How to pass a Qwidget to a function into a children class ?

[ChrisW67]

1.- How I must to pass the label or Qtextedit to the function ?
Using pointers ? Can anyone give some easy code ?

Pass the widgets by pointer. You cannot pass them by value, even if that made sense, because they do not have the requisite copy constructor.

class MyClass {
...
private:
  QWidget *aWidget;
};
 
MyClass::record(QWidget *widget)
{
  aWidget = widget;
}

class MyClass {
...
private:
  QWidget *aWidget;
};

MyClass::record(QWidget *widget)
{
  aWidget = widget;
}

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2.- How can I identify what kind of Qwidget is 'A_widget_to_remember'

QObject qobject_cast to the relevant type and check the returned pointer.