QComboBox с QCheckBox

Извините, само заработало. Магия.

Не подскажите, как узнать checkState () этих CheakBox:

    ui->SearchCheakComboBox->addCheckItem("text0", 0, Qt::Unchecked);

    ui->SearchCheakComboBox->addCheckItem("text1", 1, Qt::Unchecked);

    ui->SearchCheakComboBox->addCheckItem("text2", 2, Qt::Unchecked);

    ui->SearchCheakComboBox->addCheckItem("text3", 3, Qt::Unchecked);

вот решение

 // grab the model
  QStandardItemModel* model = qobject_cast<QStandardItemModel*> ( ui->combobox->model() );
  if (!model) { // check is important or u can/might crash 
    qDebug() << "not QStandardItemModel !";
    return;
  }
-----
  // check all if checked
  for (int row = 0; row < model->rowCount(); ++row) {
    if (model->item(row)->checkState() == (Qt::CheckState::Checked)) {
      qDebug() << "checked";
    }
  }
  // set all to checked
  for (int row = 0; row < model->rowCount(); ++row) {
    model->item(row)->setCheckState(Qt::CheckState::Checked);
  }