QTableView row remove - c++

Question

I created a table view like this:
I have a create button to create new rows and as you can see I defined a button for each row to delete that row by this code:
int i = 0;
QPushButton *viewButton;
QStandardItemModel *model;
void MainWindow::on_pushButton_clicked()
{
model->appendRow(new QStandardItem(QString("")));
viewButton = new QPushButton();
viewButton->setText("Delete " + QString::number(i));
ui->tableView->setIndexWidget(model->index(i , 7), viewButton);
connect(viewButton , SIGNAL(clicked()) , this , SLOT(button_clicked()));
i++;
}
and I created a slot for each button clicked for remove a row:
void MainWindow::button_clicked()
{
// by this line I can get the sender of signal
QPushButton *pb = qobject_cast<QPushButton *>(QObject::sender());
}
as you can see I know witch button sends signal and now I need to delete that row.
here is my question:
how can I get the row of sender button in table view to remove that row?
I searched everywhere and I didn’t realise how to get the row and column of an item.

Answer 1

On workaround is to use QObject::setObjectName and set some names to the buttons you add :
viewButton.setObjectName(QString("%1").arg(i));
And in button_clicked slot you can retrieve the row number using the object name :
void MainWindow::button_clicked()
{
// by this line I can get the sender of signal
QPushButton *pb = qobject_cast<QPushButton *>(QObject::sender());
int row = pb->objectName().toInt();
}
Note that you should update object names after a row is removed.
Another way is to use the QSignalMapper class which collects a set of parameterless signals, and re-emits them with integer, string or widget parameters corresponding to the object that sent the signal. So you can have one like:
QSignalMapper * mapper = new QSignalMapper(this);
QObject::connect(mapper,SIGNAL(mapped(int)),this,SLOT(button_clicked(int)));
When adding your buttons in each row of table view, you can connect the clicked() signal of the button to the map() slot of QSignalMapper and add a mapping using setMapping so that when clicked() is signaled from a button, the signal mapped(int) is emitted:
viewButton = new QPushButton();
viewButton->setText("Delete " + QString::number(i));
ui->tableView->setIndexWidget(model->index(i , 7), viewButton);
QObject::connect(viewButton, SIGNAL(clicked()),mapper,SLOT(map()));
mapper->setMapping(but, i);
This way whenever you click a button in a row, the mapped(int) signal of the mapper is emitted containing the row number and consequently button_clicked is called with a parameter containing the row number.
Also here you should update the mappings in button_clicked slot since the row is removed when you click an item.