Qt connect no such slot when slot definitely does exist

qobject__connect_ no such slot
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But when the connect statement is executed on this one I get … QObject::connect: No such slot QtVTKApp::setWidgetsEnabled() I read something

Starting E:01_project03_C++keydebug Object::connect: No such slot MainWindow::GenerateKey() in :26 Object::connect

cats online slot QObject::connect: No such signal ClassicComicsView::doubleClicked 17:58: WARNING QObject::connect: No such slot

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