我如何调用dataChanged

Question

以下是我添加的行类.它是由代码而不是表调用的,我希望它在添加新行时正确调用dataChanged,虽然这不起作用,但表没有做任何事情.我究竟做错了什么？

void MyModel::add(const Person& p)
{
    people.push_back(p);

    QModelIndex top = createIndex(people.count() - 1, 0, 0);
    QModelIndex bottom = createIndex(people.count() - 1, 3, 0);

    emit dataChanged(top, bottom); // emit layoutChanged() if headers changed
}

Answer 1

dataChanged仅适用于现有数据,您需要调用beginInsertRows()/endInsertRows()

void MyModel::add(const Person& p)
{
    beginInsertRows(QModelIndex(), people.count(), people.count());
    people.push_back(p);
    endInsertRows();

    QModelIndex top = createIndex(people.count() - 1, 0, 0);
    QModelIndex bottom = createIndex(people.count() - 1, 3, 0);

    emit dataChanged(top, bottom); // emit layoutChanged() if headers changed
}

这应该工作.可能你甚至不需要emit dataChanged