Accessing QTabWidget's widget

Accessing QTabWidget's widget

I have a QTabWidget with 2 tabs and I promoted each to 2 custom widgets.
Those widgets have functions "typeName()" and "baseName()", but I cannot
access those functions with "QTabwidget->currentWidget()".
std::string type =
ui->tabWidget->currentWidget()->typeName().toUtf8().constData();
std::string base =
ui->tabWidget->currentWidget()->baseName().toUtf8().constData();
This throws me an error "it has no member named ..."
What am I doing wrong?