QFile as an argument of a function?

[Stanfillirenfro]

Maybe I was not clear.
In my code, at the level of first class.cpp line 11, we have:

QStringList Heritage::operation1(QString fileName)

QStringList Heritage::operation1(QString fileName)

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On the line 14, we have:

QFile file1(m_openFile->text());

QFile file1(m_openFile->text());

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m_openFile->text() replaces what you called in your code fileName, and what I've added here too. But the variable "fileName" is not used. It was my problem.
To answer to your qestion, according to me, ChildWindow shows the path to the file to be opned to Heritage with the expression: m_openFile->text().
Could you please clarify this situation? I would be grateful to you.