How to detect when a QDockWidget is moved out of a QMainWindow?

问题

There is a signal which allows the user to know where a QDockWidget has been moved inside a QMainWindow :

void dockLocationChanged(Qt::DockWidgetArea area)

The problem is that this signal is not fired when a QDockWidget is moved out of the QMainWindow (either by dragging or by double-clicking the dockwidget's title bar).

Is there a way to detect that event, without reimplementing moveEvent()?

回答1:

There is a floating property exactly for that purpose, and a topLevelChanged signal.

来源：https://stackoverflow.com/questions/38221768/how-to-detect-when-a-qdockwidget-is-moved-out-of-a-qmainwindow