[Qt-interest] Forcing a signal "emit" to be queued

[Thiago Macieira]

On Monday, 21 de March de 2011 12:00:03 Mandeep Sandhu wrote:
> Hi All,
> 
> Sometime back I had a requirement where I didn't want ppl using my
> class's signals to connect to them directly. Currently if you do 'emit
> mySignal()', it's upto to the class that uses this signal, to decide
> how it would like to connect to it.
> 
> For forcing a queued a connection, I thought of the following approach:
> 
> connect(this, SIGNAL(myInternalSignal(), this, SIGNAL(mySignal()),
> Qt::QueuedConnection);
> 
> Basically I'm chaining my signal and re-emitting it with the queued
> connection type (I've yet to verify this code though).
> 
> How can one verify if the slot is indeed called in a queued connection?

Well, there's no SLOT above. The above makes the signal-signal connection be 
queued. It's clear from the code.

If anything is connected to the signal mySignal(), then it will be delivered 
through standard mechanisms when mySignal itself is invoked.

In other words, when compared to myInternalSignal(), the slots are either 
queued or doubly queued.

-- 
Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org
  Senior Product Manager - Nokia, Qt Development Frameworks
      PGP/GPG: 0x6EF45358; fingerprint:
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