How delete Qt Layout manager from another method?

[hobbyist]

What exactly do you want to do?

Do you want to replace the box layout with a grid layout?

You can only use setLayout once, but there is also the option of adding another using addLayout.

QBoxLayout.addLayout(QLayout *layout, int stretch = 0)

https://doc.qt.io/qt-5/qboxlayout.html#addLayout

I have placed a Button to the main window and when I press it I want to open new smaller auxiliary window to display some information... (The new auxiliary smaller window has GridLAyout). Can I achieve this?