Qt，C++绘制两个对象之间的连接线

#include <QtWidgets>

class MyWidget : public QWidget {
public:
    MyWidget(QWidget *parent = nullptr) : QWidget(parent) {}

protected:
    void paintEvent(QPaintEvent *event) override {
        QPainter painter(this);
        painter.setRenderHint(QPainter::Antialiasing, true);
        
        // 绘制连接线
        QPoint start(50, 50);
        QPoint end(200, 200);
        painter.drawLine(start, end);
    }
};

int main(int argc, char *argv[]) {
    QApplication app(argc, argv);
    
    MyWidget widget;
    widget.show();
    
    return app.exec();
}