Delivery app widgets

It would be nice to match the signal syntax from the QFileDialog so that this is more of a drop in replacement.
Where there is a match, could we use signals from this list:
http://qt-project.org/doc/qt-4.8/qfiledialog.html#signals

Also, is a cancelled signal needed over the QDialog's finished/rejected signals?
http://qt-project.org/doc/qt-4.8/qdialog.html#signals

Commends describing when the signals are emitted and what the arguments are should also be there.