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callback parameters when using gtk_builder

Iam using Glade for GUI building and Gtkbuilder for connecting signals.

As a newbie i got confused with the parameter type of 'data' in the code

Code:

gtk_builder_connect_signals( builder, data);

'data' is a struct where i have my UIdata stored eg data->button1 ,data->label1........data->label4

Code:

/* Main data structure definition */



typedef struct _ChData ChData;

struct _ChData

{

        /* Widgets */



        GtkWidget *window1;  /* Main application window */

        GtkWidget *label1;

        GtkWidget *label2;

        GtkWidget *label3;

        GtkWidget *label4;

};



#endif /* __SUPPORT_H__ */

i have added the Gobject pointers properly with the ChData

Main window has a button and i need to update label4 upon the click of the button . as show below

Code:

G_MODULE_EXPORT gboolean

button1_clicked_cb( GtkWidget   *widget,

                                 GdkEventExpose *event,

                                 ChData         *data )

{        

        

        g_print ("DAQ started now\n");

        gtk_label_set_text (GTK_LABEL(data->label4), g_strdup_printf ("DAQ started now"));

        

        return( TRUE );

        

}

All the code compiles without error

but when i run it

g_print is working but gtk_label runs into segmentation fault!!

Can some one throw some light on passing UI data to callbacks?

Re: callback parameters when using gtk_builder

Quote:

Originally Posted by rajasekaran (Post 336761)

Iam using Glade for GUI building and Gtkbuilder for connecting signals.

As a newbie i got confused with the parameter type of 'data' in the code

Code:

gtk_builder_connect_signals( builder, data);

this should be:

Code:

gtk_builder_connect_signals( builder, (gpointer*)data);

Re: callback parameters when using gtk_builder

thanks for the reply...

i solved the bug .. it was a mistake in the button clicked callback function input arguments. there is no eventexpose parameter passed in button click callback. when i deleted the 2nd input argument things worked.