Re: Signal blocking

[Chad Robinson <crj lucubration com>]

Arne Caspari wrote:
> Hi!
>
> I want to block the emission of the "value_changed" signal when I call
> gtk_range_set_value( ... )
>
> My code so far is roughly:
>
> /********************************************************************/
> handler_id = g_signal_connect( GTK_RANGE( widget ) , "value_changed",
> cb_func, data );
> .
> .
> .
> g_signal_handler_block( widget, handler_id );
> gtk_range_set_value( GTK_RANGE( widget ), .... );
> g_signal_handler_unblock( widget, handler_id );
> g_signal_stop_emission_by_name( widget, "value_changed" );
> /********************************************************************/
>
> But the value_changed callback is called anyways. How do I temporarly
> disable the signal handler?

I'm sure there's a GTK solution, but is there any reason you don't just:

    static int ignore_signals = 0;

    cb_func(...)
    {
        if (ignore_signals) return;
        ...
    }

    handler_id = g_signal_connect( GTK_RANGE( widget ) , "value_changed",
                                   cb_func, data );
    .
    .
    .
    ignore_signals++;
    gtk_range_set_value( GTK_RANGE( widget ), .... );
    ignore_signals--;

It requires a global (unless you're passing state data in via a struct via the 
data parameter to cb_func, and can add an element to the struct), but it's not 
really any uglier and eliminates the mucking about with signals.

Regards,
Chad