Qt 使用插件（Plugins）扩展应用程序简单示例Demo

#include "widget.h" #include "ui_widget.h" #include <QtWidgets> Widget::Widget(QWidget *parent) : QWidget(parent), ui(new Ui::Widget) { ui->setupUi(this); if(!loadPlugin()){ QMessageBox::warning(this, "Error", "Could not load the plugin"); } } Widget::~Widget() { delete ui; } void Widget::on_pushButton_clicked() { int a = ui->lineEdit_a->text().toInt(); int b = ui->lineEdit_b->text().toInt(); int r = -1; if(m_pInterface) r = m_pInterface->add(a,b); ui->lineEdit_r->setText(QString::number(r)); } bool Widget::loadPlugin() { QDir pluginsDir(qApp->applicationDirPath()); #if defined(Q_OS_WIN) if (pluginsDir.dirName().toLower() == "debug" || pluginsDir.dirName().toLower() == "release") pluginsDir.cdUp(); #elif defined(Q_OS_MAC) if (pluginsDir.dirName() == "MacOS") { pluginsDir.cdUp(); pluginsDir.cdUp(); pluginsDir.cdUp(); } #endif pluginsDir.cd("plugins"); foreach (QString fileName, pluginsDir.entryList(QDir::Files)) { QPluginLoader pluginLoader(pluginsDir.absoluteFilePath(fileName)); QObject *plugin = pluginLoader.instance(); qDebug() << "--->>>Lynn<<<---" << __FUNCTION__ << pluginLoader.errorString(); if (plugin) { m_pInterface = qobject_cast<CalInterface *>(plugin); if (m_pInterface) return true; } } return false; }