[Gimp-developer] connecting to update signal in uimanager

[Martin Nordholts]

On 07/01/2009 12:08 AM, Jordan Stinson wrote:
> static void
> toolbox_create_commands (GimpToolbox *toolbox,
>                                                GimpContext *context)
> {
>     GimpUIManager *ui_manager = GIMP_IMAGE_DOCK (toolbox)->ui_manager;
>     ...
>    g_signal_connect (G_OBJECT (ui_manager), "update", G_CALLBACK 
> (toolbox_refresh_commands),
>                 (gpointer) toolbox);
> }
>
> /*Callback function*/
> static void
> toolbox_refresh_commands (GimpUIManager *ui_manager, gpointer data)
> {
>     GimpToolbox *toolbox = GIMP_TOOLBOX (data);
>     if (toolbox)
>         gimptoolbox_refresh_commands (toolbox);
> }

Hi,

Please don't break threads by sending to just one persion, continue the 
thread on gimp-developer.

The "update" signal on GimpUIManager has a parameter, as can be seen in 
app/widgets/gimpuimanager.c:

   manager_signals[UPDATE] =
     g_signal_new ("update",
                   G_TYPE_FROM_CLASS (klass),
                   G_SIGNAL_RUN_LAST,
                   G_STRUCT_OFFSET (GimpUIManagerClass, update),
                   NULL, NULL,
                   gimp_marshal_VOID__POINTER,
                   G_TYPE_NONE, 1,
                   G_TYPE_POINTER);

where 1, G_TYPE_POINTER means the signal has one parameter of type 
pointer. It is this parameter you get in your 'data' in your callback. 
Your callback signature shall look like it does for other clients, such 
as the tool options menu:

   g_signal_connect (manager, "update",
                     G_CALLBACK (tool_options_menu_update),
                     (gpointer) ui_path);

   // ...

static void
tool_options_menu_update (GimpUIManager *manager,
                           gpointer       update_data,
                           const gchar   *ui_path)

I.e. you need to "make room" for the "update" signal parameter.

Hope this helps,

  / Martin