'Convenience method that returns the currently visible view'

def current_view(self):

    idx = self.stack.currentIndex()
    if (idx == 0):
        return self.library_view
    if (idx == 1):
        return self.memory_view
    if (idx == 2):
        return self.card_a_view
    if (idx == 3):
        return self.card_b_view
