Qt4：使全屏 window 无法绕过（锁定屏幕）？

Question

My application is an OS lock screen (like GDM's lock screen or KDE's), so I'm trying to make it function like one.

I am trying to make my application's window hover above all other windows and disable/intercept all keyboard shortcuts ( ALT-TAB , CTRL-ALT-D , etc.) that would cause it disappear.

Is there any way to do this? I'm 100% sure there is, as lock screens with GUIs exist, but I just can't find the place to look...

Answer 1

I don't know how to do it with Qt, but what you are looking for is called grabbing . You can grab the pointer input device as well as the keyboard .

Edit: Looking in to the Qt4 docs, have you tried to use QWidget::grabMouse ? It looks like this function does exactly what you want.

Answer 2

inherit Qwidget class with parameter Qt::WindowStaysOnTopHint see below

myclass::myclass(QWidget *parent) : QWidget(parent,Qt::WindowStaysOnTopHint)

Answer 3

I don't know if this is the best solution, but you can try an event handler using QObject::installEventFilter() .

If you are using Windows, you can install an event filter that handles messages where event->type() == QEvent::WinEventAct .

I don't really know much about other OSs, but Qt probably has something for that too.