Need a little guidance with signals

[Mark Richardson <markmapo yahoo com>]

Hi All,

I've been having a little trouble with signals.  I'm using gladeXML to change views inside of my application.  In the .glade file that I'm opening, there are some custom widgets.  When I create a custom widget, I keep a pointer to it for some internal purposes.  But I want the pointer to be set to null when the widget is destroyed (or a new .glade file is loaded). So I'm using signals, but I end up with some strange behavior...

 

// globals

GtkWidget *pointerToCustomWidget=NULL;

guint signalHandlerId=0;

 

// this function called when gladeXML creates the widget

GtkWidget *createCustomWidget(gchar *widget_name, gchar *string1, gchar *string2, gint int1, gint int2)

{

  GtkWidget *myCustomWidget=createMyCustomWidget(); // my code to create the widget

  pointerToCustomWidget=myCustomWidget;

  signalHandlerId=g_signal_connect(gpointer(myCustomWidget), "destroy", G_CALLBACK(gtk_widget_destroyed), &pointerToCustomWidget);

  // also tried this signalHandlerId=gtk_signal_connect(GTK_OBJECT(myCustomWidget), "destroy", GTK_SIGNAL_FUNC(gtk_widget_destroyed), &pointerToCustomWidget);

}

 

// At some pointer user clicks a button and I do the following

if (pointerToCustomWidget!=NULL && signalHandlerId>0)

{

  GtkWidget *tempWidgetPointer=pointerToCustomWidget;

  guint tempSignalHandlerId;

  tempSignalHandlerId=g_signal_connect(gpointer(tempWidgetPointer), "destroy", G_CALLBACK(gtk_widget_destroyed), &tempWidgetPointer);

 

  // do some other stuff

  g_signal_handler_disconnect(gpointer(tempWidgetPointer), tempSignalHandlerId);

  tempWidgetPointer=NULL;

}

 

I get some errors like this..

Gtk-CRITICAL **: gtk_signal_compat_matched: assertion 'GTK_IS_OBJECT(object)' failed

 

My actual code has a more assignments like the above, so sometimes I end up having 3 or 4 pointers and handlers using the same techniques.

 

If I remove the following line of code...

assignment tempWidgetPointer=NULL;

I get errors like this...

Gtk-WARNING **: unable to find signal handler for object(CustomWidget:0x8b5e4b0) with func(0x81a1618) and data (0xbffeca30)

 

I thought I understood how signals work, but I now I know that I don't have a clue.

 

Thanks for any help,

Mark

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