QWidgetDock + floatable

Hey!
How can I catch action when I click on floatable button in QDockWidget?

For example:
How catch (change) action when I click mark button on picture below
Attachment 3499

Sorry for my english:p
Thanks:)

The documentation is your friend. Use them:

Quote:

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void QDockWidget::topLevelChanged ( bool topLevel ) [signal]

This signal is emitted when the floating property changes. The topLevel parameter is true if the dock widget is now floating; otherwise it is false.

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I know this signal, but I want use this button for my action,and I dont know how. what I must to do? Maybe I must override function, but which?
Thanks.