QT监听全局事件

application.h

#ifndef APPLICATION_H
#define APPLICATION_H

#include <QApplication>
#include <QMouseEvent>
#include <QTouchEvent>
#include <QDebug>

class Application : public QApplication
{
    Q_OBJECT

public:
    Application(int &argc, char **argv) : QApplication(argc, argv) {}
    bool notify(QObject *obj, QEvent *e) override
    {
        switch (e->type()) {

        case QEvent::TouchBegin:
        case QEvent::TouchEnd:
        case QEvent::TouchUpdate:
        case QEvent::TouchCancel:
        {
            QTouchEvent *touchEvent = reinterpret_cast<QTouchEvent *>(e);

            QList<QTouchEvent::TouchPoint> touchPoints = touchEvent->touchPoints();
            foreach(QTouchEvent::TouchPoint t, touchPoints) {
                //            qDebug() << "###TP" << t;
            }
            break;
        }

        default:
            break;
        }

        if (e->type() == QEvent::MouseButtonPress || e->type() == QEvent::TouchBegin) {
            emit userOperated();
        }

        return QApplication::notify(obj, e);
    }

    template <typename ... Args>
    QMetaObject::Connection callOnUserOperated(Args && ...args)
    {
        return QObject::connect(this, &Application::userOperated, std::forward<Args>(args)... );
    }

Q_SIGNALS:
    void userOperated();
};

#endif // APPLICATION_H

main.cpp

#include "application.h"

int main(int argc, char *argv[])
{
    Application a(argc, argv);

    return a.exec();
}