Connection problem with menubar using Designer

[calhal]

You've declared aboutAction inside your UI with QtDesigner, so you should refere to it like this:

connect( &ui.aboutAction, SIGNAL(triggered()), this, SLOT(about()) );

connect( &ui.aboutAction, SIGNAL(triggered()), this, SLOT(about()) );

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If you run your code from console I guess you'll get message that object aboutAction doesn't exist.