PySide exception/object lifetime MVCE

import logging
import sys
import weakref

from PySide import QtGui


class InnerPresenter:
    def __init__(self, view):
        self._view = weakref.ref(view)
        self.logger = logging.getLogger('InnerPresenter')
        self.logger.debug('Initializing InnerPresenter (id:%s)' % id(self))

    def __del__(self):
        self.logger.debug('Deleting InnerPresenter (id:%s)' % id(self))

    @property
    def view(self):
        return self._view()

    def on_alert(self):
        self.view.show_alert()

    def on_raise_exception(self):
        raise Exception('From InnerPresenter (id:%s)' % id(self))


class OuterView(QtGui.QMainWindow):
    def __init__(self, *args, **kwargs):
        super(OuterView, self).__init__(*args, **kwargs)
        self.logger = logging.getLogger('OuterView')
        # Menus
        menu_bar = self.menuBar()
        test_menu = menu_bar.addMenu('&Test')
        self.open_action = QtGui.QAction('&Open inner', self, triggered=self.on_open, enabled=True)
        test_menu.addAction(self.open_action)
        self.close_action = QtGui.QAction('&Close inner', self, triggered=self.on_close, enabled=False)
        test_menu.addAction(self.close_action)

    def closeEvent(self, event, *args, **kwargs):
        self.logger.debug('Exiting application')
        event.accept()

    def on_open(self):
        self.setCentralWidget(InnerView(self))
        self.open_action.setEnabled(False)
        self.close_action.setEnabled(True)

    def on_close(self):
        self.setCentralWidget(None)
        self.open_action.setEnabled(True)
        self.close_action.setEnabled(False)


class InnerView(QtGui.QWidget):
    def __init__(self, *args, **kwargs):
        super(InnerView, self).__init__(*args, **kwargs)
        self.logger = logging.getLogger('InnerView')
        self.logger.debug('Initializing InnerView (id:%s)' % id(self))
        self.presenter = InnerPresenter(self)
        # Layout
        layout = QtGui.QHBoxLayout(self)
        alert_button = QtGui.QPushButton('Alert!', self, clicked=self.presenter.on_alert)
        layout.addWidget(alert_button)
        raise_button = QtGui.QPushButton('Raise exception!', self, clicked=self.presenter.on_raise_exception)
        layout.addWidget(raise_button)
        self.setLayout(layout)

    def __del__(self):
        self.logger.debug('Deleting InnerView (id:%s)' % id(self))

    def show_alert(self):
        QtGui.QMessageBox(text='Here is an alert').exec_()


if __name__ == '__main__':
    logging.basicConfig(level=logging.DEBUG)
    app = QtGui.QApplication(sys.argv)
    view = OuterView()
    view.show()
    sys.exit(app.exec_())