code: def next_event(self, delete=False):
          if delete:
              msg = "Delete this event? This cannot be undone."
              msgbox = QMessageBox(QMessageBox.Question, 'Delete event', msg)
              msgbox.setStandardButtons(QMessageBox.Yes | QMessageBox.No)
              msgbox.setDefaultButton(QMessageBox.Yes)
              response = msgbox.exec_()
              if response == QMessageBox.No:
                  return
          event_sel = self.event_sel
          if event_sel is None:
              return
          notes = self.parent.notes
          if not self.current_event_row:
              row = notes.find_row(event_sel.marker.x(),
                              event_sel.marker.x() + event_sel.marker.width())
          else:
              row = self.current_event_row
          same_type = self.action['next_of_same_type'].isChecked()
          if same_type:
              target = notes.idx_annot_list.item(row, 2).text()
          if delete:            
              notes.delete_row()
              msg = 'Deleted event from {} to {}.'.format(event_sel.marker.x(), 
                              event_sel.marker.x() + event_sel.marker.width())
              self.parent.statusBar().showMessage(msg)
              row -= 1
          if row + 1 == notes.idx_annot_list.rowCount():
              return
          if not same_type:
              next_row = row + 1
          else:
              next_row = None
              types = notes.idx_annot_list.property('name')[row + 1:]
              for i, ty in enumerate(types):
                  if ty == target:
                      next_row = row + 1 + i
                      break
              if next_row is None:
                  return                
          self.current_event_row = next_row
          notes.go_to_marker(next_row, 0, 'annot')
          notes.idx_annot_list.setCurrentCell(next_row, 0)