QFileOpenEvent Class

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>CFBundleDocumentTypes</key>
    <array>
        <dict>
            <key>CFBundleTypeExtensions</key>
            <array>
                <string>png</string>
            </array>
            <key>CFBundleTypeRole</key>
            <string>Viewer</string>
        </dict>
    </array>
</dict>
</plist>

#include <QApplication>
#include <QDebug>
#include <QFileOpenEvent>
#include <QPushButton>

class MyApplication : public QApplication
{
public:
    MyApplication(int &argc, char **argv)
        : QApplication(argc, argv)
    {
    }

    bool event(QEvent *event) override
    {
        if (event->type() == QEvent::FileOpen) {
            QFileOpenEvent *openEvent = static_cast<QFileOpenEvent *>(event);
            const QUrl url = openEvent->url();
            if (url.isLocalFile()) {
                QFile localFile(url.toLocalFile());
                // read from local file
            } else if (url.isValid()) {
                // process according to the URL's schema
            } else {
                // parse openEvent->file()
            }
        }

        return QApplication::event(event);
    }
};