From: Stefano Crocco <stefano.crocco@...>
Date: 2012-08-31T20:10:13+09:00
Subject: Re: Qt signals driving me crazy

On Friday 31 August 2012 Damjan Rems wrote
> Stefano Crocco wrote in post #1074007:
> > On Friday 31 August 2012 Damjan Rems wrote
> > 
> >> by
> >> TheR
> > 
> > The correct signature for the signal is
> > 
> > 'itemActivated( QTreeWidgetItem*, int )'
> > 
> > while you used
> > 
> > 'itemActivated(TreeWidgetItem*, int )'
> > 
> > without the leading Q. You have the same problem in a couple of other
> > places.
> > Generally speaking, when you have problems with a signal-slot
> > connection, one
> > of the first things to do is to look at the output on standard error and
> > see
> > if you see a warning saying 'not such a signal' or 'not such a slot'
> > (this
> > warning is shown even if you're running ruby with warnings turned off,
> > since
> > it is generated from the Qt library on the C++ side. Unfortunately, it
> > doesn't
> > tell you where the wrong signal or slot name is).
> > 
> > I hope this helps
> > 
> > Stefano
> 
> Thanks for your answer, I have already tried that too.

Do you mean that after replacing TreeWidgetItem with QTreeWidgetItem your 
nitem_clicked slot still doesn't get called? If so, that's weird, since I 
tried it and it works for me.

> 
> I oversleep problem a little, looked into source code and found
> metaObject().signalNames method. The catch is that if I create
> TreeWidget like:
> 
> t = Qt::TreeWidget.new
> p t.metaObject().signalNames
> 
> I get nice output of all available signals, but if I write
> 
> p self.metaObject().signalNames
> 
> inside my defined TreeView class i get []. Where is the catch?
> 
> 
> by
> TheR

It may be a bug in qtruby, but I'm not sure. You can ask on the QtRuby mailing 
list (subscribing at https://mail.kde.org/mailman/listinfo/kde-bindings). If 
you don't, I'll do that one of the next days, as soon as I have a bit of free 
time. However, I've noticed that if I define a new signal in the custom class, 
metaObject#signalNames returns it, but it still doesn't contain signals from 
the base class.

Stefano