes your compiler emit warnings if you use
# any Qt feature that has been marked deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS

# You can also make your code fail to compile if it uses deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0

SOURCES += \
    homeframemenubarinterface.cpp \
    menubar.cpp

HEADERS += \
    homeframemenubarinterface.h \
    menuBarInterface.h \
    menubar.h

DISTFILES += homeFrameMenuBar.json

# Default rules for deployment.
unix {
    target.path = $$[QT_INSTALL_PLUGINS]/generic
}
!isEmpty(target.path): INSTALLS += target


CONFIG(debug, debug|release){
    DLLDESTDIR = ../../../Target/debug
    TARGET = $$join(TARGET,,,d)
}
CONFIG(release, debug|release){
    DLLDESTDIR = ../../../Target/release
}

三、效果图