def METHOD_NAME(self, event: "QKeyEvent") -> None:
    if event.key() == Qt.Key_X:
        # xrefs
        if self._model is None:
            return
        selected_rows = list(self.selectionModel().selectedRows())
        if len(selected_rows) == 1:
            model_index = self._proxy.mapToSource(selected_rows[0])
            selected_index = model_index.row()
            if 0 <= selected_index < len(self._model.values):
                selected_item: MemoryData = self._model.values[selected_index]
                dialog = XRefDialog(
                    addr=selected_item.addr,
                    dst_addr=selected_item.addr,
                    xrefs_manager=self.xrefs,
                    instance=self._instance,
                    parent=self,
                )
                dialog.exec_()
        return
    return super().METHOD_NAME(event)