The problem arises from the usage of the method m_model.setStringList(). The latter always clear the previous data, hence the index always reset upon its call.
Solution:
Use m_model.setStringList() only in the constructor to init the model.
After that manually insert the row on the model and set the data for the respective row. This can be achieved with a simple modification in the slot method.
MainWindow::MainWindow(QWidget *parent)
: QMainWindow(parent)
, ui(new Ui::MainWindow)
{
ui->setupUi(this);
m_model.setStringList({"1","2"});
ui->comboBox->setModel(&model);
}
void MainWindow::on_pushButton_clicked()
{
m_model.insertRow(model.rowCount());
m_model.setData(model.index(model.rowCount()-1), "3");
}
In the example above, "3" is appended to the list model without changing the current index from the QComboBox.
