+Finally, there is another additional complication (which, in fact, simplifies
+life of wxWindows programmers significantly): when propagating the command
+events upwards to the parent window, the event propagation stops when it
+reaches the parent dialog, if any. This means that you don't risk to get
+unexpected events from the dialog controls (which might be left unprocessed by
+the dialog itself because it doesn't care about them) when a modal dialog is
+popped up. The events do propagate beyond the frames, however. The rationale
+for this choice is that there are only a few frames in a typical application
+and their parent-child relation are well understood by the programmer while it
+may be very difficult, if not impossible, to track down all the dialogs which
+may be popped up in a complex program (remember that some are created
+automatically by wxWindows). If you need to specify a different behaviour for
+some reason, you can use
+\helpref{SetExtraStyle(wxWS\_EX\_BLOCK\_EVENTS)}{wxwindowsetextrastyle}
+explicitly to prevent the events from being propagated beyond the given window
+or unset this flag for the dialogs which have it on by default.
+