How to restore an OS X application window after hiding with Cmd-H

If you have hidden an OS X Application with Cmd-H (aka Apple-H = ⌘-H) the hidden window cannot be shown again by calling slot show(). In this case you must call

If you have installed a system tray icon with QSystemTrayIcon [doc.qt.nokia.com] you can add a menu entry and connect the QAction’s [doc.qt.nokia.com] triggered() signal with the respecitve slots.