qtablewidget的信号void itemChanged(QTableWidgetItem * item)可以知道。当combobox的内容变化了后,qtablewdiget就会发射这个信号,从传过来的参数中可以获取对应的某行某列item->column(); item->row();
void QTableWidget::itemChanged(QTableWidgetItem * item)
This signal is emitted whenever the data of item has changed.