获取从 QTableWidget 中的单元格小部件发出的信号发送器的行索引

Question

我有一个包含 3 列的 QTableWidget。前两列存储 QDateTimeEdit 项。第三个存储一个 QSpinBox，它应该列出该行中两个 QDateTimeEdit 值之间的持续时间。

如何连接 QDateTimeEdit 的信号以自动更新 QSpinBox 中的持续时间以防某个日期时间更改？

...
for (int i_row = 0; i_row < 100; ++i_row){
    QTableWidget *t = ui->tableWidget;
    QDateTimeEdit *start = new QDateTimeEdit();
    QDateTimeEdit *end   = new QDateTimeEdit();
    t->setCellWidget(i_row,0,start);
    t->setCellWidget(i_row,1,end);

    QSpinBox *sp = new QSpinBox();
    sp->setReadOnly(true);
    t->setCellWidget(i_row,2,sp);

    connect(start, SIGNAL(dateTimeChanged(const QDateTime &)), this, SLOT(adjustDuration()));
    connect(end,   SIGNAL(dateTimeChanged(const QDateTime &)), this, SLOT(adjustDuration()));
}

与插槽：

void mainWindow::adjustDuration()
{
    QDateTimeEdit *s = qobject_cast<QDateTimeEdit *>(sender());
    // How do I get row number of the sender within QTableWidget in order to be able to access proper 2nd QDateTimeEdit and QSpinBox? 
    // Simplified speaking: I would like to get the value i_row from the code before
}

我想可以通过使用 ->parent() 函数来实现吗？

Answer 1

假设您使用的是 Qt5，那么您可以使用 lambda。所以像（未经测试）...

for (int i_row = 0; i_row < 100; ++i_row){
    QTableWidget *t = ui->tableWidget;
    QDateTimeEdit *start = new QDateTimeEdit();
    QDateTimeEdit *end   = new QDateTimeEdit();
    t->setCellWidget(i_row, 0, start);
    t->setCellWidget(i_row, 1, end);

    QSpinBox *sp = new QSpinBox();
    sp->setReadOnly(true);
    t->setCellWidget(i_row, 2, sp);

    auto eval = [start, end, sp]()
                {

                    /*
                     * Here you have 'start', 'end' and 'sp'.  Use them
                     * in whatever way you see fit.
                     */
                };

    connect(start, &QDateTimeEdit::dateTimeChanged, eval);
    connect(end,   &QDateTimeEdit::dateTimeChanged, eval);
}

获取从 QTableWidget 中的单元格小部件发出的信号发送器的行索引

get row index of signal sender emitted from cell widget in QTableWidget

c++

qt

signals-slots