Re: gsignals and closure

[Jan-Marek Glogowski <glogow fbihome de>]

Hi

> I'm trying to add parameters to my gsignal implementation.  Is the use
> of a closure function required to handle parameters?

You need marshallers to pass parameters.

There are two possible points of failure: signal declaration, or signal
emitting.

I will just provide an example from my code - HTH to find you problem.
BTW does your program shows any g_log messages, when run from the console?

singit_marshallers.list:

INT:STRING,INT

karaoke_data.h:

struct _SingitKaraokeDataClass
{
        GObjectClass parent_class;

        gint (* render) (SingitKaraokeData *skd, const gchar *text, gint
line);
        ...
};

karaoke_data.c:

enum {
        RENDER,
        ...,
        LAST_SIGNAL
};

static gint skd_signals[LAST_SIGNAL];

static void singit_karaoke_data_class_init
        (gpointer g_class, gpointer g_class_data)
{
        GObjectClass *object_class = G_OBJECT_CLASS(g_class);
        SingitKaraokeDataClass *klass =
SINGIT_KARAOKE_DATA_CLASS(g_class);

skd_signals[RENDER] =
                g_signal_new("render",
                        G_OBJECT_CLASS_TYPE (object_class),
                        G_SIGNAL_RUN_LAST,
                        G_STRUCT_OFFSET (SingitKaraokeDataClass, render),
                        NULL, NULL,
                        g_cclosure_user_marshal_INT__STRING_INT,
                        G_TYPE_INT, 2,
                        G_TYPE_POINTER,
                        G_TYPE_INT);

klass->render = NULL;

...

const gchar *line = "my line";
gint pixel_len = -1;
g_signal_emit( skd_object, skd_signals[RENDER],
                0, NULL, line, &pixel_len );

...

Any other program file:

gint skd_render(SingitKaraokeData *skd, const gchar *text,
        gint line, gpointer data)
{
        return line;
}

HTH

Jan-Marek