Re: Signals in threads

[Bob Caryl <bob fis-cal com>]

Hey Mike:

First, you need to declare a Gtk::Dispatcher object in your GUI class.  
It will be the conduit from your worker threads to your GUI (and usually 
primary) thread.  Next, in your GUI class you declare a function to 
handle the data coming from your worker thread that you will use to 
update your GUI, and you use it as a callback slot to connect to your 
Gtk::Dispatcher:

Gtk::Dispatcher my_dispatcher;
my_dispatcher.connect(sigc::mem_fun(*myclass,&MyClass::my_callback_slot));

Then, in the worker thread, you just call the dispatcher as a function:

my_dispatcher();

whenever you wish to update your GUI. 

In my case, I had also declared in my GUI class a 
std::vector<Glib::ustring> object to which my worker thread pushed back 
string data that I wanted to add to a Gtk::TextBuffer displayed in a 
Gtk::TextView in my GUI class.  My callback slot would pop the 
Glib::ustrings off this vector one at a time and add them to the 
Gtk::TextBuffer whenever it was called by the dispatcher.  Therefore, my 
worker thread would push back strings to this vector object just prior 
to calling the dispatcher.

I hope this helps.

Bob

/*Bob Caryl*
Fiscal Systems,Inc.
256.772.8920 Ext. 108
http://www.fis-cal.com <http://www.fis-cal.com/>/

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Mike Polan wrote:
> Hi,
> I need to emit certain signals inside a running Glib::Thread in order 
> to relay some information to the rest of my app. However, from what I 
> know, I don't believe that it is really safe to emit such signals that 
> are connected to a Gtk::Window, which in turn will call some GUI 
> functions, directly from inside threads. Someone mentioned something 
> about Glib::Dispatcher to me, but I'm not quite sure if that's what's 
> needed to accomplish my task. In any case, how would I go about doing 
> something like this?
>
> Thanks in advance.
> ------------------------------------------------------------------------
>
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