Implementing notification dialogs that don't steal focus from full-screen apps?

Question

I want to implement a notification window by subclassing QDialog. It should be on top of other windows, but I don't want it to steal focus from other windows for obvious reasons. I'm also concerned that it would interfere with full-screen applications like videos and games.

How do I go about implementing this? Are there any common programming and UX practices I might want to know about?

Answer 1

It appears quite an old topic. However, I did not see anyone posting a proper answer that just works, so I am posting my solution to the same problem I have been facing recently.

First of all, if you want your dialog not to steal focus from other dialogs or input fields, you should set the following property: Qt::WA_ShowWithoutActivating. Using this property, window (dialog is also a window) will be shown without being activated. Then, probably you will want to customize your dialog to your needs, and you will want this dialog to be shown on top. So, the following Window flags can be set in order to achieve such a result in a cross-platform manner: Qt::FramelessWindowHint | Qt::NoDropShadowWindowHint | Qt::X11BypassWindowManagerHint | Qt::Tool | Qt::WindowStaysOnTopHint | Qt::WindowTransparentForInput | Qt::WindowDoesNotAcceptFocus.

The code below is one of the examples to achieve a dialog that is modeless, and does not steal focus from anyone (assuming dialog is a variable pointing to the valid instance of QDialog):

dialog->setAttribute(Qt::WA_ShowWithoutActivating, true);
dialog->setWindowFlags(dialog.windowFlags() | Qt::FramelessWindowHint | Qt::NoDropShadowWindowHint | Qt::X11BypassWindowManagerHint | Qt::Tool | Qt::WindowStaysOnTopHint | Qt::WindowTransparentForInput | Qt::WindowDoesNotAcceptFocus);

Answer 2

Haven't tried it but it looks like

my_dialog->setWindowFlags(Qt::CustomizeWindowFlags | ... | Qt::WindowStaysOnTopHint);

should work, in conjunction with making it modeless.